Sept 9, 2022 Covid Update
With the introduction of the new bivalent version of the Moderna and Pfizer Covid vaccines, there is a lot of confusion on who should get it. Officially, the CDC recommends the new booster now for anyone over age 50 who has not received a booster in the last two months. Nonetheless, there is a lot of discussion about whether this is the best advice.
The bivalent version of the vaccine contains mRNA components of the original Covid strain plus the Omicron BA.4 and BA.5 strains. The hope is infections will be reduced by expanding the coverage of the vaccine to the very contagious Omicron variants currently circulating. We have seen that even with four vaccines total (the two initial doses plus two boosters) of Pfizer or Moderna there are still many breakthrough infections.
The Omicron variant tends to be much more of an upper respiratory infection (such as a head cold or sinus infection) and is not infecting the lungs that much. Consequently, it is not sending people to the hospital or killing them nearly as frequently as the original strains and the first few variants.
Of course, more people have antibodies to Covid now from either being vaccinated or having caught Covid or both. This increased immunity in the population has also helped reduce the death rate. Here in Arizona, the weekly death rate was down to 48 (from 66) this past week and the number of hospitalizations has remained low. This trend is very encouraging.
A large part of the discussion about whether to get another Covid booster now is that this new booster was approved before any human studies looking at its effectiveness were completed. While there is little worry about the safety of getting a fifth Covid vaccine, there are questions about the timing of when to get it, and if it will be as effective as desired.
The model of changing a vaccine without any human studies is not new and is the one used for flu shots. Several experts are even speculating that like flu shots Covid vaccines will become a once-a-year event. However, everything is still relatively new with Covid, and it remains unclear if this will truly be the case. In addition, it is still not fully understood what the optimal regimen for boosters is.
Despite all of that, there are certain individuals who should get the new bivalent booster by the middle of October. First off, anyone who is immunocompromised either from medication/chemotherapy or underlying medical conditions should receive a third booster (fifth shot total). Diabetics and those with lung disease should also get a shot now, as well as anyone over age 75.
If you have received only one booster (three Covid shots total), you should get the new bivalent dose now as your second booster/fourth shot.
Finally, if you have had a Covid infection in the last ninety days you do not need a booster at this time as the infection gave you protection (although you can get Omicron again relatively quickly). If you wish to wait and see if getting a third booster/fifth shot total is truly beneficial and you are not in a high-risk category, then I believe waiting another month or two is totally reasonable at this moment in time. Naturally, as I always remind people, the advice regarding Covid is constantly evolving so what we recommend today may change tomorrow.