I fear the authorities who claim to know best have made a terrible mistake. In the absence of an effective vaccine (or any vaccine at all) for SARS-CoV-2, they have prevented the population from developing widespread immunity to the virus, what we call “herd immunity” (or “herd protection”). Since this virus is now part of the seasonal mix (that’s right, it’s not going away), this means that the same situation experienced this spring will be re-experienced in the future. If we had to lockdown on account of this virus this time, that is, if the lockdown were necessary, then we will have to lockdown again next time. But we won’t. This suggests that not only was the lockdown unnecessary, but that the whole exercise was counterproductive to the ends of reducing future outbreaks of the virus. A lot of hope is being placed on finding an effective vaccine in record time.
What is “herd immunity”? When an infectious agent enters a population that has no immunity to it, it spreads very quickly. One person can infect many people. Each newly infected people in turn infects more people. And so on. This is called “community spread.” If a sizable proportion of the population is immune to the agent, a limited number of spreaders will in turn slow the spread. For example, if 80% of a population is immune to a virus, only one out of every five persons may contract and spread the virus (exposure does not necessarily mean infection). Without 100% of a population enjoying immunity from the agent, some persons may still contract and spread the virus, but 80% herd immunity means fewer outbreaks of the virus and the virus may be effectively contained. It is generally accepted that between 70% and 90% is a high degree of herd immunity.
There are two ways to achieve immunity to a virus. The first way is to contract the virus and survive it. If a large enough number of persons get the virus and survive, the population will have achieved some degree of herd immunity. The second way to achieve immunity to a virus is an effective vaccine. For example, presently, the efficacy of the seasonal flu vaccine is around 35-40%. Others have immunity from acquiring the flu in previous seasons. The flu is still widespread. Many people get sick from it. And some will die from it. But many people won’t get sick from it thanks to their own immunity and to the immunity of others. So even with lower levels of herd immunity, the detrimental mass effects of a virus are mitigated.
Keep in mind that some viruses are more stable than other viruses. DNA viruses, such as chickenpox (varicella), mutate rather slowly. One may acquire life-time immunity after contracting and surviving a DNA virus. RNA viruses, such as influenza, mutate more rapidly. Exposure provides time-limited protection. However, not all RNA viruses mutate as quickly as others and exposure to any strain may provide some protection to mutants of that strain. This is why the flu vaccine has limited efficacy in providing herd immunity and becomes less effective over time while, at the same time, those who acquired a flu strain in years past may have immunity for this strain in future flu seasons. For example, the Hong Kong flu, influenza A (H3N2), while devastating during the 1968-1969 flu season, continues to circulate without the accompanying devastation. Many of us who lived through that virus, however much our immunity to it is diminishing over time with the mutation of the virus, acquired some degree of immunity to the Hong Kong flu. Moreover, re-exposure to the virus boosts our immunity response as our bodies learn to recognize variations on the original pathogen.
And this brings us the problem of the response of many governments to the SARS-CoV-2 virus. The world population is 7.8 billion people. The number of confirmed cases of the virus is 1.9 million. Of those confirmed cases, 121,987 have died. That leaves 1.8 million who, if they all survive, with possible immunity. That’s 0.023 percent of the world population. In the United States, which has been hit harder by this virus than most countries, with 328.2 million people, and 563,820 confirmed cases (after subtracting deaths), the percent with possible immunity is 0.17 percent. That is obviously far below the levels we need to manage future outbreaks of COVID-19, the disease caused by SARS-CoV-2.
We know that most people who get the virus are asymptomatic (they are exposed and produce antibodies but do not develop the disease COVID-19) or have only mild symptoms. The evidence suggests that this accounts for eight out of every ten persons. Most of those persons are not tested. Moreover, there are some with severe symptoms, that is, those who experience a flu-like illness, who are also not tested. They recover without medical intervention. Let’s suppose that there is ten times the number of confirmed cases in the population who will become infected and acquire immunity. That takes us to 1.17 percent herd immunity, still far below what is needed to limit future outbreaks.
In other words, the lockdown has prevented the achievement of anything close to a desirable level of herd immunity. It seems to me that the smart thing would have been to identify those who were at special risk from the virus and protect them while allowing the virus to burn through the world population. This would have relegated the virus to the common viral mix the human population endures every year without calamity.
One argument for the lockdown wasn’t so much to prevent people from getting the SARS-CoV-2 virus per se, but to prevent the spread of SARS-CoV-2 to save hospitals from being overwhelmed by COVID-19 cases. While this seems reasonable, and many are lauding the lockdown’s accomplishment over against the apocalyptic predictions, getting through the current period with a limited number of infections, represents a pyrrhic victory. Politicians and pundits love the war metaphors, so while we will have won the battle, we are facing much greater loses in the next season of war, which will cover many more months than the period encompassing the present pandemic. The question we should be asking of the official rational is why weren’t hospitals prepared to deal with COVID-19? But this is aside from the question raised by this essay. Or, perhaps, I might put it this way to bring this into consideration: why did we sacrifice acquiring herd immunity for the sake of the failure of the medical-industrial complex?