Bivalent mRNA Vaccines Proven More Effective at Preventing COVID-19 Hospitalization & Death
A new study published in the New England Journal of Medicine has found that updated bivalent mRNA vaccines are more effective than original monovalent vaccines at preventing COVID-19 hospitalization and death.[0] The study was conducted by researchers at the University of North Carolina’s Gillings School of Global Public Health and compared the efficacy of the bivalent BA.1 or BA.4-5 mRNA-booster vaccines administered as the fourth vaccine dose against SARS-CoV-2-related hospitalization and mortality during the prevalence of the Omicron BA.4-5 subvariant.[1]
The study found that the bivalent booster was slightly better at generating virus-fighting antibodies than in previous studies, which found only small differences between people boosted with the original and bivalent vaccines in terms of antibodies generated against BQ.1.1 and XBB.1. It also showed that the bivalent booster provided 48 percent greater protection against symptomatic infection from the XBB and XBB.1.5 subvariants among people who had the booster in the previous two to three months, compared with people who had only previously received two to four monovalent doses.
The US Centers for Disease Control and Prevention (CDC) also provided the first estimates of the effectiveness of bivalent mRNA COVID-19 vaccines against the newest dominant Omicron subvariant of SARS-CoV-2.[2] The study found that among people aged 65 and older, the effectiveness against infection by XBB and XBB.1.5 viruses was 43%, compared to 37% against the BA.5 viruses.
The study also looked at the reasons why some people did not receive the bivalent booster. Among those who did not receive it at the time of initial evaluation, the most prevalent reasons were being too busy, forgetting, and fearing adverse effects.[3]
In conclusion, the study found that the bivalent booster offered greater protection against symptomatic infection from the XBB and XBB.1.5 subvariants than the original monovalent doses. Additionally, older adults were more likely to benefit from the bivalent booster, as the effectiveness against infection by XBB and XBB.1.5 viruses was 43%, compared to 37% against the BA.5 viruses.
0. “Effectiveness of Bivalent Boosters against Severe Omicron Infection | NEJM” nejm.org, 25 Jan. 2023, https://www.nejm.org/doi/full/10.1056/NEJMc2215471
1. “Bivalent BA.4-5 or BA.1 mRNA-booster given as a fourth dose associated with increased protection against COVID-19 hospitalization and death” News-Medical.Net, 23 Jan. 2023, https://www.news-medical.net/news/20230123/Bivalent-BA4-5-or-BA1-mRNA-booster-given-as-a-fourth-dose-associated-with-increased-protection-against-COVID-19-hospitalization-and-death.aspx
2. “CDC Releases First Estimates of Bivalent mRNA COVID-19 Booster Effectiveness against XBB/XBB.1.5” Patient Care Online, 25 Jan. 2023, https://www.patientcareonline.com/view/cdc-releases-first-estimates-of-bivalent-mrna-covid-19-booster-effectiveness-against-xbb-xbb-1-5
3. “Survey of previously vaccinated US residents finds the most common reasons for not getting an updated COVID-19 vaccine” News-Medical.Net, 24 Jan. 2023, https://www.news-medical.net/news/20230124/Survey-of-previously-vaccinated-US-residents-finds-the-most-common-reasons-for-not-getting-an-updated-COVID-19-vaccine.aspx