Biologic barriers are present from conception. Surrounded by the amniotic membrane, we are protected from most pathogens. Upon its rupture and our ride down the birth canal we start the self versus society struggle.  Hepatitis B, polio, rotavirus, diphtheria, tetanus and pneumococcal vaccinations are our initial immune barrier. Child proofing mechanical barriers (plug locks, stair locks, edge protectors) are present during our formative years. Car seats and later seat belts protect us from motor vehicle morbidity. Science has driven these medical protections and public health measures have orchestrated their distribution to the public and their acceptances as standards of care.

Societal barriers have protected humans for eons from human aggression, accidents and microbes. The Caves of Lascaux  protected Paleolithic man, The Great Wall of China retarded invasion by the Mongols. The Roman emperor Hadrian built his namesake “wall” in Northern England to keep out the “barbarians.” Ramparts and moats around European castles in the Middle Ages slowed the devastation wrought by the Vikings. In our lifetime we put up with anti-terrorist barriers at TSA checkpoints at all U.S. airports. Physical barriers and screening techniques have been shown over time to decrease disease and death from outside threats to our well-being.

Our protection from COVID-19 now demands a barrier to our nasopharynx. We are now safely surrounded by our homes’ four walls and limited “world” contact through our UPS and Amazon delivery services. In order to integrate into society we need extra protection from the virus. A mask or “facial condom” could provide us with the protection and turn human interaction into an acceptable risk. We are now familiar with the N95, surgical, and home-made masks. We have YouTube videos of media celebrities constructing masks. Now,  “mask science” is the next logical step to assure that our efforts are working to prevent Covid-19 transmission. What we really need is some evidence based guidelines developed from a controlled study.

 The geometry is well known: N95 keeps out 95% of particles that are as small as 0.3 microns; droplets containing COVID-19 are 50 microns or less. Droplet spread is 6 feet, more if sneezing or aerosol transmission is involved from the contact. What we don’t know is what materials and layering are most effective against virus spread when used in a real world scenario.

Compliance and comfort are inextricably linked. When I donned a mask in the OR, my face felt like I was in the microclimate of Miami during the summer and my eyeglasses fogged up like winter in London. We have designers and aerosol engineers that can overcome “wearability” issues that could lead to improved compliance. We have industry and universities that have the capability of testing combinations of fabric under simulated and actual environmental conditions.  Distribution capabilities are available to send masks to every household in the United States utilizing the Postal Service.

Americans have internalized the use of seatbelts and TSA screenings in my lifetime. Introducing and complying with  a “new fence” is easier when the alternative may be a painful respiratory death. Wearing a fashionable, comfortable and effective face mask should become the “new normal.”  The design, efficacy and distribution is simply just one more barrier for science to overcome.

Humans have constructed great civilizations in only 10,000 years, surmounting  challenges and establishing the supply chains that provide food, clothing and shelter for the billions that inhabit this planet.  Yet we are impeded by one major human foible: selective long term memory loss in order to cope with the next medical task at hand. What do I mean?  Take human memory and the history of contagious disease in society. We learn, at an early age, that American and international history were shaped by infectious disease. Early settlements in Virginia in the 16th century failed due to malaria outbreaks. In 18th century Philadelphia, an outbreak of yellow fever forced our founding fathers to flee the city.  Bubonic plague outbreaks in Europe in the 6th and 14th centuries killed 50% of the inhabitants and changed Roman and Medieval society. The medieval citizens fled the crowded cities for pastoral domiciles sensing that social distancing would prevent the deadly illness. Great armies were felled by typhus and cholera during the Napoleonic Wars and World War II.  We don’t have to go back very far to see a world where our parents and grandparents had a stark recollection of epidemic infectious disease. Diphtheria, polio and measles, to name a few childhood illnesses were part of their daily reality. Parents banned their children from community swimming pools, recognizing that distancing them from the source was paramount.  I, born in 1953, recall fellow students in my class with leg braces from polio following summers spent hospitalized. As I entered medicine in the 1970’s, there were reminders of past epidemics on the wards. I rounded in iron lung wards in Rancho Los Amigos Hospital in Downey, California. I ambulated the pediatric wards at L.A. County-USC Medical Center, puzzled by the prominent parapets outside the patient rooms. “They were there so that physicians could round and quarantine themselves during polio outbreaks,” my attending noted.  Again, in the early 1980s a mystery illness with a severely immunocompromised picture in the patient appeared in daunting numbers. The AIDS epidemic was upon us as we scrambled for its cause and cure. As time passed, the memories of these debilitating epidemics receded whereupon complacency and the rise of the anti-vaccination movement became the cause celebré of the 1980’s and beyond. The resurgence of the measles due to lack of sufficient vaccination in the 1980’s did little to discourage the anti-science crowd. Perhaps a lack of firsthand experience with the measles contributed in part to their anti-vaccine stance.  As I gazed into the mouth of a patient during the measles outbreak and saw a Koplik spot, a physical finding that indicates measles, I realized that the outdated knowledge of this physical finding I learned 10 years prior was not so archaic. Actually, I had simply forgotten about this pathognomonic signal of impending rubeola. “Out of sight,out of mind,” I said to myself.

Now, the COVID-19 pandemic has arrived and upended our lives as did the many infectious diseases of bygone years.  Initial roll-out efforts for mass testing, tracking and isolating has been less than adequate. We have finally resorted to social distancing, an ancient form of infection avoidance.  Clearly, the same weapons seen in the great mortality known as the Bubonic Plague during the 14th century. Ultimately, a vaccine will rescue us along with medical mitigation via drugs and antibody rich plasma from those who have recovered. Let us take the lessons of this catastrophic time and the stories from our heroes: the first responders, the healthcare team and informed public servants with us for centuries to come.  Otherwise, we sentence ourselves to repeat the same mistakes.

The following is an edited transcript of infectious agents seminar against human health, October, 2019:

Moderator: Thank you for taking the time out from afflicting disease to attend this seminar and welcome our latest pathogen in training, SARS-CoV-2. Viral agents and Rickettsia should take the first few rows that contain cell cultures. It is my pleasure to introduce our guest speaker,  inflicting misery on Homo sapiens for centuries, our President, Yersinia pestis.

Yersinia pestis: Thank you. For those of you who are unfamiliar with my resumé, I am responsible for bubonic, pneumonic and septic plague. Partnering with the black rat and rat flea, I have inflicted death rates of 50-80% for generations. I helped take down the Roman Empire in the 6th century by killing thousands of farmers.  Since the farmers were now not available to pay their Roman taxes to support the military, this led to the collapse of the Roman armies. My greatest hit was 1346-1353 where I took out half of the population of Europe. I started out in China, traveled with traders overland and with the shipping trade and went west, south and northwest, tightening the noose of misery on millions. I took on one of the greatest city-states at the time, Florence, and annihilated hundreds of thousands. For those Florentines that had a false sense of security and fled to the countryside, my coterie of fleas and bacilli followed them and finished them off. I rushed into Avignon, then the seat of the papacy, and inflicted so much suffering that the Pope blessed the Rhône River as a burial site. As the centuries passed and I lost some of my virulence, I came back every few generations of humans to remind them of my sordid deeds.

 Of course, I couldn’t do it alone so I’d like to introduce my fellow “partners in crime.”

Bacillus anthracis: Thank you, Yersinia. Some may say I take a backseat to the Plague but others recognize me as a formidable foe. I cause Anthrax. I received some kudos from human terrorists who used my spores to infect others through the U.S. mail in 2001. I am crafty and can infect humans through the skin, lungs and gut. Proudly,  I can kill 85% of victims within hours or days. What about those deaths in England in 1348-1349? Yes, I chipped in with Yersinia by killing cattle, transmitting my disease through eating meat and leaving my spores in burial graves. My spores can stay viable in soil for over 40 years! Now, THAT is staying power.

Moderator: We acknowledge the lesser known genera, Rickettsia and their contribution to human suffering.

Rickettsia prowazekii: I’ll be brief as I cannot stay long outside my cell culture medium. I may be intracellular but even humans acknowledge my clout: my disease is called EPIDEMIC typhus. My ride is the human louse, pediculus humanus corporis. I thrive with poverty, war and overcrowding and feel at home in endothelium, the cell that lines blood vessels. I cause rash, headache, cough, muscle pain and then progress to shock and delirium and then death. I have caused more deaths than all the wars combined. I was there during the Peloponnesian War in ancient Greece, the Thirty Years’ War and the Napoleonic Wars. In fact, I killed more of Napoleon’s troops than did the Russians. I caused misery and death during the Great Irish Potato Famine in 1846 and spread to England. The English called it the “Irish fever,” blaming the Irish instead of giving me full credit for the disease. While poverty and hygiene has improved recently and the human louse is in short supply, I jumped to the flying squirrel to cause intermittent disease in modern humans. Please be assured, I am still in the game and doing my part.

Moderator: My thanks to all of the innovative microbes that have stricken so many for so many centuries. Now, we welcome our latest entry to the world of human virulence,  an RNA virus from an unheralded family. Let’s give a warm welcome and a round of applause for SARS-CoV-2.

SARS-CoV-2:  I am humbled to take my place among the greats of infectious disease. I want to express my gratitude to our “think tank” and mammalian assistant, the bat, who has unselfishly provided incubation over the centuries to improve our infectivity.  I proudly come from the family of Coronaviruses. We have been in the human disease business for over 800 years, but have been underwhelming as we have only succeeded in causing the common cold with our first 4 family members. We showed promise in 2003 with the release of my brother, SARS-1, and a later cousin, MERS. SARS-1 had an encouraging mortality of 50% and we were packing the ICU’s in Asia. We did not plan for high transmission rates and with public health measures we were stymied early in the game. I inherited 85% of the genome and fine tuned my transmission rates. In contrast to my ancestor SARS-1, who was most infectious during severe illness, I made sure I could jump to another human even before they were experiencing my infective presence. This was the magic bullet for my success and I am honored to be nominated for rookie pathogen of the year.

Yersinia pestis: I want to thank all in participating in this important update. Let me remind you that Homo sapiens are adaptable and we must be vigilant. In Florence, after several generations of plague, they formed isolation hospitals, board of health administrators and invoked quarantining measures to restrict my spread. They finally got the tools to see some of us in 1683 (early microscope, van Leeuwenhoek). Our fellow microbes have been betraying us starting in the 20th century with penicillin (the mold Penicillium notatum), streptomycin (the bacteria Streptomyces griseus), and tetracycline (Streptomyces aureofaciens). Our machinery has been co-opted  (DNA polymerase) and our bacterial tools to prevent viral infections in us have been discovered (CRISPR technology). We can take solace in that humans have short memories and often make irrational choices and blame others that have nothing to do with their plight. But we must stay vigilant: It is never too late to mutate! Let me call this meeting adjourned and we all look forward to next year’s gathering.

Universal precaution implementation is, in an ideal world, best adopted in a slow, compliant fashion with a critical care or scrub nurse equivalent monitoring the provider for breaches in technique while putting on and removing personal protective equipment. In real life, emergent events require rushed donning of masks and gowns with possible gaps in the mechanical barriers. Of course, infective risks are greater with the lack of N95 respirators and the use of less protective surgical masks. Now, let’s look at the public risks of community exposure when the family equation is factored in. At least a dozen or more providers may enter an ICU bed in a given day. Most of the health care professionals are young, have families and extended families that they interface with on a daily basis. A four person household with a dozen personnel exposed to COVID-19 and a national number of 85,000 ICU beds creates a potential exponential source of infection in the community.

More masks, more providers and infrastructure are needed now. Can this be possible? Innovation in equipment, medical therapy and healthcare delivery are possible given the resiliency of Americans devoted to the well being of the United States. Is it possible? I have faith that this can be overcome. And, yes, my teenage patient  in 1979, after 30 more days in the ICU, walked out of the hospital with a smile on his face and his health intact.