Updated booster doses by state: This week, the CDC started reporting how many people have received the bivalent, Omicron-specific boosters by state, including state-level data for several demographic groups (over age 5, over 12, over 18, and over 65). The numbers are low: Vermont and Washington, D.C. have the highest booster rates as of November 9, with 21% and 20% of their populations receiving the bivalent shots, respectively. In about half of states, less than 10% of the population has received an updated booster. (H/t Jason Salemi.)
Additional data suggests new boosters work against BQs: Speaking of the updated booster shots, a recent preprint from researchers at Emory University, Stanford University, and the NIH found that the new boosters produced several times more neutralizing antibodies against subvariants BQ.1.1 and BA.2.75.2 compared to the older vaccines. This was a small lab study and hasn’t yet been peer-reviewed, but it follows similar evidence from other research suggesting that the new boosters do provide additional protection against the most concerning variants currently circulating in the U.S. (See last week’s post.) If you haven’t gotten a bivalent booster yet, now is a good time!
More evidence that masks in schools prevent COVID-19 spread: Another notable new study this week, published in the New England Journal of Medicine: a group of researchers from Boston institutions examined the differences in COVID-19 case numbers between public school districts that kept mask requirements in place during spring 2022, and those that lifted their requirements upon a statewide policy change in February. Overall, ending required masking led to “an additional 44.9 COVID-19 cases per 1,000 students and staff” during the remainder of the semester, the researchers found. The study demonstrates that masks are still a useful public health strategy to reduce illness—and risk of Long COVID—in schools.
Paxlovid may reduce Long COVID risk: When Paxlovid first became available earlier in the year, some Long COVID patients reported that the drug helped alleviate their symptoms. A new study from Ziyad Al-Aly and his team at the Veterans Affairs St. Louis healthcare system provides evidence behind the anecdotal reports, finding that veterans treated with Paxlovid had a 25% lower risk of long-term symptoms, based on their electronic health records. The study has received some criticism (and has not yet been peer-reviewed); to me, it provides motivation for actual clinical trials examining Paxlovid’s use for treating Long COVID. RECOVER is running one such trial, but it won’t start until early 2023.
Estimating COVID-19 infections from wastewater: And one more study that caught my attention this week: researchers at the University of Florida used a modeling technique called a “mass balance equation” to estimate how many people in Gainseville, Florida were sick with COVID-19 based on the virus’ concentration in wastewater. Using about one year of wastewater data (May 2020 to May 2021), the researchers were able to accurately predict actual infections with an error of just 1%. Translating wastewater data into useful information for public health action has been a major challenge for the growing field, so I was glad to see this study providing a potentially-useful method.