Vaccine Recommendations

Retirement or not, I’m still fielding a lot of questions about whether to get the COVID booster, so I thought I’d give you my ideas.

The first thing to be aware of is that there’s not an absolute answer. It’s a different answer for, say, a healthy 25 year old versus a 68 year old with diabetes and chronic bronchitis. The second issue is what you can and can’t expect from a vaccine. Vaccines only work on a PORTION of the immune system. They ramp up the antibodies against the virus, called the “B” cells. A similarly important component of the immune system, called the “T” cells or lymphocytes, is not helped by the vaccine. And so, if someone has limited T cell activity, they will have a limited immunity toward the virus, vaccine or not.

The third issue is the expectations of the booster itself. It does not, in general, prevent people from catching the COVID virus. It does, to a large extent, modify how sick someone gets and it definitely lowers the rate of hospitalization and death from the virus, particularly when one is high-risk (more on that later).

The fourth issue has to do with what’s called variants. The clever virus keeps changing itself just enough to fool the immune response. These changes are called variants. Delta and Omicron were significant variants, and different variants of Omicron have also popped up. The current version, which is very contagious, is called B 4/5 or B 5, and it’s currently responsible for around 95% of new infection as of last month. So a vaccine can be formulated and jump through the hoops necessary to bring it to market, and by the time it’s available a new variant has appeared and taken over. The drug companies are in the unenviable role of having to guess what the new variants will be. This is how the flu vaccines are chosen every year, and it’s not always effective.

We do know that there’s some overlap between original and variants, so that people who were primarily vaccinated last year still have some immunity, not as much as when they were first vaccinated. In fact, genes are make up by pairs of amino acids in a framework called a double helix. There are actually only 4 mutations out of 4000 that vary between the original and BA 5 variants. So it’s tempting (though not proven) to think that the immunity overlaps.

When we look at effectiveness in keeping people alive and out of hospitals, the main benefit is in the 50-75 year old group, where statistics from a variety of sources support the preventive aspect of the booster. By booster I’m referring to the so-called BiValent booster developed by both Moderna and Pfizer. Below 50 years old, there is not much difference in hospitalization between those who’ve gotten the booster and those who are unvaccinated.

We don’t yet have information on whether the booster prevents the development of Long COVID. And there aren’t good human studies on the exact variant being used. And then there’s the question of how much to trust a drug company boasting about their latest drug? (hint: not much). But we can suggest some general guidelines regarding the latest booster.

If you’re older than 50, and certainly older than 65, and your main goal is staying out of the hospital, then it is advisable to consider getting boosted. If you’re any age and have a chronic disease or otherwise weakened immune system, consider getting boosted. If you work in high-risk situations (say, an ER) or are around a lot of people (say, frequent fliers), consider getting boosted. And if you’re someone who will sleep better at night knowing you have the best protection that medicine can offer, consider getting boosted. And if you are young, healthy, socially isolated, or fearful of any medical intervention, you may consider not getting boosted.