Issues in COVID-19 research and statistical analyses (Part XVVXVVIV)
November 23, 2022
In an article from November 11, 2022 in Health News from NPR, Rob Stein lays out the likelihood of two new Omicron subvariants, BQ.1 and BQ.11 of SARS-Cov-2 having become dominant in the United States and leading to a winter surge in cases. These two subvariants have overtaken Ba.5 in the recent weeks. They state the recent laboratory studies indicated that newer mutations in the spike protein of this virus appear to make these variants more immune-evasive than Ba.5. The experts are hoping prior immunity people would have from previous infections and maybe vaccination would help protect but a more recent study had indicated that get reinfected can post risks in either the short or long-term and can lead to increased risk of severe COVID, long COVID and death.
This leads to the idea that one would gain enhanced protection from the new bivalent boosters put out by both Pfizer and Moderna. However, there has been conflicting evidence of their usefulness. A study by researchers at Columbia University showed that the new boosters are no better than the original vaccine given as fourth dose. Wang et al report in a pre-print article their findings of comparing people with several doses of the mRNA vaccines to those receiving the new bivalent mRNA vaccine as a 4th dose. They found after 3 to 4 weeks that those receiving a 4th dose of a monovalent mRNA vaccine had the same level of neutralizing antibody titers as compared to those receiving a bivalent mRNA vaccine as a 4th dose. The only statistics they used were written in the footnote of their Figure 1 which shows the neutralization profiles of serum samples from these different groups against the SARS-CoV-2 variants. They used Mann-Whitney U-tests to make the comparisons between groups amongst different lineages of the SARS-CoV-2. One thing they didn’t try to correct for which they mentioned is a distinction is those who received the monovalent boosters were on average older, 55.3 years as compared to those who received the bivalent booster, 36.4 years old. They found that there were no statistically significant differences in neutralization of any SARS-CoV-2 variant compared between persons who received the monovalent four doses vs bivalent as the 4th dose. However given their lack of any adjustment for confounding, these results are still open for interpretation.
Keywords: COVID-19, vaccination, omicron subvariants, booster vaccination
Stein, Rob (November 11, 2022) “New omicron subvariants now dominant in the U.S. raising fears of a winter surge”. https://www.npr.org/sections/health-shots/2022/11/11/1136039817/new-omicron-subvariants-now-dominant-in-the-u-s-raising-fears-of-a-winter-surge .
Qian Wang, Anthony Bowen, Riccardo Valdez, Carmen Gherasim, Aubree Gordon, Lihong Liu, David D. Ho
bioRxiv 2022.10.22.513349; doi: https://doi.org/10.1101/2022.10.22.513349