There is no doubt that COVID-19 vaccines are working beautifully to drive down COVID-19 cases in the USA. With 170M Americans or 51% having had at least one dose of the vaccine, cases in the USA have dropped to a 14-mo low of 5 per 100,000.
However, there is a significant subpopulation of the USA, 10M or 3%, who may not be fully protected by the vaccines. These include those (>6M) that are taking immunosuppressive drugs such as steroids used to treat organ transplants, cancers, or other medical conditions, and those who have compromised immune systems due to blood cancers and other diseases. The original clinical trials for vaccines specifically excluded people who were taking immunosuppressive drugs to get their impressive 95% efficacy results. Real-life studies were equally impressive since less than 3% of those sampled were immunocompromised. More targeted real-life studies with immunocompromised patients show more disappointing results. One JHU study of implant patients showed 46% had no antibodies after being fully vaccinated. Another study from Israel showed that only 40% of all CLL cancer patients produced any antibodies after being fully vaccinated.
There are no public databases that track the large scale response of the immunocompromised to vaccines but it is well known that a higher percentage of seniors, increasing with age, are immunocompromised compared to younger adults. We suspect that this is one of the reasons why even though senior compliance with vaccinations is very high (86% of everyone over 65yrs in the USA have had at least one dose) seniors continue to get infected and die from COVID-19. In Florida (FL), the relative infection rate for seniors after falling to a low in April with the success of the Seniors First program is now close to what they were before mass vaccinations began in January, even though a much higher percentage of seniors (88%) have now been vaccinated than the general population (49%). As more of the rest of the population gets vaccinated this relative contagiousness for seniors may rise further. The optimistic view is that even for those who have no detectable levels of antibodies from B-cells, other parts of the body’s immune system such as T-cells have been trained after vaccination to fight SARS-CoV-2. This would be unlikely if the trend we see for seniors in FL continues to worsen.
What is the solution for this vulnerable part of the population who already have a much higher risk for hospitalization and death due to SARS-CoV-2 and who now seem to gain less from excellent vaccines? Some people have proposed a third vaccine dose and have seen some success with it. Others have proposed stopping immunosuppressants temporarily to allow the vaccine to do its work at generating antibodies. Others have proposed using monoclonal antibodies such as REG-COV as prophylactic. In the meantime the CDC’s new mask guidance does not apply to this vulnerable group who must continue to mask, social distance, and practice good hygiene until herd immunity is reached. This means that we must redouble efforts to convince the fence sitters that getting the vaccine can save not just their own lives but the lives of friends and families who may be immunocompromised.