Do you need a booster dose of COVID-19 vaccine?

Yesterday an article in The Lancet provided an independent scientific assessment of the need for COVID-19 vaccine booster doses. The publication reviewed the current data on booster vaccines, which generally shows very good efficacy even with the Delta variant for the mRNA based vaccines from Pfizer and Moderna.

The general tone of the article  suggested that current efficacy is more than adequate to avoid infection, but more importantly, effectively prevents severe illness causing hospitalization or death. 

This publication generated a fair amount of political commentary since two of the authors, Philip Krause and Marion Gruber, were senior vaccine review officials at the FDA that have had recently resigned from the agency. This was reportedly due to a disagreement with the Biden administration’s push for vaccine boosters. But that discussion was really a distraction from the central message surrounding of this publication.

The real point of the article was that, “Current evidence does not appear to show a need for boosting in the general population, in which efficacy against severe disease remains high.” The authors relate this to the fact that antibody immunity, which is what is usually measured in the blood, is not central to protection from severe disease. “This protection could be because protection against severe disease is mediated not only by antibody responses, which might be relatively short lived for some vaccines, but also by memory responses and cell-mediated immunity, which are generally longer lived.”

More importantly, the authors of this article believed, “The limited supply of these vaccines means they will save the most lives if made available to people who are at appreciable risk of serious disease and have not yet received any vaccine. Even if some gain can ultimately be obtained from boosting, it will not outweigh the benefits of providing initial protection to the unvaccinated.”

Of interest, reports of the article by the New York Times and the WSJ presented the conclusions without comment, however a prior editorial in the WSJ took the opposite tack arguing for boosters. This prompted me to review the potential benefits for booster vaccines, especially given these shots would appear to have little risk given the safety of vaccine’s first and second doses (although this has not been proven yet).

Most of the data on booster vaccine benefits comes from Israel, where the population was immunized early on with the Pfizer vaccine. The data has been reported to suggest the booster has been effective in blunting the recent Delta variant driven surge in COVID-19 cases. However, this data only reflects a few weeks of activity after the boosters have been given, so we don’t know the long term benefit. Importantly, cases are falling dramatically in both those with only two vaccine doses and those with boosters, so the benefit of the booster isn’t clear.

What is driving the current, Delta driven surge in infections is also interesting. The number of people hospitalized is greatest in the U.S., which is due to its overall low vaccination rate. But it is interesting to see the UK and Israel with high numbers, given they are thought to be highly vaccinated.

It turns out though, that Israel has a much lower rate of vaccination than most people think, especially compared to other developed countries.

Israel actually lags in population vaccination percentage worldwide compared with other developed nations. Note, the US is not listed here because it currently ranks 37th!

So again, it is the unvaccinated who are driving this surge, not individuals with two vaccine doses who need a booster.

Bottom line, if you want a third, booster vaccine shot, and it is available, you can have it with little risk. But the only way to stop the current surge is to vaccinate the people without any vaccine coverage! That is the real message from the Lancet publication.

Published by jbakerjrblog

Immunologist, former Army MD, former head of allergy and clinical immunology at University of Michigan, vaccine developer and opinionated guy.

3 thoughts on “Do you need a booster dose of COVID-19 vaccine?

  1. I think we badly need an explanation of how a MRNA vaccine works. The account I read in NATURE a couple of days ago told me everything about these vaccines except what I wanted to know. The article explained the problems involved in creating a vehicle for MRNA, but never really explained how MRNA works inside the body. My very vague understanding is that MRNA can be engineered to carry a code that instructs cells as to how to create antibodies to combat specific viruses. What I, and the public, need to know is just how this code is created and how it is transmitted. Furthermore, does the MRNA enter just the cell or its nucleus as well? I’m sure the explanation a very complicated one, but until we can find a way to explain how these vaccines work, a way the average person can understand, false accounts of how they work will spread and metastasize. I am a teacher. I have had great success in explaining complex ideas, and I have been trying to do this online to eradicate falsehoods about COVID19, but I can only explained what I already understand.


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