February 28, 2023 - Update on Bivalent Boosters

Update on Bivalent Boosters

February 28, 2023

In my February 17 newsletter, I noted that I would like to see a second week of declining cases in the Birmingham metropolitan area before feeling confident that the mini-spike was under control. That data is now here and the favorable trend has continued. ADPH reported 4,605 new cases in Alabama for the week ending February 23, a 24% decline in one week and a decline of 53% compared to two weeks ago. These are the best weekly numbers since November. 

Whatever caused cases to rise in the Birmingham metropolitan area seems to have run its course. Both Jefferson County and Shelby County registered 17 cases per 100K population last week and St Clair had 19 cases per 100K, all of which are major improvements from two weeks ago.

If you received the updated bivalent booster which was introduced last September, you are one of just 7.7% of Alabama residents who are “fully vaccinated” (only Mississippi has a lower vaccination rate - 6.7%). You also might be wondering if you should consider getting a second bivalent booster shot before next fall. According to the CDC’s Advisory Committee on Immunization Practices (ACIP), which met last week to consider that question (among other things), the answer is “not yet”. 

Essentially, ACIP decided there was “insufficient evidence” to suggest older adults need another bivalent dose at this time, although ACIP left open the possibility that its recommendation could change if hospitalization rates among those who received the bivalent booster start to rise or the virus significantly mutates. Since the bivalent vaccine has been in use for only 6 months, and the incidence of severe cases remains low and manageable, ACIP seems satisfied to take a wait-and-see approach for now.

It’s clear that ACIP would like to move eventually to annual vaccinations, which mirrors the annual flu shot protocol, yet the propensity of Covid vaccines to begin to wane after 3-4 months could interfere with that goal. Since the principal goal of vaccines is to mitigate severe infection and prevent hospitalization, ACIP (and presumably the CDC) appears satisfied with annual vaccinations so long as severe infections remain under control. I will continue to monitor this issue and let you know of any future updates.