Showing posts sorted by relevance for query airborne. Sort by date Show all posts
Showing posts sorted by relevance for query airborne. Sort by date Show all posts

Wednesday, April 8, 2020

SARS-CoV-2 is an Airborne Virus?

I thought I would say something more about airborne viruses. They have been a hobby of mine for some time.  The first time I heard about how easily the current coronavirus was spreading I thought “this is an airborne virus”. But then there were the usual protests. Some scientists came out and said that coronavirus requires “droplet” precautions rather than “airborne” precautions. The common definition is that droplets are large enough settle out quickly. They may touch you directly if you are close enough but a lot of what droplets do is settle on surfaces. That leads to surface contamination and spread of the virus.  Airborne viruses can travel longer distances within smaller droplets. An even more unique characteristic is that airborne viruses are released with normal expiration. No coughing, sneezing, or shouting is necessary. Just normal breathing can release airborne respiratory viruses into the air in the smallest droplet fraction.

An easy way to conceptualize airborne viral spread is to look at the distribution of particles occurring with every breath. They can range in size from 200 µm on the large end to less than 5 µm on the lower end. Experiments can be done to show how aerosols of these particle sizes spread through a room. Naturalistic experiments can also look at how these are all spread through hospitals, airplanes, and other natural settings. By looking at those patterns and the distance involved as well as any other paths that could lead to transmission – a determination can be made about whether or not a viruses “airborne” or not.

The second issue is whether or not live infectious virus is spread by these droplets. In many cases that has been limitation in the experiments. Direct evidence of viral spread at a distance requires culture of the virus or a bioassay that shows the samples have a cytopathic (killing) effect on live cells. Indirect evidence is typically by PCR where the available nucleic acid is amplified and assayed.  In researching this topic, I found early literature that documented numerous respiratory viruses in ventilation systems of buildings. That research was possible because nobody knew how to capture and culture the virus samples until that time. The other technical issue is air sampling. Certain air sampling devices do not allow for adequate virus detection. There is a technical report recently that showed of a total of four commonly used air sampling devices only one allowed virus to be identified or cultured. These technical constraints have led to a lot of confusion about whether a particular virus is airborne or not.

A practical definition of an airborne virus is one that is exhaled during normal breathing can travel a distance in small droplets (less than 5 µm) and create infection by landing on mucosal surfaces, facial services, or the lining of the nasopharynx, oropharynx, or lungs.  In that case you don’t have to be in the presence of anyone coughing or sneezing. You don’t have to touch any contaminated surfaces. You don’t have to touch your face. You just have to breathe contaminated air. It is entirely possible that you can walk through a cloud of airborne virus and not be aware of how it got there. A common example is walking down the hallway after a crowd of people have walked through some of them carrying the virus. Once you know about airborne viruses it gives you an entirely different perspective on social distancing.  Airborne particles can easily transverse the longest dimension of typical rooms. The distance of 6 feet suggested in typical social distancing guidelines is not nearly far enough.

In a previous post I highlighted an experiment by Donald K. Milton where he designed a machine to sample flu viruses in a natural setting. Research subjects breathed normally and their expired air was sampled for influenza virus. Influenza virus was recovered from 89% of the nasopharyngeal swabs and 39% of the fine aerosol sample defined as droplets less than or equal to 5 µm and greater than 0.05 µm. There was no coughing or sneezing during the collection.. That is proof that influenza virus is airborne.

A recent experiment carried out at the University of Nebraska Medical Center (3) in their bio containment and quarantine units showed that in addition to abundant surface contamination by SARS-CoV-2 the virus was also present in hallway air samples, in areas where only aerosol deposits could reach, and personal air samplers carried by staff.  The virus was detected by PCR analysis as well as culture in some cases. The authors concluded that this was definite evidence of an airborne virus and that facilities treating patients with SARS-CoV-2 should use airborne precautions. This paper is currently undergoing peer review and is on a preprint server.

The technical aspects of aerosol fractionation and dispersion is a subject best addressed in the engineering literature. The best paper I could find on the subject (4) had a goal of studying the dispersion characteristics of exhaled droplets in a ventilated room. The engineering goals are to find out what physical parameters affect the dispersion rate and hopefully lead to better indoor environments. The experimental paradigm looked at a room that was 5 x 4 x 3 m (L x W x H) and ventilated by a downward airflow from the ceiling. Aerosols were injected into this room and the following distance and trajectory along with trajectory time was calculated for the fractional droplets. As expected droplets with larger diameters (110-115 µm) fell at a faster rate and traveled a much shorter distance than the smaller diameter fraction. Droplet dispersion was studied under a number of physical conditions including different airflow, different temperatures, different relative humidity, and the original exhaled initial velocity.

The 0.1, 1.0, and 10 µm droplets covered horizontal distance of 5 m or the entire length of the room. Droplets in the range of 50 to 200 µm cover distances ranging from 0.5 to 4 m.  This study has numerous excellent graphs about varying conditions and how droplets in different fractions are dispersed. The reader is referred to the original reference to review all those conditions. The bottom line for me was it is clear that airborne droplets in the 0.1 to 10 µm range are commonly seen in exhaled air and easily covered distance in this experiment of 5 m or (for Americans) 16.4 feet. That is well beyond social distancing recommendations it explains why this virus continues to spread. Within the past week I have seen clips of New Yorkers in congested subway cars.  Any asymptomatic SARS-CoV-2 carriers in those cars are expelling virus into the air just by tidal volume breathing.  Coughing and sneezing is not required. It would be very good if you covered your cough or sneeze but when your mouth is not covered and you are a symptomatic or asymptomatic carrier you are exhaling viral particles.

The relevance of this virus being airborne cannot be underestimated. It is a substantial part of the reason behind social distancing and stay-at-home orders. It is the reason for the new recommendation to wear masks in public and the various explanations being given for those masks. The absolute best approach is to not have any close social contact until this pandemic is over. I am very concerned about my colleagues and fellow healthcare workers who have inadequate personal protective equipment (PPE). The expectation is that they will continue to take care of the very ill patients with COVID-19. Every effort must be made to make sure they have adequate protection. 

In my particular specialty, all psychiatrists should have access to electronic interviewing at this point. As I pointed out in my earlier posts, I am used to talking people for 30 to 60 minutes at time. Some of those evaluations are 90 minutes in duration. During that time the patient may be coughing or sneezing but for the most part they are breathing and engaged in normal interview conversation. My office is smaller than the room described in the droplet dispersion experiment. By the end of one interview, the smallest fraction of exhaled droplets is dispersed throughout the room. Any viral particles in that fraction can lead to infection.

All health care workers in these environments need immediate protection by the implementation of airborne precautions. I am hopeful that as more people become aware of the airborne route of transmission that it will lead to more caution on the part of the public and the social distancing and staying at home and away from this kind of transmission will make more sense. In the future we need to design indoor environments that can minimize this type of transmission. There is too little innovation in the role of the physical environment in airborne transmission of infectious illness.

I hope the added cost will be looked at in terms of the total cost of illnesses caused by respiratory viruses every year with the recognition that they can still cause devastating pandemics.

George Dawson, MD, DFAPA


1: Lei H, Li Y, Xiao S, Lin CH, Norris SL, Wei D, Hu Z, Ji S. Routes of transmission of influenza A H1N1, SARS CoV, and norovirus in air cabin: Comparative analyses. Indoor Air. 2018 May;28(3):394-403. doi: 10.1111/ina.12445. Epub 2018 Jan 6. PubMed PMID: 29244221. 

2: Yu IT, Li Y, Wong TW, Tam W, Chan AT, Lee JH, Leung DY, Ho T. Evidence of airborne transmission of the severe acute respiratory syndrome virus. N Engl J Med. 2004 Apr 22;350(17):1731-9. PubMed PMID: 15102999.

3: Santarpia et al. (2020) Transmission potential of SARS-CoV-2 in viral shedding observed at the University of Nebraska Medical Center. Retrieved from

4: Chen C, Zhao B. Some questions on dispersion of human exhaled droplets in ventilation room: answers from numerical investigation. Indoor Air. 2010 Apr;20(2):95-111. doi: 10.1111/j.1600-0668.2009.00626.x. Epub 2009 Sep 24. PubMed PMID: 20002792.

5: Li, Y., Huang, X., Yu, I.T.S., Wong, T.W. and Qian, H. (2005), Role of air distribution in SARS transmission during the largest nosocomial outbreak in Hong Kong. Indoor Air, 15: 83-95. doi:10.1111/j.1600-0668.2004.00317.x

6: Carl Heneghan, Jon Brassey, Tom Jefferson. SARS-CoV-2 viral load and the severity of COVID-19.  March 26, 2020.  Link

7:  National Research Council 2020. Rapid Expert Consultation on the Possibility of Bioaerosol Spread of SARS-CoV-2 for the COVID-19 Pandemic (April 1, 2020). Washington, DC: The National Academies Press.

"While the current SARS-CoV-2 specific research is limited, the results of available studies are consistent with aerosolization of virus from normal breathing."

8: Pan M, Bonny TS, Loeb J, Jiang X, Lednicky JA, Eiguren-Fernandez A, Hering S, Fan ZH, Wu CY. Collection of Viable Aerosolized Influenza Virus and Other Respiratory Viruses in a Student Health Care Center through Water-Based Condensation Growth. mSphere. 2017 Oct 11;2(5). pii: e00251-17. doi: 10.1128/mSphere.00251-17. eCollection 2017 Sep-Oct. PubMed PMID: 29034325.

9: Lu J, Gu J, Li K, Xu C, Su W, Lai Z, et al. COVID-19 outbreak associated with air conditioning in restaurant, Guangzhou, China, 2020. Emerg Infect Dis. 2020 Jul [date cited].

Graphics Credit:

Graphic is from Shutterstock per their standard agreement.

Monday, July 13, 2020

Airborne Transmission Denial Dies Hard ........

I started this post as I left a staff meeting today on containing the coronoavirus. We had a similar meeting 2 months ago and at that point I added that there was airborne transmission of the virus.  The only comment I got was a condescending remark about how we don't know much about airborne transmission and we need to wait and see and blah, bah, blah. It was "as if" I did not know what I was talking about or any of the surrounding controversy.  To my surprise the same people today were sold on airborne transmission. They were even interested in HVAC issues and negative pressure rooms – all of the stuff I have been studying for 20 years.  Nobody mentioned UVC or air filtration.  I decided just to keep my mouth shut. Just like I usually do when politics seems to be the priority rather than science.  But the good news was undeniable.  Airborne transmission has much greater acceptance than it did prior to the current pandemic and there are clear reasons for it.

That staff meeting is a small part of a larger landscape of what airborne transmission advocates like me have been talking about for decades or longer.  Back in the days when I was working in an outdated building that had an HVAC system that was designed to contain heat rather than provide fresh air to dilute and remove airborne pathogens – I routinely observed the effects of this approach on myself and my coworkers.  Upper respiratory infections were endemic.  If one person came into that building with a severe form of a respiratory virus – most people got it. I can recall coming down with an acute flu-like illness one morning at work and getting ill so quickly and severely that I was barely able to make it home due to the cognitive effects.  I was close to delirium.

When you are in medical facilities, the party line is always “wash your hands”. I got the respiratory infections if I washed my hands 20 times a day or a hundred times a day.  The pandemic equivalent of that advice has been “don’t touch your face”.  But it is apparently safe to eat food that has been contaminated with SARS-CoV-2 because the virus is not infectious via gastrointestinal pathways.  The expert opinion is really based on the lack of evidence that eating food or touching food packaging is associated with SARS-CoV-2 infections.  We hear about the virus being infectious through the eyes and nose. It could be rubbed into the eyes from the face or into the nose by nose picking – but how common is that?  Certainly, washing your hands and not touching your face along with physical distancing at 6 feet seem like common sense rules.  But is that going to protect you?

I have never felt like any of those measures was enough and this week a letter came out pointing out the evidence for airborne transmission of respiratory viruses in general and for SARS-CoV-2 in particular.  I was pleased to see Dr. Milton as a co-author of this statement.  I have been reading his work for 20 years on airborne viruses in buildings of different design including the viruses that have been detected both in the air and the occupants of the building. This paper is a brief commentary specific to SARS-CoV-2 with a couple of generalities about airborne viruses and it is signed by 239 scientists who support it. 
The commentary starts out as an appeal to the medical community to recognize the potential for airborne spread of COVID-19.  Airborne transmission is defined as the release of droplets containing viral particles during breathing, coughing, sneezing, and any type of vocalization.  There is no doubt this happens. A distribution of droplet particle sizes occurs.  The larger droplets at a typical velocity settle out of the air in shorter distances typically in about 2 meters or 6 feet. The smaller droplets can travel much longer distances.  The authors cite an example of a 5 µm droplet at an original height of 1.5 meters and expelled at a typical indoor velocity travelling for “tens of meters” before it falls to the floor. This is typical airborne transmission and it will obviously not be contained by hand washing or physical distancing.

The authors on to describe some of the well-known scenarios where COVID-19 was transmitted despite no observed direct or indirect contact among the parties where the transmission occurred by video recordings.  They go on to cite other experiments demonstrating that several viruses (influenza, Middle East Respiratory Syndrome coronavirus (MERS-CoV), and respiratory syncytial virus (RSV) can all be spread by airborne routes. Although they don’t go into a lot of technical detail in the commentary, respiratory viruses are exhaled in normal tidal breathing.  The distribution and velocity of exhaled droplets will vary based on the way they are generated.  Infective viral RNA in small (5 µm) droplets from COVID-19 has been detected.

The critical sentence from this document follows:

“Hand washing and social distancing are appropriate, but in our view, insufficient to provide protection from virus carrying respiratory microdroplets released into the air by infected people.”

The is really a landmark statement from this group of experts. In my opinion it revolutionizes the approach not only to this virus but all respiratory viruses.  They all have access to the same type of spread and many have already been shown to have permeated heating and ventilation systems.  One of the main differences is virulence of the virus.  For example, smallpox or variola virus can cause an infection from the inhalation of a single viral particle (6).  Adenovirus, a much more common respiratory virus can cause an infection by the inhalation of as little as 6 viral particles (3).  Although adenovirus is potentially a flu-like respiratory virus, the main initiative at preventing the associated morbidity and mortality occurs in the military where a vaccination is used. The SARS-CoV-2 infections dose has been estimated to be about 280 particles – but the authors of one study suggest it is in the same ballpark of influenza virus and in that paper suggest that the amount of virus leading to infection in volunteers may be twice the amount of the aerosolized virus (5).

The main implication of airborne spread is that sustained inhalation of COVID-19 in poorly ventilated spaces of just being indoors increases risk of transmission. People who are coughing, sneezing, singing or engaged in any activity that results in forceful exhalation will expel small droplets at higher rates of speed and they will remain airborne for a longer period of time and travel much greater distances than the current suggested social distancing of 6 feet. 

To reduce the airborne transmission risk they have straightforward recommendations to avoid overcrowding (every additional person in the room is generating airborne droplets), have adequate ventilation, and supplement these measure with additions like HEPA filtration, germicidal UVC light, and exhausting room air rather than recirculating it. I can recall getting into an argument at one of my Avian Influenza Task Force meetings about a fast way to change the hospital ventilation system in the event of an influx of avian influenza patients.  Recall that the hospital was designed to retain heat by recirculating room air rather than exhausting it – like modern hospital rooms.  At the time, the counterargument was that it was just too expensive to build negative airflow rooms to prevent the flu virus from leaving the room with medical staff caring for the patients.  Most hospital rooms, even the ones I worked in that were built in the 1960s, had windows to the outside.  How difficult would it be to fit these windows with exhaust fans to the exterior of the hospital? 

This consideration is important now that there are political initiatives to reopen schools and other public places.  The ventilation systems of all of these places should be looked at and that assessment incorporated into the overall decision about how safe they are to open.  Further, there should be a systematic approach to how safe buildings are in general from the perspective of transmission of respiratory viruses.  A prospective approach that looks at how buildings in temperate climates need to be designed to minimize the spread of respiratory viruses needs to be a long term goal.  

It took a virus with heightened mortality and morbidity to raise awareness that physical measures rather than any available medication may be the best way to contain respiratory viruses.  Airborne transmission of respiratory virus denial dies hard - but hopefully it is being put to rest once and for all.  That should be a continued priority for everyone and momentum we cannot afford to lose.

George Dawson, MD, DFAPA


1:  Lidia Morawska, Donald K Milton, It is Time to Address Airborne Transmission of COVID-19, Clinical Infectious Diseases, , ciaa939,

2:  Erin Bromage.  The Risks - Know Them - Avoid Them.  Erin Bromage COVID-19 Musings.  May 16, 2020.  Link

3:  Yezli S, Otter JA. Minimum Infective Dose of the Major Human Respiratory and Enteric Viruses Transmitted Through Food and the Environment. Food Environ Virol. 2011;3(1):1–30. doi: 10.1007/s12560-011-9056-7. Epub 2011 Mar 16. PMCID: PMC7090536.

4:    Nicas, M., Hubbard, A. E., Jones, R. M., & Reingold, A. L. (2004). The Infectious Dose of Variola (Smallpox) Virus. Applied Biosafety, 9(3), 118–127.

5:  Schröder I. COVID-19: A Risk Assessment Perspective. J Chem Health Saf. 2020;acs.chas.0c00035. Published 2020 May 11. doi:10.1021/acs.chas.0c00035

Previous Airborne Transmission Posts from this Blog:

SARS-CoV-2 Is An Airborne Virus?

Viruses Are In The Air - Protection From Airborne Viruses

Hand Washing

New Twist On An Old Method To Kill The Flu Virus

Is It Time To Quarantine Air Travelers?


This statement from a recent Nature article:

"But this conclusion is not popular with some experts because it goes against decades of thinking about respiratory infections. Since the 1930s, public-health researchers and officials have generally discounted the importance of aerosols — droplets less than 5 micrometres in diameter — in respiratory diseases such as influenza."

from:  Dyani Lewis.  Mounting evidence suggests coronavirus is airborne — but health advice has not caught up.  Link.

Graphics Credit:

Graphic at the top is from Reference 1 based on the following CC License.  This is an Open Access article distributed under the terms of the Creative Commons Attribution- NonCommercial-NoDerivs licence (,

Monday, April 5, 2021

Airborne Transmission - Once Again!


I thought I would take time for a rare celebration on this blog.  Most of my writing is about probabilities and uncertain outcomes. In many cases I am responding to the same tired arguments from people who don’t understand science, biology, medicine or psychiatry. Those positions generally result in some political attacks based on that lack of understanding or some specific political agenda. The position I am referring today is the airborne transmission of viruses. Although it seems like a straightforward scientific issue it has led to as much controversy as any psychiatric topic. Despite a significant amount of literature out there on airborne spread, there has been nothing but resistance to the concept.

Nowhere was the resistance more evident than the advent of the current SARS-CoV-2 pandemic. Initially the message was that the virus was spread by fomites or intermediate size droplets that fall within a few feet following a cough or a sneeze.  Accordingly, social distancing at more than a few feet, decontaminating hands and surfaces were recommended to counter this mechanism of transmission. Many experts claim that most respiratory viruses with very few exceptions are transmitted this way. Those same experts claim that airborne transmission of viruses in smaller droplets travelling much longer distances was controversial at best. All of those conflicting ideas led to recommendations for no masks in February of 2020 followed by recommendations for masks in the next two months.  The mask recommendations occurred in the context of widespread shortages of personal protective equipment (PPE) for health care workers.   

I posted my qualifications on the matter (2 Avian Influenza Task Forces earlier in this century, being subjected to multiple respiratory virus epidemics at work despite rigorous hand washing, and studying the available engineering and viral data, and lengthy discussions with HVAC experts) and began to write about it on this blog.  My perspective is clearly that respiratory viruses are airborne and therefore will not be stopped by handwashing alone, that there are clearly engineering approaches to stop respiratory viruses that will work much better than just handwashing, and that there should be a major research and development effort on environmental designs to minimize and even stop respiratory viruses in homes and public building. In fact, as I type this I have selected a UVC device to be installed in my home HVAC system and it will probably be installed in the next month or two.  Many of those posts on this blog can be found here or by using the search term “airborne” in the search box.

The victory lap today occurs with a press release from the CDC today that I consider a bombshell in terms of the airborne transmission concept.  The press release is a quick read but it highlights why surface contamination is unlikely to be a significant factor:

“Quantitative microbial risk assessment (QMRA) studies have been conducted to understand and characterize the relative risk of SARS-CoV-2 fomite transmission and evaluate the need for and effectiveness of prevention measures to reduce risk. Findings of these studies suggest that the risk of SARS-CoV-2 infection via the fomite transmission route is low, and generally less than 1 in 10,000, which means that each contact with a contaminated surface has less than a 1 in 10,000 chance of causing an infection.”

And further:

“The principal mode by which people are infected with SARS-CoV-2 is through exposure to respiratory droplets carrying infectious virus.”

This information has been slowly presented over the course of the past several months.  For example, Dr. Fauci mentioned on several news outlets that cleaning all of the mail and groceries was not necessary because it was not considered a main route of transmission. A logical inference from that statement is why there is a concern about any surfaces at all unless there is a person with a known infection close by.  And by extension, if surface contamination is not that much of a problem why the concern about accidentally touching your face?  As Dr. Fauci typically states we now have the science behind the transmission and the recommendations can be adapted to the new findings.

The CDC press release does not come right out and say airborne transmission.  They continue to say respiratory droplets are the predominate mode of spread and the old document on respiratory droplets says nothing about differentiating between moderate sized droplets that typically fall to the ground within a 6-foot radius of where they are generated or airborne droplets that are lighter, spread past 6 feet from the generation site and remain suspended for longer periods of time.

Some of the comments on the press release have been much more definitive. The only reference to this post has a good timeline on the airborne controversy and this quote from atmospheric chemist Jose-Luis Jimenez: “If we took half the effort that’s being given to disinfection, and we put it on ventilation, that will be huge.”  In the same reference Germany has invested a half billion dollars in improving ventilation and indoor air quality.

Overall, it appears that the CDC is slowly coming around to the idea that respiratory viruses are transmitted via airborne routes, but some resistance is still evident in the press release they link to an earlier non-descript respiratory droplet transmission document.  There are many potential advantages to fully backing the airborne transmission concept (in addition to the available science).  Research and development is at the top of the list. In an early blogpost, I pointed out that UV decontamination was routine in buildings when I was a kid in a small town in northern Wisconsin.  The currently available UVC is much safer and very effective for killing airborne biological particles. From a clinical trials perspective, deployment of these systems on a large scale and following the number of respiratory infections in facilities with and without the technology seems like a fairly basic experiment.

It is also interesting to consider the resistance. There is undoubtedly politics in science and that can be a factor. There may be a medical intervention bias. In other words, we need some magical intervention like a vaccine, antiviral medication, or general polypharmaceutical modality that can either cure or prevent the excessive morbidity and mortality from respiratory viruses.  The track record there is some wins and many losses.  Every year various populations around the world are subjected to significant effects from flu-like illness that are nowhere as lethal as SARS-CoV-2.  Remarkably – everyone accepts this state of affairs until a more lethal virus comes around and affects a larger group of people.  There is politics as usual leading to irrational attitudes about viruses and physical interventions.  The appropriate environmental interventions may make mask refusers irrelevant at some point in the future.

The bottom line of today’s release is good news for all of the airborne virus crowd and I definitely consider myself in that crowd. I would still like to see the CDC modify their position on transmission in respiratory droplets and I think that is coming.  But most of all, I would like to see us get serious about using environmental measures to limit the exposure and spread of all respiratory viruses including the current one that has killed far more Americans than any influenza epidemic since 1918.


George Dawson, MD, DFAPA



1:  Lewis D. Why indoor spaces are still prime COVID hotspots. Nature. 2021 Apr;592(7852):22-25. doi: 10.1038/d41586-021-00810-9. PMID: 33785914.

2: Dietrich WL, Bennett JS, Jones BW, Hosni MH. Laboratory Modeling of SARS-CoV-2 Exposure Reduction Through Physically Distanced Seating in Aircraft Cabins Using Bacteriophage Aerosol — November 2020. MMWR Morb Mortal Wkly Rep. ePub: 14 April 2021. DOI:

3: Greenhalgh T, Jimenez JL, Prather KA, Tufekci Z, Fisman D, Schooley R. Ten scientific reasons in support of airborne transmission of SARS-CoV-2.  The Lancet (online).  Published 4/15/2021.  Current link

4: Tang JW, Bahnfleth WP, Bluyssen PM, Buonanno G, Jimenez JL, Kurnitski J, Li Y, Miller S, Sekhar C, Morawska L, Marr LC, Melikov AK, Nazaroff WW, Nielsen PV, Tellier R, Wargocki P, Dancer SJ. Dismantling myths on the airborne transmission of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). J Hosp Infect. 2021 Apr;110:89-96. doi: 10.1016/j.jhin.2020.12.022.  Current Link

Friday, February 9, 2018

Viruses Are In The Air - Protection From Airborne Viruses

Today was a good day.  I got up this morning and there on the morning news was a headline that I had been waiting to hear for at least 20 years.  There on CBS This Morning, Gail King was saying: "The flu can spread just by breathing so that is kind of scary."  That is kind of scary.  It is even scarier if you know that fact and listen to 20 years of how hand washing will prevent the flu. Hand washing is good only for surface contamination.  It does nothing for airborne viruses.  There is no known protection from airborne viruses other than biohazard environments.

I did not come by the knowledge easily.  Before medical school, I was a research assistance in a plant tissue culture lab.  Our job was to try to clone Loblolly Pine (Pinus taeda) and Douglas Fir (Pseudotsuga menziesii) trees from elite seed.  That required a sterile environment for tissue and media manipulations.  I spent much of the day working in a laminar flow hood bathed in sterile air.  We were not concerned at all about viruses at the time, but there were always experiments lost due to yeast and fungal contamination of the culture medium.  From there it was off to medical school and observations about just how contagious airborne viruses could be.  On some rotations the entire team was ill with respiratory infections.  I notice there is some movement today on telling physicians to stay home if they are sick.  If all of the people who were sick on one of these teams stayed home - there would be nobody there to take care of patients.  I did work with one attending physician who wore a surgical mask in a medicine clinic as a barrier to viruses.  Today we know that these masks are ineffective in blocking viruses.

The real eye opener came in practice.  For over 20 years I worked in an inpatient environment that was designed in the 1960s.  According to the HVAC experts I have consulted with, the environments in those days were designed to preserve heat.  They were not designed to provide fresh air in a manner that would minimize the risk of airborne virus infections.  All of the rooms in that environment had individual radiators equipped with fans.  The room air was recirculated.  At the top of each room was a 12" x 12" square vent that moved the air down  the length of the building to a few air shafts that traveled up and down between floors.  I was reassured that there was adequate air flow and that it was measured.  I was provided with some diagrams that did not really show any solid data.

In that environment, airborne viral infections ran rampant.  They were acute care psychiatric units - so many of the patients directly admitted had influenza.  It was just a matter of time before it was picked up by the staff and then transmitted from person to person.  Getting one or more of these infections predictably was quite depressing.  As anyone knows - a severe case of the flu disrupts your entire life.  The polypharmacy that the staff was subjected to was also impressive.  Long complicated courses of antibiotics for secondary infections after the flu had passed.  Exposure to prednisone and methylprednisolone for post-viral bronchitis and asthma exacerbations.  All of the infected staff were schooled in proper handwashing techniques by Infection Control.  During flu season we were basically adrift in tight confines - breathing contaminated air.  It is well documented by studies in hospital and other building environments that there are a significant amount of viral and other pathogens in the air that can be collected by a number of means (2).

The other enlightening experience involved my participation in two Avian Influenza task forces.  Practically all of the work that I saw being done seemed to ignore the issue of airborne spread.  That was probably at least in part due to the fact that the hospital capacity of negative air pressure rooms would be immediately overwhelmed.  At that point, I heard one expert say: "You need to have an N95 respirator mask on as soon as you walk through the door of the hospital."  The efficacy of those masks in preventing flu transmission is limited but probably offers some moral support when you are walking into an environment that is full of highly lethal influenza virus. Most of the planning done on the task forces seemed to be designed to prevent a large surge of patients going to the emergency department, providing psychological support to the overwhelmed, and hoping the military really did have that palette full of Tamiflu that they keep showing us in the PowerPoint presentations.

One of the questions I frequently get is - what about the vaccine?  Designing an effective flu vaccine is part science and part speculation.  It involves anticipating the viral strains of the next epidemic and that is difficult to know with certainty.  This is the first year that I can recall public health officials coming out with the actual numbers.  Most Americans have heard that this years vaccine is about 30% effective and that the most effective vaccines are 50-60% effective.  The argument is that the vaccine improves herd immunity and decreases the spread of the virus.  Exactly how much of that is cancelled out by broad exposure to an airborne virus is unknown, but I do think that is sufficient reason to always get the vaccination.  I was my own experiment for about 30 years.  I reacted to an anti-rabies duck embryo vaccine in my 20s and did not get the vaccine for the subsequent years.  I finally saw an allergist/immunologist about 7 years ago and have been getting the vaccine since.  Since then there has been no detectable change in the number or intensity of flu-like illnesses that I have developed.  During the time unvaccinated, I had the experience of developing an acute fever after being exposed to a colleague with the flu, taking Tamiflu (oseltamivir) and having the symptoms resolve within 24 hours.  There is a chance that a universal flu vaccine can be designed and I hope that is true.  In the meantime we are left dealing a number of airborne viruses and altering the environment seems like the best approach.   

Flashing forward to this morning.  Part of the story focused on Donald K. Milton and the work he did in designing a machine to sample flu viruses in a natural setting.  Other sampling techniques have typically involved subjects breathing according to protocol into a device.  The large reverse megaphone type of device that this group is using allows air flow past the face at a regular rate.  It allows research subjects to breath normally and sample their expired air for influenza virus.  The sample in this case was a group of healthy 19-21 year old college students with a high asthma prevalence (21%) and a low influenza vaccination rate.  Nasopharyngeal (NP) sampling and RNA detection was used to diagnose influenza and RNA copies.

The subjects were asked to breathe, talk, cough, and sneeze into the sampling device with no constraints on that activity.  They were asked to recite the alphabet at 5, 15, and 25 minutes.  Coarse droplets (> 5 μm ) and fine droplets (≤ 5 μm and >0.05 μm) were collected separately. Influenza virus was recovered from 89% (N=150) of the NP swabs and 39% (N=52) of the fine aerosol sample. This is positive proof that just breathing (tidal volume breathing) results in dispersing infectious viral particles into the air.  The influenza cases did not sneeze during the collection period. Viral shedding was greater for men.  Women coughed more frequently but shed significantly less virus per cough.  Increased BMI produced increased viral shedding in the fine aerosol and the speculation was that increased BMI causes a tendency for small airway collapse and that may lead to increased shear forces that produce the fine aerosol.  Since sneezing was not observed - it was not considered necessary to produce the fine or coarse aerosol.  Coughing was present and was a significant predictor of both coarse and fine aerosols.
This is a critical paper that I hope that all public health officials, administrators and architects will take note of.  It takes more than handwashing and coughing into your sleeve to protect people against influenza virus.  It takes recognition that this is an airborne virus and it is aerosolized by breathing.  Physicians are on the front lines when it comes to virus exposure and we need better barrier methods to prevent exposure.  During flu season I sit in a 8 x 10 foot office and talk with people who sit about 4-5 feet away from me.  I talk with most of them for 20-30 minutes or about the length of time of the experiment.  The symptoms listed in the severity scale below are incorporated into my review of systems and there are some days when 100% of the people I see have a respiratory infection.  If they all have influenza, 30% will leave aerosolized virus in my office just from talking with me.  Is there a better way to do things to minimize exposure?

I think it starts with building design.  Rooms that are all individually vented to the outdoors on both the intake and exhaust side.  Heat exchangers exist today and can be used for this purpose.  Starting with influenza as the model and optimizing air flow and humidity to decrease infection rates is a start.  Interviewing people across barriers or using television cameras is another possibility especially if vulnerable populations need to be protected from consultants who may be carriers. The tremendous lack of psychiatric infrastructure compounds the problem.  Although the building that I refer to was ultimately replaced and torn down - psychiatric services are typically housed in the oldest and most run down buildings.  Today jails have replaced psychiatric hospitals and the jail infrastructure is no better.  It is common to see patients who are acutely ill with influenza in these settings.  Psychiatric beds need to be in an environment that reduces the transmission of infectious diseases including airborne viruses.   

The work does not stop at that level.  The ways hospitals and buildings are cleaned needs to be thoroughly investigated.  Carpet and floor cleaning equipment clearly leads to the dispersion of particles in the carpeting or on the floor.  I am not aware of any initiative to make sure that cleaning the surfaces in buildings does not leave the air contaminated.

My advice is to spread the word and this reference to anyone who is unsure about airborne viruses. I am hopeful that at some point over the next 10-20 years the environmental aspects of the problem will be addressed.  That will change the nature of influenza transmission as well as a host of other viruses that get sampled in the HVAC systems of old buildings - probably long after the occupants have been infected by them.

George Dawson, MD, DFAPA


1:  Yan J, Grantham M, Pantelic J, Bueno de Mesquita PJ, Albert B, Liu F, Ehrman S, Milton DK; EMIT Consortium. Infectious virus in exhaled breath of symptomatic seasonal influenza cases from a college community. Proc Natl Acad Sci U S A. 2018 Jan 30;115(5):1081-1086. doi: 10.1073/pnas.1716561115. Epub 2018 Jan 18. PubMed PMID: 29348203; PubMed Central PMCID: PMC5798362

2:  Airborne Virus Monitoring: unedited search


Image at the top uses a crowd infographic from Shutterstock per their licensing agreement.

Supplementary 2:

This is the approach the authors used to scoring the flu symptoms severity in their paper (my interpretation) (click to enlarge):

Sunday, January 11, 2015

Hand Washing

I washed my hands 40 times yesterday and used disinfectant hand cleaner at least 10 times when I did not have immediate access to water and soap.   My hand washing technique was validated by  an infection control nurse who was trained to monitor appropriate hand washing.   I also wiped down the table in my office and the chair about 3 times with disinfectant wipes.  I am careful not to touch my food or my face.  I have an air cleaner running in that office from about 8AM to 6PM that has a UV lamp designed to kill viruses.  Despite all of that I am in day #5 of a flu-like illness (cough, myalgias, fatigue, but no fever).

I don't have obsessive compulsive disorder.  I live in Minnesota and it is peak season for the annual influenza epidemic.  I actually take more precautions.  During flu season, I avoid the public.  I used to belong to a gym, but set up my basement so I could do my workout routine at home.  Exercise equipment is a known reservoir of viruses and bacteria.  I have also been in a gym when it sounded more like a hospital ward due to the hacking and coughing.  I avoid movie theaters for the same reason.  I have been doing these same rituals for the past twenty years, initially because I thought I was allergic to influenza vaccine and did not want to catch the flu.  I have been fairly  successful in avoiding the flu, but not so successful in avoiding practically every other respiratory virus.  For twenty three years I worked in an old building that was designed to contain heat rather than clear respiratory viruses.  In that environment, once a virus is introduced there is a predictable epidemic (sometimes within a few days) affecting the entire staff.   Modern employment disincentives (the finite paid time off with no sick time system) keeps all of the ill people working.  They would rather work than lose vacation time.  That keeps the epidemic going.

 Throughout the flu season people at risk are told the same things.  Wash your hands, cough into your sleeve, stay at home if your are ill and get the flu shot.  Unfortunately all of these measures is not enough to prevent infection by airborne viruses.  Face masks help.  A study of college dormitory dwellers showed that hand washing and wearing a mask as well as wearing a mask only offered more protection against influenza like illness relative to a control group.  They used the term modest, but I would call about a 10% difference in infection rates weak at best.  In their study they looked at three groups of students in college dormitories.  The groups and the attack rates of flu-like illness (FLI) included controls (no intervention) 117/552, face mask only 99/378, and face mask and hand hygiene 92/367.   The authors tried to control as many measures as possible but there are a lot of reasons why experimenting on college students is problematic.  In terms of the basic methods hand washing or use of hand disinfectants is considered to have a small but significant effect on the transmission of respiratory viruses.  The effectiveness of masks depends on the fit of the mask, the physical characteristics of the environment and the virus itself.  One study (4) showed that a tightly sealed N95 respiratory mask would block 94.8% of influenza virus and a poorly fitting mask blocked only 56.6% of the virus.  

The process of creating infectious droplets is an interesting physical process.  There are  current estimates that show normal breathing for 5 minutes creates a few droplets through the process of atomization.  A single strong nasal expiration results in a few hundreds droplets with a few in the 1-2 µm in diameter.  Counting loudly creates a few hundred droplets in the 1-2 µm range.  A single cough produces a few thousand and a single sneeze produces a few hundred thousands to a few million 1-2 µm droplets that can contain viral particles.  There is a a video of what happens to those millions of sneeze generated particle in an airplane.  It might be a good place to wear a mask but that assumes that you have it on before the sneeze.  Atomization can also occur from vomit (10viral particles per ml) and feces (1012 viral particles per gram).   Those routes of transmission have been important for SARS and Norwalk Like Viruses.

The most recent estimate of costs due to building influenced communicable respiratory infections was about $10 billion in direct treatment costs and indirect costs of $19 billion in lost productivity and $3 billion in performance losses.  Asthma is significantly affected and possibly caused by airborne respiratory viruses and that is another $18 billion in costs ($10 billion direct and $8 billion indirect).  My interest has been in trying to promote more attention to the problem especially at the environmental levels.  Just altering airflow characteristics or making other changes in the humidity and air temperature can reduce the infectivity rates by as much as 50%.  Apart from the cost, it has an immeasurable effect on employee morale.  It is difficult for anyone to work knowing that at least one month out of the year they will have significant symptoms of a respiratory syndrome.

Why did I post this and in particular on a psychiatry blog?  In my 23 years of inpatient experience, respiratory viruses plagued the staff and the patients we were treating.  Any attempt I made to change that from a non-medical environmental perspective was met with no response.  I think that is the standard response of our culture and most employers.  Mental health settings tend to be located in older buildings and older parts of health care campuses and respiratory viruses is likely a bigger problem.  Health care settings should be leaders in developing environments and infrastructure that is hardened for the airborne respiratory virus problem.  It is imperative as a healthy environment for workers and patients and it provides reserve capacity in the event of a more widespread pandemic.  I have also made some observations about the impact of FLI on psychiatric symptomatology - both improvements and worsening.  There is a increasing literature on the effect of cytokine signaling on brain function and I suspect that is what I was seeing, but more research is needed.    

In the meantime, keep washing your hands.  Keep in mind that this post is only about airborne infections.  Any physician with direct contact with patients needs to wash their hands after seeing a patient and before seeing the next patient.  Most hospitals have a rule that hand washing needs to occur every time a physician enters or leaves a room.   For airborne respiratory viruses, it is not enough but it decreases the risk of respiratory infections to a slight degree.  My guess is that the more highly infectious airborne viruses are much less containable with hand washing and that environmental measures involving airflow, relative humidity, and possibly filtration and UV sterilization is what is required.  Anyone planning new construction should focus on these measures and obtain appropriate heating and air conditioning consultation with an emphasis on reducing respiratory infections.

George Dawson, MD, DFAPA


1:  Aiello AE, Murray GF, Perez V, Coulborn RM, Davis BM, Uddin M, Shay DK,Waterman SH, Monto AS. Mask use, hand hygiene, and seasonal influenza-like illness among young adults: a randomized intervention trial. J Infect Dis. 2010 Feb 15;201(4):491-8. doi: 10.1086/650396. PubMed PMID: 20088690.

2: Verreault D, Moineau S, Duchaine C. Methods for sampling of airborne viruses. Microbiol Mol Biol Rev. 2008 Sep;72(3):413-44. doi: 10.1128/MMBR.00002-08. Review. PubMed PMID: 18772283; PubMed Central PMCID: PMC2546863.

3: Morawska L. Droplet fate in indoor environments, or can we prevent the spread of infection? Indoor Air. 2006 Oct;16(5):335-47. Review. PubMed PMID: 16948710.

4: Noti JD, Lindsley WG, Blachere FM, Cao G, Kashon ML, Thewlis RE, McMillen CM, King WP, Szalajda JV, Beezhold DH. Detection of infectious influenza virus in cough aerosols generated in a simulated patient examination room. Clin Infect Dis. 2012 Jun;54(11):1569-77. doi: 10.1093/cid/cis237. Epub 2012 Mar 29. PubMed PMID: 22460981.

5. ASHRAE (American Society of Heating, Refrigerating, and Air-Conditioning Engineers) ASHRAE Position Document on Airborne Infectious Diseases Approved by ASHRAE Board of Directors January 19, 2014 Expires January 19, 2017.  - This is an interesting approach that looks at how to look at engineering approaches to airborne infectious particles and come up with a better approach.

Supplementary 1:  Various inhalers used over the past year following a probable rhinovirus exacerbation of asthma in January of 2013.  This is a rapid way to meet your annual deductible.

Supplementary 2:  Graphic of pathogens detected per week is from the Minnesota Department of Health web site.

Saturday, February 10, 2018

New Twist On An Old Method To Kill The Flu Virus

Right after posting the previous article on the latest confirmation that influenza virus is airborne, I came across and article in Nature that had me thinking back to my childhood.  I remember walking into an insurance office on Main Street in our small town.  There was something strange about the environment.  Up next to the ceiling were ultraviolet lights.  The lights were shielded so that they only reflected up toward the ceiling.  I asked my parents what they were and got the answer: "They are there to kill germs."  My head was spinning from that answer: "There are germs in the air? They are up next to the ceiling? What kills the germs that are down here next to me?" Yes - I was a neurotic little kid.

Over time I learned a little about the nature of ultraviolet light, especially that it could cause eye damage if you looked right at it. As I got into the 1970s, the hippie era, and psychedelia that because less important.  There were UV lights everywhere - blacklight posters and the detergent residues in clothing phosphorescing white light after it has been activated by UV light.  In some environments everyone was bathed in UV light.

Today most Americans are aware of UV light because of sunscreen and eyeglass applications.  Long and medium wavelength (UVA and UVB) and not absorbed by the ozone layer.  It is recommended that glasses block 100% of the UVA and UVB for maximum eye protection.  That can also be designated as UV400 because they block all UV light from 280-400 nm.  The part of the UV spectrum is also important in sunscreens.  UVA penetrates the skin to a deeper level and is responsible for damaging keratinocytes, cataracts and causing premature aging.  UVB is responsible for burning and carcinogenesis.  UVA and UVB are considered both carcinogenic and carcinogenic.  Even those UV light has been known to be germicidal for over 80 years that human toxicity has limited the application.

UVC (100-280 nm) is blocked by the ozone layer and therefore is not a consideration in either eye or skin protection.  It is considered to be the part of the spectrum that is potentially germicidal and that is where the latest application begins.  In this report the authors used filtered 222-nm light sources in an experiment to see if they could inactivate aerosolized H1N1 influenza virus.  They were able to accurately measure the light dose and estimate virus inactivation using an epithelial cell model that measured infected cells by fluorescence.  The authors aerosolized the virus into a UV irradiation chamber.  The chamber had a total volume of 4.2 liters and had a characteristic particle distribution of 87% < 0.3 - 0.5 μm, 11% 0.5 - 0.7 μm, and 2% > 0.7 μm.  Those are characteristic particle distributions of airborne droplets that occur with breathing, talking, and coughing.

An air flow of 12.5 L/min through the chamber was noted and they calculated that this meant a single droplet passed through the chamber in about 20 seconds.  I think that is significant because it in unlikely in a typical building that a person would be standing in an air current moving that quickly. In other words, if the aerosolized virus can be inactivated in an airstream moving that quickly - it might have practical applications in most environments.  The authors were able to construct a dose response curve showing that at a dose of 2 mJ/cm2 viral survival is negligible.

I found this to be extremely impressive work because it clearly shows that airborne influenza virus can be inactivated using a far-UV source that is much safer to humans than previous germicidal UV sources.  Furthermore the sampling and intervention characteristics seem to be very realistic in terms of what might be encountered in public facilities.  The real question seem to be whether any commercially available air cleaner/purifiers come close to matching the characteristic of this experiment.  A preliminary search of these devices shows that the airflow characteristics are typically not listed, very few use far-UVC light sources (most use germicidal 254-nm sources shielded in the device), and none are certified in terms of how much virus they kill. They typically suggest that germicidal UV light is all that is needed for air purification.  There is also the question of whether using a device in your office at work confers any degree of protection once you leave that office and start walking down the hallways.  My speculation is that it would not, but the amount of virus generated in your office may be a significant variable.

The authors themselves suggest that if their results are confirmed far-UVC represent a significant opportunity to limit the transmission of airborne disease and that it could be widely used in medical offices and buildings as well as public areas where disease transmission is common like airports and airplanes.

I am hoping that this areas of research yields rapid results and broad implementation.

George Dawson, MD, DFAPA 


1:  David Welch, Manuela Buonanno, Veljko Grilj, Igor Shuryak, Connor Crickmore, Alan W. Bigelow, Gerhard Randers-Pehrson, Gary W. Johnson, David J. Brenner.  Far-UVC light: A new tool to control the spread of airborne-mediated microbial diseases.  Scientific Reportsvolume 8, Article number: 2752(2018).  doi:10.1038/s41598-018-21058-w

Graphics Credit:

Table 1, Figure 1, and Figure 2 are all used from reference 1 per the Creative Commons Attribution 4.0 International License.

Friday, October 17, 2014

Being Honest Won't Save You - Lessons In Medical vs. Business Accountability

Every now and again I flash back to a surgical rotation that I was doing at an old county hospital.  It was quite run down.  We had a large surgical service comprised mostly of people with gunshot wounds, cancer patients, and people who were in long term care hospitals for mental illness who developed acute surgical problems.  Most of the patients who had gunshot wounds had been shot by the police and they had police officers posted outside of their doors.  On some days it seemed like there were a lot of police officers outside of every other door for quite a distance down the hallway. We did two sets of rounds - in the morning after the surgical procedures and another set of rounds at about 6 or 7 PM.  The evening rounds always ended under fluorescent lights in what is probably a long abandoned nurses station.  In this particular case we are rounding with a senior surgeon and a junior surgeon.  The senior surgeon has just demonstrated how much he knew and how little the residents knew about the effects and importance of gastrointestinal tract hormones.  After a few moments of uneasy dead air, the junior staff asks the intern: "What was Mr. X's calcium level this afternoon?"  The labs were typically run at 4PM and in those days we would have started to see results at about 5 or 5:30, but we were all rounding at that time and attempting to answer questions about GI hormones.  The conversations went something like this:

Staff MD:  "What was Mr. X's calcium level this afternoon?"
Intern:  "I don't know."
Staff MD:  "What?  I expect you to run this service.  How can you run this service if you don't know what Mr. X's calcium level is?"

The team got quite nervous in situations like that.  Training in medicine puts you directly in the line of fire or at least it used to.  These days commentary and affect like I witnessed that day might lead to some type of disciplinary procedure for the staff physician.  Something that could be passed down on credentialing forms and haunt a physician for the rest of his or her career.  A type of pseudoaccountability arranged by the bean counters essentially to manipulate physicians.  In this case, it was considered to be a learning experience and culturally appropriate.

In this case the intern in question seemed to recover.  Things went well for another few days.  And then he was gone.  The rumor was he was asked about another lab value, gave an answer that was slightly incorrect as in no physiological difference between the answers. He was fired for making up the answer.  Keep in mind that this incident occurred at a time when there were hundreds of lab values to track and the technology was at a primitive state relative to what is currently available.  The computers were slow and getting results took a lot longer.  Medical students, interns and residents had to write the labs down on cards using whatever shorthand they could devise.  In the process some data was memorized but not all or most of it.  But the difference here is that the integrity of the answer was called into question.  The assumption was that you either know the answer for sure  or you say you don't know.  There are no near misses.  The judgment is that you made something up and that is unacceptable.  In the years since, I have seen quite a few colleagues fall by the wayside as a result of similar incidents or what were considered to be errors in judgment by the senior faculty.

In recent times, I think there is a tendency to lump this behavior in the category of senior faculty being abusive toward physicians in training.  That certainly may be true, but it is also true that it draws a very clear line about what you need to be doing as a physician as opposed to what you may have done in your undergraduate major.  You can no longer make things up like you used to do in your philosophy and English literature classes.  You have to be brutally honest about what you know and what you don't know.  I don't think there is a physician alive who will not tell you that knowing this is one of the most critical aspects of training as a physician.  The ultimate test of whether you are patient centered is whether you will not try to protect yourself - but whether you can be brutally honest even in a situation that may put you at risk professionally.  Can you acknowledge mistakes, lapses in judgment and most importantly a lack of knowledge or expertise?  Patient safety depends on it.  That atmosphere also has the effect that you show up for work.  If you know that you are a target for any faculty who want to criticize you, you tend to want to know everything there is to know about the patients on your service.  In contrast to the events where the question does not get answered I have seen residents give tutorials on ventilator settings or pressure recordings by Swan-Ganz catheters.  They were motivated to some degree by knowing that teaching staff would be asking and their assessment depended on their answers.  

The reason for that introduction is that it frames the backdrop for a discussion from a financial thread with a very interesting title: Will Ebola Vanquish the MBAs Who Run Our Hospitals?  It is a title by a blogger and certainly eye-catching.  I have followed this blogger for a number of years and agree with a lot of what she has to say about the way financial services are managed in this country.  I have disagreed with her about some of her medical opinions, but this post is something that I can agree with.  I was recently e-mailed about my tendency to selectively find research that supports my opinions.  I consider this to be more opinion to support my opinion.  Research on how businesses manage medicine is as scant as research on management in general.  Business people tend to produce papers suggesting there are deficiencies and then say how they will correct those deficiencies.  There is really hardly any research to support business opinion.  The opinion in this case looks at a topic I frequently comment on - how can business people with no medical or scientific training manage physicians and medical facilities?  In my opinion they clearly can't but let's look at what is presented in this article.

The basis for the article is essentially opinion in the press and the opinion of a medical blogger.  The conflict-of-interest here that is usually glossed over is that any journalist, newspaper, or blogger wants the public reading their stuff.  It will be provocative or sensational.  A measured analysis is not typically seen.  For example the comparison of staff infection rates between the staff at Dallas Presbyterian Hospital (DPH) and Doctors Without Borders (DWB) in Liberia seems pointed, but the obvious question is whether the infections rates vary with experience.  For example did the DWB staff in the earliest stages of their involvement have infection rates as high as were portrayed in the DPH staff.  Can a direct comparison be done without that information?  The highlighted emergency department (ED) problems are similarly problematic.  If you pull up the Internet sites for the DPH system of care they are affiliated with a number of inpatient psychiatric units.  Is the wait time a reflection of a large pool of chronically mentally ill or poorly stabilised psychiatric patients being stuck in the ED?  If that is true it would still be consistent with some of the authors concern about the lack of public health concern and the fact that lower socioeconomic classes come face to face with the wealthy in such settings.  It is also an aspect of the mismanagement by rationing that is pervasive with systems of care managed by large businesses.

I have first hand experience with infection prevention in hospitals and attempt to stop widespread outbreaks from respiratory viruses.  Keep in mind that the Ebola virus is not an airborne virus.  All of the remarks in this paragraph are about airborne viruses especially Influenza virus.    For a number of years I was extremely disatissfied with the epidemics of respiratory viruses that swept through the staff where I was working.  Employer rules about paid time off only worsen the situation because the incentive is to work when you are sick to prevent loss of vacation days.  But the most frustrating part of the problem (apart from being sick 3-5 times a year) was that the employer had no real interest in doing anything that might reduce the risk of infections.  The intervention I suggested was just improving air flow in certain buildings.  The standard reply that you get is "wash your hands and cough into your sleeve."  Those are certainly common sense measures but as far as I could tell had no impact on the rate or severity of infections each year.  Hospital administrators everywhere seem to be in denial of the fact that airborne pathogens exist and washing your hands and coughing into your sleeve will not protect you against airborne pathogens.  I was also a member of two different Avian Influenza task forces.  At the time there was much uncertainty about a widespread epidemic that could not be contained.  We were setting up for the worst case scenario of thousands of people (both infected and not infected) coming into EDs and how to triage and treat people.  After years on these task forces it became apparent to me that nobody was really interested in planning for the prevention of mass casualties from an airborne virus.  There was no planning for any additional negative pressure airborne isolation rooms and no planning for any additional bed capacity in the event of a widespread epidemic.  There was planning for what to do with the expected bodies.  In the end it seemed that all of our hopes were pinned on a rapidly disseminated vaccine or antiviral medication.  The specifics of the antiviral medication were murky.  We were shown a picture of a large pallet of oseltamivir sitting in a warehouse somewhere.  From a business administrator's standpoint, planning to use imaginary resources from the government is always preferable to more functional planning because it is free.  My personal experience in this area from volunteer work on respiratory viruses is entirely consistent with the notion that health care businesses are not administered in a way that is consistent with public health needs in the case of infectious epidemics.

The Naked Capitalism article contains analysis from Roy Poses, MD of the Health Care Renewal Blog.  He looks at inconsistencies in the media and concludes that this is another case of health care leaders being untrustworthy.  That appears to be a central theme of his blog and he goes on to criticize them for being inconsistent, suppressing information from employees that may be critical to public health, and having an inflated sense of self importance.  These patterns are easily observed by physician employees of health care organizations.  For at least a decade after passage of The Health Insurance Portability and Accountability Act of 1996 (HIPAA) it was impossible to get necessary information from health care organizations, even in the case of needing to provide emergency care.  I would routinely request information and even send a HIPAA compliant release signed by the patient and I would get a blank form the other hospital saying that my patient had to sign their form and fax it back.  Hospital administrators were a big part of that process.  It is common for the clinical staff to be buffeted by the next big idea from their administrator.  That can range everywhere from high school style pep rallies that are supposed to improve employee morale to a new productivity system that is guaranteed to get even more work from physicians.  In every case, the administrator in charge could be making 2-5 times what the average physician makes for considerable less accountability, practically no "evidence based" methodologies, and no measurable productivity.  As pointed out in the article, public relations is much more of a factor in the CEO's reputation.  From the article:

" On Health Care Renewal we have been connecting the dots among severe problems with cost, quality and access on one hand, and huge problems with concentration and abuse of power, enabled by leadership of health care organizations that is ill-informed, incompetent, unsympathetic or hostile to health care professionals’ values, self-interested, conflicted, dishonest, or even corrupt and governance that fails to foster transparency, accountability, ethics and honesty." 

There are additional lessons from the decimation of mental health care in the United States, especially care delivered at tertiary care and community hospitals.  There is perhaps no better example of low to no value service that is the direct result of non-medical management.  There is no coordinated public health effort either improve the care of psychiatric disorders or specific high risk behaviors like suicide or homicide.  The standard approach is rationing of both care that would result in stabilization but also bed capacity that would alleviate congestion in emergency departments.  There should be no debate on cost, inpatient psychiatric care is without a doubt the low cost leader and is set to match reimbursement from a high turnover low quality model.  Psychiatric services in clinics and hospitals have a lot in common with what Dr. Poses observes on the administrative side of many health care organizations.

Responding to the question of  "Will Ebola Vanquish the MBAs Who Run Our Hospitals?" - my answer would be no.  It is always amazing to consider how so many people in business with so little talent can end up running things and making all of the money essentially through public relations, advertising and lobbying politicians.  There is no shortage of self proclaimed administrator-visionaries.  The author here should know that their power is consolidated around the same strategies that have worked for the financial services industry.  Managed care business strategies based on no science or input from physicians are now in the statutes of many states and in federal law.  They have successfully institutionalized business strategies designed to return profits to corporations as the rules that govern healthcare.  The pro-health care business lobby essentially gets what they want and the professional organizations are weak and ineffective, but continue to browbeat their members for contributions.  Administrators have a lock on running health care and demanding whatever accountability they demand from health care professionals while having no similar standards for themselves.

I can't think of a worse scenario for addressing potential public health problems whether that is an infectious epidemic or the continued mental health debacle.

George Dawson, MD, DFAPA

Supplementary 1:  Kaiser Family Foundation brief PowerPoint and Infographic on the current Ebola out break.

Supplementary 2:  I decided to add the above table comparing the accountability of physicians with business administrators.  Certainly there may be some things I have missed on the business administrator accountability so if I missed anything please let me know and I will include it.  From what I have observed, health organization and hospital CEOs are typically accountable to a Board of Directors that has very little physician or medical representation.  Often the Board is stacked with people who rubber stamp what the CEO wants to do.  Like the web site referred to in the above post there is often an aura that the CEO and the Board have visionary-like qualities that are based on public relations and advertising rather than any academic work or actual results.  I have never really seen an administrator who was a visionary or knew much about medicine - but  you can certainly read their proclamations about how medicine should be reformed on a daily basis in many places on the Internet.  The usual argument for all of the physician accountability is that it is a privilege to practice medicine and therefore regulation of physicians needs to reduce the privacy rights of physicians and subject them to much closer regulation than other professionals.  Why wouldn't that approach apply to the people who actually determine whether a patient gets health care, medications or a specific benefit?  Why wouldn't that same logic apply to the people who really run the health care system?