When will COVID-19 end (in the US)? In 23 months or 8 months?
September 25, 2020 by Mona Ottum, MS, RDN, IFMCP, CLT, CD
“When will it end?” I can’t be the only one to ask this question or cry it out in the night. Life as we knew it stopped about mid-March in the US with full quarantine and social distancing in Michigan March 28. At this point, the US had already suffered 2,700 deaths due to COVID-19. There is no doubt that the old saying “we closed the barn doors after the horse got out” applies. Since the first confirmed US case on January 20, COVID-19 began spreading like wildfire.1
But here we are, me in Michigan watching the last beautiful days of summer trickle away and truthfully squeezing in as much outdoor adventure, camping, kayaking, biking and gardening, as I possibly can. But I miss the parties, weddings, BBQ’s and seeing my son in Colorado, throwing an appropriate soiree for my daughter’s medical school graduation and engagement. I miss my church friends, my choir so much. I “go to virtual church” twice a week thanks to a lovely church with enormous tech resources and effort to stay connected, but it’s not the same. And I could be characterized as somewhat of an introvert so I know social isolation is causing great suffering for many of you out there and my heart goes out to all of you.
So I asked myself, “When will it end?” then realized, we have enough information to have a good approximation of an answer. I am a scientist, engineer, dietitian with three college degrees who LOVES math. I research and do math for fun. But when there is an important question to answer, I go deep down the rabbit holes, like I do when I am researching how to get a client well. This is my nature and my instinct. When I got the answer, I realized that it was very helpful for me and thought I would share with you.
Herd immunity: When a certain percentage of a population has had an infection, or has been vaccinated, and is now (presumably) immune to re-infection, the likelihood of an infected individual passing to a vulnerable person becomes so low that the infection disappears. Many, many variables enter in to this number. These include how easily the infection transmits, how long it is transmissible, how concentrated a population is, how mobile it is and much more.
R0 is highly variable AND somewhat controllable: Note that the behavior of wearing masks and hand washing alter transmissibility and quarantine and social distancing alters mobility. So R0, or the scientists way of describing how easily an infection spreads, is highly variable, and to some degree, controllable. The point where R0 become 1.0 or below is where the infection dies out. Some places in the world instituted these actions early in the process and managed to almost stop the spread of the virus entirely. But if you institute social measures too late and inconsistently, and to be fair, only 2 or 3 weeks too late is all it takes, herd immunity is all we have to bring an end to the spread of this virus and our social isolation.
So back to herd immunity, 43%! At this point, we want to know what level provides herd immunity under “normal mobility” of travel, gathering, parties, shouting at sporting events and singing at church, all the things we miss and love. We want to know when we can hug our friends and family and gather for celebrations. I want to know when I can cook for loved ones, friends and clients (I LOVE doing cooking classes!). The experts have been saying that herd immunity for COVID-19 is between 60% and 70% of the total population. But a later model has put herd immunity 43%.2 This new model considered the variable of “social activity”. In essence, some people in a population are more socially isolated by their very nature. So I went with 43% because this is the latest and best number and I am an eternal optimist and excited by this lower estimate. But don’t get too excited. Here is how many people must have either 1. Recovered from the infection 2. Been vaccinated.
Current US population: 328,200,000 X 0.43 = ~141,000,000 must have immunity
How close are we to herd immunity? The true infection fatality rate or IFR from “community sampling” can tell us: The percent of people who have actually gotten the infection in a population and died has been an elusive number, not because we do not know who died as a consequence of COVID-19 (contrary to popular belief, a conversation for another day), but because we don’t know how many people have been infected but did not die. This is due to several important factors. First, many, MANY, people get COVID-19 and do not get sick or only get mildly sick. Second, we have only had reliable testing for active infection or post-infection antibodies for a limited time and in limited numbers. Third, in the setting of limited resources, we are primarily only testing those with symptoms or exposures. Here is where research and science has had time to fill the blanks with what is called “community sampling”. Several studies have been done around the world where a representative and broad sampling of a particular community tests people regardless of exposure, symptoms or risk. A systematic review and meta-analysis of these studies (pre-publication) have found a couple of very important things.3
- The actual infection fatality rate (IFR) is about 0.68% (0.53 to 0.82%).
- The actual infection level is 4 to 11 times the number testing positive and reported, depending on how broadly or narrowly testing is done.
We can estimate how many people in the US were infected cumulatively three weeks ago by how many total death we have today (there is a 3 week delay between infection and death). So three weeks ago (from 9/25/2020):
201,411 Deaths today / 0.0068 = ~30,000,000 Infections in US
Cumulative infections reported 3 weeks ago in US: 6,189,815
How many people in the US who had COVID-19 but were untested and missed?
30,000,000 / 6,181,474 = 4.9 or
- The actual infection rate is currently 5 times that reported
- For every infection detected, there are 4 that are undetected/unreported
Yay! We are a lot closer to herd immunity than we thought, right? Closer, yes. Close, no. Remember:
Number of survivors/vaccinated needed in US for herd immunity: 141,000,000
Number of current survivors/vaccinated in US: ~30,000,000
At 7 months into the pandemic, we are 19% of the way to herd immunity.
30MM / 141MM = 21%
At the current rate, when do we reach “natural” herd immunity? If we move to herd immunity “naturally” meaning without a vaccine, we would achieve herd immunity when we hit 141MM survivors. The current death rate is about 1100/day so this is about 5MM infections per month. With both school and winter approaching, we might rip the Band-Aid off and get it over faster with another bigger spike, but for now I’ll assume that it is stable.
141MM – 30MM = 111MM more infections / 5MM infections per month =
22 more months.
Herd immunity for COVID-19 would be achieved naturally in ~22 months or…
Natural Herd Immunity: August 2022, 2 years from now
How many deaths will result from COVID-19 at that point, a total of 30 months in:
141MM X 0.0068 = 958,800 COVID-19 deaths in US or ~1MM
What if we vaccinate? I cannot lie. I am a functional health practitioner and conservative with conventional medical interventions with respect to preventable and reversible chronic illness. I am not a fan of universal vaccinations and the heavy rapid load we do to our infants. I have seen the consequences of adverse reactions to vaccines. I have also enjoyed the benefits of vaccines that have eradicated horrible diseases like polio and tetanus (not without some serious early mistakes). But can I live 2 more years of this and 1MM deaths? Can we? We are stuck with the current situation, plodding along as small businesses and mental health circle the drain until a major event disrupts the process. Two major events can speed things up.
1. A second wave as a result of going back to school and partial opening of society and perhaps a third wave coinciding with the flu season and indoor confinement.
2. An effective vaccine.
Vaccines on the fast track are at least 4 months away and their impact 6 months away. The most aggressive projections are for vaccines to be tested, manufactured and available for distribution by the 1st anniversary of the arrival of COVID-19 on our shores, about February 1, 2021. Assuming an effective and safe vaccine is available, the process of getting at-risk and priority people vaccinated and then the 3 weeks for people to actually mount an immunity is at least 2 more months. That is 6 more months on our current trajectory. Where will we be at that point (April 1, 2021)?
Current deaths 201,411 + (6 months X ~33,000 deaths/mo) = ~400,000 deaths
Lives saved if we vaccinate in winter 2021:
Months sooner returning to “normal” life with travel, concerts, sporting events and church if we vaccinate in winter 2021:
Decisions, Behaviors, Choices and Beliefs: Here is where I depart from the science and share my heart. The United States is a collection of the most educated, creative, resourceful, diverse and resilient people on the planet. I believe that we can collectively get through the next 7 months without unnecessary excess loss of life. But to do this, we have to be more. We have to be more patient, kind, compassionate and compliant with wearing masks and social distancing where required. We have to have more faith in science and medicine as it fulfills its original and pure purpose, to ease suffering and save lives. We owe it to ourselves to find ways to experience and give love, joy and grace along the way. If you put others first for 8 more months, you give yourself back your normal life 15 months sooner with COVID-19 vaccines. Together, we can make the next 8 months our best.
As for me, knowing that the most vulnerable to COVID-19 are underserved and those with chronic illnesses, my focus on restoring health with functional medicine will continue with more conviction than ever. Preventing deaths is always better than counting deaths but the journey out of chronic illness is not fast and easy and for many with socioeconomic limitations, not even realistic in this short term. In the short term, vaccinating to save lives while continuing to fix the systemic broken food supply and health disparities that amplifies chronic illness is the pragmatic and compassionate approach. In the long term, functional medicine, and I, will not only be working to help people be more resistant to such infections in the future, with vitamin D and other inflammation reducing strategies, but helping people fully recover from the lingering effects of the virus.
(1) (See https://en.wikipedia.org/wiki/Timeline_of_the_COVID-19_pandemic_in_the_United_States for a detailed timeline if you are curious or prone to mistrust and believe conspiracies)
(2) Tom Britton, Frank Ball, Pieter Trapman. A mathematical model reveals the influence of population heterogeneity on herd immunity to SARS-CoV-2. Science. 2020 Jun 23 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7331793/
(3) Gideon Meyerowitz-Katz, Lea Merone. A systematic review and meta-analysis of published research data on COVID-19 infection-fatality rates. Posted July 07, 2020. https://www.medrxiv.org/content/10.1101/2020.05.03.20089854v4