Putting Covid-19 Behind Us 

By Paul E. Lemanski, MD, MS, FACP

In my first nine articles on Covid-19, lifestyle-based risk mitigation strategies (including masking, social distancing, hand washing, targeted quarantine, and when necessary, lock downs) were recommended to keep the population well until a safe and effective vaccine was developed and “in the arms” of 85% of Americans. In this way, SARS-CoV-2 vaccination would help achieve so called “herd immunity” (see Non-Medicated Life, February 2021) and stop the transmission of the virus to those who were not vaccinated. Unfortunately, despite our having a safe and effective vaccine, many individuals for a variety of reasons have refused vaccination (see Non-Medicated Life, August 2021). 

This, along with a greater number of deaths from Covid-19 this year as compared to last, has led to the federal government to mandate vaccination for all employees or risk loss of job for refusal. Vendors that do business with the federal government have been forced to follow suit and have mandated vaccination of employees or risk loss of job for refusal. Some state governments and city governments have also mandated vaccination or risk loss of job for refusal. While such mandates have increased vaccination rates, they have also generated both controversy and potentially dangerous situations with significant portions of essential workers such as police, firefighters, nurses, paramedics, and hospital workers – all already in short supply – facing layoffs as a consequence. Is there a more nuanced way to reach herd immunity that respects the individual and avoids creating new problems? I believe there is.

Almost 45-million Americans have naturally contracted Covid-19 and survived. This represents a large proportion of the population that is not currently counted as vaccinated, who actually have been immunized by natural infection. Some of these individuals, at significant risk to themselves, became infected because they refused the vaccine. Others were vaccinated but contracted Covid because no vaccine is perfect and 5% of the vaccinated were expected to get Covid (although severe disease and death were avoided for the great majority in this group). There is evidence that those who have naturally contracted Covid and survive will benefit further from at least one dose of the Pfizer or Moderna vaccine. However, to mandate that these individuals all receive two doses of vaccine may be unnecessary to effective herd immunity.

Current research suggests that one month after symptom onset, 98% of individuals who recovered from a natural infection of SARS-CoV-2 had antibodies to the spike protein, which the virus uses to enter cells. Moreover, antibody levels were well-maintained over time, declining only modestly eight months after infection. Additionally, other measures of immune response were maintained. For example, B cells specific to SARS-CoV-2 increased over several months, then plateaued and were maintained for the eight months of the study. Six months after symptom onset, 92% of participants had CD4+ T cells that recognized SARS-CoV-2, and 50% had CD8+ T cells that attack other cells infected by the virus. In all, eight months after symptom onset from a naturally acquired SARS-CoV-2 infection, 95% of individuals had three out of five immune system response measures, indicating active memory of the virus and ability to respond to stop reinfection.

While it seems clear that those who have survived a natural infection with SARS-CoV-2 garner additional benefit after vaccination, those with a documented natural infection from the virus (both initial PCR nasal test positive and subsequent proof of SARS-CoV-2 antibodies in the blood) should be counted as naturally immune – at least, provisionally. In my opinion, while these individuals should be encouraged to be vaccinated, they should not be mandated to do so or risk loss of job. While the current antibody blood test is qualitative – meaning, yes, you have antibodies, or not – a better test would be quantitative. 

Such a quantitative test is available for SARS-CoV-2 (as used in research study cited above). It is similar to blood tests currently used to prove immunity with other viruses, for example, measles, mumps and rubella. The problem is we have no truly long-term data for SARS-CoV-2 – like we do with those other viruses – that natural immunity is long lasting. But we also do not have long-term data on the persistence of SARS-CoV-2 vaccine immunity, either. On this basis, to mandate vaccination or risk loss of job may seem unfair and potentially dangerous. While there is danger for the community if folks refuse to vaccinate, a different type of danger exists if we lose essential service providers from the workforce that are needed for safety and economic security.

Would it not be more fair and less disruptive for FDA, CDC, and state health departments to approve commercially available quantitative SARS-CoV-2 antibody tests to provide evidence of ongoing immunity, in both the population that is immune through vaccination as well as the population that is immune through natural infection? In the meantime, pending the approval of such testing, periodic qualitative antibody blood tests as well as weekly nasal PCR tests may suffice. Those who refuse vaccination, qualitative antibody blood tests and weekly PCR testing could legitimately risk loss of job. However, this numerically smaller group – if choosing job loss – may disrupt the delivery of essential services less severely.

In summary, to end the pandemic of Covid-19 requires the achievement of herd immunity in our population. Herd immunity is achieved when 85% or greater of individuals in the population have antibodies to SARS-CoV-2 in their blood, either by vaccination or natural infection. Mandates that threaten loss of job without vaccination have been instituted that do not recognize the immunity of natural infection. Evidence suggests SARS-CoV-2, if survived, may produce an immunity as robust and protective of reinfection as vaccination. Employing quantitative antibody testing for SARS-CoV-2 may document immunity, respect the individual, and avoid unnecessary job layoffs in essential workers.

Paul E. Lemanski, MD, MS, FACP is a board-certified internist practicing internal medicine and lifestyle medicine in Albany (centerforpreventivemedicine.com). Paul has a master’s degree in human nutrition, he’s an assistant clinical professor of medicine at Albany Medical College, and a fellow of the American College of Physicians.