by W. Robert Graham, MD
February 22, 2021
Take for example the Moderna vaccine trial, published in the New England Journal of Medicine beginning in November with follow-up publications extending through February. In that trial they randomized 15,210 people to the vaccine and 15,210 people to placebo. Of those who got the placebo, 185 developed COVID-19. Therefore, 1.2% got COVID-19. Thirty of those became very ill. Of those who got the vaccine, 11 developed COVID-19. None of them got very ill. Therefore, 0.07% got COVID-19. So, the vaccine was effective: it prevented illness and it prevented serious illness.
The efficacy of the vaccine is quoted as 94%. That figure is arrived at by dividing 0.07 by 1.2, which equals 6%. Subtracting that from 100% equals 94%.
This messaging is in part driven by the fact that we live in a media age that needs talking points. To say that the vaccine is effective is not a dramatic talking point. But as soon as you suggest that it may not work for spread of the illness, people prick up their ears.
Experts fall prey to the same psychology. Such talking points allow them to go on television and pontificate. Some experts even like to make things more complicated than they need to be, and some have great fears about being seen as wrong. One way to avoid that is to equivocate, to harp on what we don’t know because to be too definitive is to run the risk of someone finding one example of spread and then say, “Look, he was wrong.”
It is very unlikely that two weeks after a person receives the second COVID-19 vaccine that he or she will spread the virus. Nevertheless, it is a rare possibility. There were those 11 people out of 15,210 who developed COVID-19. Therefore, wearing masks after getting the vaccine is justified. But what is not justified is spreading the word that spread of the virus after vaccination is a serious threat. What is not justified is giving people a talking point which is used to say that the vaccine does not work.