Deconstructing an Epidemic

Epidemic infections are driven by human behavior and define our species.

Posted Feb 21, 2020

wikimedia commons
The Plague of Athens 1652-1654
Source: wikimedia commons

The first international reports of #COVID19 began filtering through in mid-January 2020…a doctor in China warning others of a new, lethal, highly infectious virus in Wuhan. News reports followed, from official sources, first case December 31st, neighborhoods swiftly in lockdown and quarantine measures. The internet started to pass through alarming videos reportedly from China…people passing out in the streets, doctors crying and pleading from hospitals. The whistleblower doctor, only 34, dies from the infection. Conspiracy theories run rampant…it was a manufactured virus that escaped from the Level 4 lab in Wuhan (debunked), the first case was actually December 6th (debunked)…no, Patient Zero came to the hospital on December 1st, an elderly man with dementia.

I can tell you with high certainty that Patient Zero was not the first. Who am I? My bonafides are scant: a B.S. in Biology, an M.D., and by a quirk of fate, a long history of science communication on the Internet. I’m not a virologist, or an epidemiologist, or an infectious disease specialist.

That said, a psychiatrist can understand some things about the human condition that resonate beyond the cold hard calculation of infective potential and case fatality ratio: about epidemics, the human spirit, and the evolutionary past or our species.

Patient Zero is an imagined construct at this point. It was the named Patient Zero’s son-in-law’s brother whose girlfriend stood on a bridge at night, holding onto the railing, not noticing a sickly bat was drooling there moments earlier. She pulls out a cigarette and plops it in her mouth. It happens. My dog sometimes breaks through and licks my face sometimes. We touch our faces, we bite our nails, we pick our noses and rub our eyes. All are fine opportunities for infection in the wrong place at the wrong time.

She was asymptomatic, but she made out with her boyfriend, who caught a cold (it’s wintertime), who went to a family outing…there are a million scenarios here. The 2011 movie Contagion, where Gwyneth Paltrow’s exposure leads to the death of millions, has a plausible disease vector from animals to humans.

Epidemics start with a mutant cold, a pangolin who is poorly and sneezes in your face. They continue through normal sweaty nose-picking human activities, and get fenced in with heroism or fanned ablaze with denial and recklessness. We’ve seen more the latter than the former this time around.

Human populations are marked by epidemics. Cystic fibrosis carriers, quite common in Caucasian populations, are more immune to tuberculosis. Sickle cell carriers in African-derived populations are more immune to malaria. There are questions about vulnerability to psychiatric diagnoses…does a greater immunity to infectious diarrhea as a kid leave us more vulnerable to developing depression as an adult? Our ancestors survived many epidemics in the past, but only recently have we been so vulnerable to a global pandemic.

There are four endemic coronaviruses that circulate the world population, causing the common cold. Most of us had them all as children and experience lighter and shorter infections later if exposed. We endure them, go to work, sniffle, and cough, and don’t think much of them.

Two others came out recently, SARS and MERS, both not as infectious but much more deadly. Their deadliness seems to have snuffed them out, with short incubations and virulent symptoms that incapacitate.

But this new virus has a diabolical combination of a long incubation period, high infectious potential, and mild symptoms at first. The final case fatality ratio is unknown. It’s less than SARS (10 percent) or MERS (30 percent?); probably around 1 percent. It could have been worse, but in general, the less deadly a virus is, the easier it is to spread to everyone. It seems to spare children and be much harder on the elderly. It is our next pandemic.

A pandemic is a new infectious disease that has worldwide spread. We have no special innate immunity. The only relief is antivirals, vaccines, or not being exposed (masks, handwashing, personal protective equipment used appropriately in near contacts and health care professionals). We can slow it down with quarantine, but unless the people quarantined are too sick or the quarantine is short or brutally enforced, it is inevitably violated and the infection spreads.

Humans evolved big brains and a high potential for denial. I may be sniffling but it’s just the usual cold…I’m not going to be trapped here behind these barriers locking in my neighbors. It’s been 12 days in quarantine, I’m sure I’m fine.

This brings me to masks. Aerosol respiratory droplets can be tiny and fly for several meters. Wearing a standard surgical mask to stop these is like using a soccer net to catch a fly. N95 “respirator” masks squeezed uncomfortably across your nose will help, but we don’t have an unlimited supply, and should be preserved for health care workers, the elderly, immunocompromised, and close contacts of infected people. A standard surgical mask *will* help protect others if you are sick and coughing or sneezing and decide to go out in public. An average healthy person in the U.S. should focus on hand washing and trying not to touch your face unless you’ve recently washed your hands; the same as seasonal flu precautions. (Since writing this article a month ago I have changed my mind on this position, read my new post to see why.)

What is going to happen in the U.S. in the coming days and weeks? Here’s a prediction as of February 21st, 2020 at 6 p.m. Eastern time. Your immediate danger is almost zero. If we are lucky, 1/3 of the cases coming from China were caught and quarantined. The average incubation period of #SARSCov2 is 5 days, as long as 14 days…the early tests aren’t 100 percent either. After that, one has a week of mild symptoms, then perhaps a sneezy, coughing cold. In week three, you recover or you (typically the immunocompromised or elderly) die.

By the numbers, 16 cases are confirmed in the U.S. as of today, most in travelers from China. So at least 30 slipped through, and are out there, waiting for one person to have a mild cold and go to work in the kitchens at a nursing home and infect everyone. Or one parent of a toddler to pass her cold to the little munchkin, whose runny nose is hardly unusual, to all her friends, their parents, their grandparents, etc. 

It’s 5-14 days plus a week or two to infect a few more people per case. Some infect none; others more. There’s no obvious difference in most people between the seasonal colds and flus we deal with every year. My household had three of four struck down with fevers this week…we recovered in a few days, it’s viral, nothing you can do. Nothing out of the ordinary — stay at home, cover your mouth when you sneeze, and rest.

But #SARSCov2 is far deadlier than your common cold and probably more than the seasonal flu. Thirty cases becomes 90, and then there’s a death from atypical pneumonia that doesn’t get screened in and recognized later in late February, and finally there’s a cluster at a church or a nursing home or a conference.

The real Patient Zero in Wuhan was probably in late October…it took a dense population in the dead of winter with poor air quality and high smoking rates to spread it super fast to epidemic levels by the end of December. The U.S. will be more smoldering in taking up the spark, began probably in late December…give it a few more weeks, a month, but it will grow. You can’t shovel enough sand to hold back the tide forever, not with so many people, so many mild infections, the human nature of denial, the dark influence of politics, and a long incubation period.

My advice? Wash your hands. Put aside a few weeks of food, toiletries, over the counter medicines. Get a 90-day supply of prescriptions if it is appropriate. This is not the end of the world, but double or triple a normal flu season will stress hospitals and could be devastating to nursing homes, inpatient psychiatric wards, and prisons and other institutions.

Ask for your doctor’s advice if you are elderly or immunocompromised. Healthcare workers should brush up on infection control procedures and doffing personal protective gear. Consider delaying that cruise booking to Southeast Asia. I know it’s hard — you are a good worker and productive — but stay home if you get sick in the next several months, even if it seems like a normal cold.

Epidemics happen. They are part of the human condition. We evolve more slowly than our microbe neighbors, but we’re also smarter, and can change our behaviors, and be safe.

Copyright Emily Deans M.D.