A guest post written by my beloved husband….

Originally posted on March 16, 2020; updated on March 19, 2020

Avoiding COVID‐19

We are witnessing a rapidly evolving pandemic, that is unpleasantly similar to the plagues of the past, and more like science fiction than the reality we took for granted. In many ways COVID‐19 most resembles the Spanish flu from 100 years ago: it’s mortality rate (currently 3.8% vs 2%), it’s R0 (R-naught = contagiousness; currently 3.1 vs 2.0), and its rapid spread across the world. The Spanish Flu of 1918 killed 650,000 americans and >50 million people worldwide. COVID‐19 is related to two other coronaviruses, SARS and MERS. Like them, it is a biosafety level 3 (BSL‐3) pathogen, that’s now loose and uncontained in the population.

Even a few days ago I heard people minimizing or dismissing the severity of this situation. But, as it became known that 12,000 new cases arose in Italy in the past 48 h, and 370 people died yesterday (Italy has a mortality rate of 7.3 %), that unrealistic viewpoint was replaced by fear and panic. No vaccines or anti‐viral medications exist for MERS, SARS or COVID‐19, so we cannot expect medical intervention to stop the pandemic in the near future. The best person to listen to for advice on how to guard against coronavirus is Dr. Anthony Fauci, Director of the National Institute of Allergy and Infectious Diseases. He is one of the world’s foremost experts on viral pathogens. Still, I read an article asking for guidance on how to avoid contracting COVID‐19, and so I’m summarizing some practical advice about that. You may not need this input, but I want to provide it in case anyone wants it. My wife Sally and I were trained by excellent microbiologists, from whom we learned procedures that prevent contamination. We use them in our laboratory, and as we watched COVID‐19 progress over the past weeks we made a plan to adapt these methods for our home. We are in a high‐risk group, but with this approach we hope to avoid contracting the virus. Given its very contagious nature, that’s a tall order. What follows below is a step‐by‐step plan for how to change life at home.

1. Prepare disinfectants.Coronaviruses are microscopic particles, invisible to the naked eye, that have an RNA genome within a lipid bilayer membrane that also contains proteins. The membrane makes the virus hardy and protects it outside the host cell.   However, most viruses, including COVID‐19, are susceptible to destruction by bleach or alcohol. The first thing to do at home is to prepare two types of spray bottles, one containing 10% bleach, and one containing 70% alcohol (either isopropanol or ethyl alcohol). If you are not knowledgeable about making such solutions, here’s how to do it. For the bleach solution, mix 1 part CLOROX with 9 parts water. Do not use cheap, off brands of bleach; CHLOROX contains stabilizers that maintain its potency for up to 5 days after dilution in water.  Ordinary bleach loses efficacy within 1 day of dilution in water.  For the 70% alcohol, you can buy bottles of 70% isopropanol in supermarkets or pharmacies. You can also buy EVERCLEAR (it is 95% ethyl alcohol) in a liquor store, and mix 3 parts EVERCLEAR with 1 part water. Isopropanol is also available as a 95% solution, so you can dilute that the same way.  10% bleach, 70% isopropanol or 70% ethyl alcohol inactivate and kill COVID‐19 within a minute of exposure. Put these solutions in 1 qt spray bottles (available at supermarkets, pharmacies and hardware stores) for general use. We also prepare small, 60 mL spray bottles of 70% alcohol to carry in a pocket or purse, and use them to spray down anything that we suspect might be contaminated, including our hands, shopping cart handles, door knobs, gas pump dispensers, etc. You can find these small spray bottles in pharmacies or eye centers, because they are often used to hold eyeglass cleaning solution. Don’t skimp when decontaminating something with bleach or alcohol: give it a thorough coating, until it’s wet with the liquid, then let it sit for at least a minute.

2. Eliminate hand‐to‐mouth contact.When you are in a potentially contaminated environment, whether it’s a public place (grocery store, office, classroom) or in your home, it’s crucial to avoid touching your face. That’s the first priority in the laboratory, but it’s not easy to remember or accomplish. One tip that helps is to think about keeping your hands below the level of your shoulders. If you don’t raise your hands above your shoulders, then you cannot touch your face. Second, maintain a discreet distance from other people, a few feet away. Coronaviruses are quite hardy.  Recent findings (Mar. 17, New England Journal of Medicine) describe the survival of  COVID-19 (also called SARS-Cov-2)  and the related SARS (also called SARS-Cov-1), in the air and on different surfaces: in the air, 3-4 h;  on cardboard, 24 h; on copper, 4 h; on plastic or stainless steel, 2-4 d. Respiratory viruses are present in fluids from the lungs of infected people, but coronaviruses are not airborne… that is, they don’t fly. When they are coughed or sneezed or breathed out in the respiratory droplets of sick people, they have a maximum range of projection of a few feet, before the droplets fall to the floor, a table, or a countertop.  Hence, keep your distance (6 ft) from other people, but especially from anyone who has symptoms of sickness.  A sick person may contaminate others by coughing or sneezing or talking, any of which can project droplets of the virus. But, those droplets fall out of the air in a few minutes, limiting the scope of direct contagion.  On the other hand, a sick person walking through a room touching things leaves a trail of millions of viral particles, that in the case of COVID-19 remain viable and infectious for days.  The head of a pin is large enough to hold 70 million virus particles.  If a sick person walks through a supermarket, even without directly encountering anyone, his or her hands will likely contaminate the shopping cart, that may infect the unlucky 10 – 15 people per day that use it over the next few days, by hand-to-mouth.  Consequently, and perhaps most important, healthy people become infected by touching a contaminated surface, and then touching a mucous membrane (eyes, mouth, nose) without decontaminating their hands.  But, the virus cannot penetrate unbroken skin, so if even you touch an infected surface you can wash your hands or sterilize them with 70% alcohol or 10% bleach to protect yourself. Make a habit of washing your hands with warm soapy water, and when you are out and away from a sink use 70% alcohol to sterilize them.

3. Re‐organize the home environment.At present our city and the university are free of coronavirus, but that will soon change. Now is the time to prepare for a situation in which a percentage of residents are carrying COVID‐19. Yesterday 14% of 1500 people tested in New Rochelle, NY were carrying the virus. Soon, whenever we leave our homes, we will venture into a potentially infectious situation. Besides the possibility of direct contamination, the foods and other items that we bring home are a risk, because they are prepared, packed and shelved by people who we know nothing about, who might be infected or sick with COVID‐19. The mushrooms and broccoli that we cooked last night were from Watsonville and Soledad CA, respectively; today CA reports that 400 of its residents are infected.  At its current growth rate, in a week that number, which is probably a gross underestimate, will rise to >3000. California is just an example; many places that we obtain food and merchandise from have similar levels of infection. Unfortunately, within days or a week people here in town will be infected too. The bottom line is to make your home a sanctuary from any threat of infection by COVID‐19. To do so, we decontaminate things that come into our home. At present these precautions may seem extreme, but we are facing a potentially lethal virus that is unprecedented in recent history. The decisions that we make and the actions that we take are literally life‐and‐death choices. Why take chances with the lives of loved ones?

a. We installed a table in our garage, on which we spray potentially contaminated things with bleach or alcohol, before they enter our home. Most of our foods are packed in plastics anyway, so it’s easy to spray them down. Use your best judgment about what needs decontamination, but anything that was handled by several people should be either cleaned or well‐cooked. Assume that the exterior of anything you purchase might carry particles of live virus.  When shopping, try to use your credit card instead of cash or coins, and spray it with alcohol before putting it back in your wallet.  When you return home from shopping or other errands, leave your shoes in the garage and put on some shoes that never leave the house.

b. Besides the garage, divide your home into different areas, for: incoming unpacking/triage/decontamination, cooking, eating. We have a space in the kitchen to place incoming stuff that we are unsure about. Do not place incoming bags of groceries, packages or mail directly on the countertops used for food preparation. Decontaminate the contents first, and then start cooking. It’s unlikely that COVID-19 will survive during transit in the mail because its survival is much shorter on porous surfaces.  Nevertheless, the people that handled the mail during delivery might be infected, so after opening mail discard the envelopes and packaging and wash your hands.  After shopping, wash and decontaminate your hands, and then unpack, decontaminate and store your items.  Throw the bags away in the trash.  You can spray or soak fresh produce that you want to eat raw (celery, carrots, lettuce, broccoli peppers, etc.) with a dilute solution  of (unscented) CHLOROX (0.75% = 1.5 ts per gallon of water); let it stand for at least 5 min and rinse with water before eating.   After unloading, decontaminating and storing everything, wash your hands again before food preparation.

c. De‐clutter and organize the countertops and tables in your kitchen. To keep your kitchen safe, it’s necessary to frequently and easily clean all these surfaces with bleach or alcohol. Throw away anything unnecessary, store anything decorative, put away everything not in use, and keep counters and the sink clear. In the morning, before cooking, and in the evening before bed, spray the countertops, eating areas and sinks with 10% CLOROX and wipe them down with a clean cloth.  You may want to wipe the countertops with alcohol before using them during the day.

d. Carry a small spray bottle of 70% alcohol in your pocket or purse, and use it to decontaminate anything you are skeptical about: your hands, your steering wheel, your door handles, your computer keyboard, your phone, your keys, shopping cart handles, touchscreens. Liquid/gel hand sanitizers also contain 60‐70% alcohol and they work fine, but they are less penetrating than an alcohol spray, and more difficult to apply to surfaces. 70% alcohol will not damage glass, plastic, metals or your skin. It will dry your skin, so it’s a good idea to also use hand creams to re‐moisturize.

e. Change your clothes regularly and do not re‐wear clothes that you wore outside without washing them. When you leave your home you are entering environments that might contain COVID‐19, and it could get on you clothes when you are working in an office or sitting in a chair. When in doubt, wash it. If you can’t wash it, then hang it in a closet for a week. COVID‐19 does not survive as long on porous surface like fabrics.

f. Don’t go to restaurants, bars, clubs, churches, theaters or any other place where people congregate. Do not invite other people into your home.  Do not go to health clubs or gyms.  Try to do as much as possible electronically from home with your computer or phone. Avoid trips outside the home; shop as infrequently as possible. The next few months will be critical in the fight against this organism. It’s a good time to stay home with the family, to write, read, stream entertainment, watch the news and listen to Dr. Fauci. If you follow these approaches it will maximize the chance of avoiding sickness from the coronavirus.

Additional notes on Mar. 19, 2020

Without a vaccine or an effective anti-viral drug, the only approach left to stop the pandemic is to eliminate person-to-person transmission.  China’s response of complete, militarily enforced quarantine in Hubei province leveled off the incidence and the mortality of the epidemic within 2 months, at a total of 3200 deaths (only 34 new cases, and no deaths reported yesterday).  South Korea took a similar approach.  As a result, the number of new cases in these countries plummeted, and the infection is under control (see the graph below, from today’s New York Times).  Looking at the responses of Italy, Iran, Spain and the US, all of which initially did nothing to contain it, the results are strikingly different: exponential growth of the virus and exponential death of infected individuals, neither of which shows any indication of subsiding.


The bottom line is that many, many people are going to die from this pandemic, and the only thing we can do, until vaccines or treatments are available, is to stop transmitting it person-to-person.

P.E. Klebba, Ph.D