Effectiveness of Monovalent mRNA Vaccines Against COVID-19-Associated Hospitalization Among Immunocompetent Adults During BA.1/BA.2 and BA.4/BA.5 Predominant Periods of SARS-CoV-2 Omicron Variant in the United States - IVY Network, 18 States, December 26, 2021-August 31, 2022
Author Department
Pulmonary/Critical Care Medicine
Document Type
Article, Peer-reviewed
Publication Date
10-2022
Abstract
The SARS-CoV-2 Omicron variant (B.1.1.529 or BA.1) became predominant in the United States by late December 2021 (1). BA.1 has since been replaced by emerging lineages BA.2 (including BA.2.12.1) in March 2022, followed by BA.4 and BA.5, which have accounted for a majority of SARS-CoV-2 infections since late June 2022 (1). Data on the effectiveness of monovalent mRNA COVID-19 vaccines against BA.4/BA.5-associated hospitalizations are limited, and their interpretation is complicated by waning of vaccine-induced immunity (2-5). Further, infections with earlier Omicron lineages, including BA.1 and BA.2, reduce vaccine effectiveness (VE) estimates because certain persons in the referent unvaccinated group have protection from infection-induced immunity. The IVY Network† assessed effectiveness of 2, 3, and 4 doses of monovalent mRNA vaccines compared with no vaccination against COVID-19-associated hospitalization among immunocompetent adults aged ≥18 years during December 26, 2021-August 31, 2022. During the BA.1/BA.2 period, VE 14-150 days after a second dose was 63% and decreased to 34% after 150 days. Similarly, VE 7-120 days after a third dose was 79% and decreased to 41% after 120 days. VE 7-120 days after a fourth dose was 61%. During the BA.4/BA.5 period, similar trends were observed, although CIs for VE estimates between categories of time since the last dose overlapped. VE 14-150 days and >150 days after a second dose was 83% and 37%, respectively. VE 7-120 days and >120 days after a third dose was 60%and 29%, respectively. VE 7-120 days after the fourth dose was 61%. Protection against COVID-19-associated hospitalization waned even after a third dose. The newly authorized bivalent COVID-19 vaccines include mRNA from the ancestral SARS-CoV-2 strain and from shared mRNA components between BA.4 and BA.5 lineages and are expected to be more immunogenic against BA.4/BA.5 than monovalent mRNA COVID-19 vaccines (6-8). All eligible adults aged ≥18 years§ should receive a booster dose, which currently consists of a bivalent mRNA vaccine, to maximize protection against BA.4/BA.5 and prevent COVID-19-associated hospitalization.
Recommended Citation
Surie D, Bonnell L, Adams K, Gaglani M, Ginde AA, Douin DJ, Talbot HK, Casey JD, Mohr NM, Zepeski A, McNeal T, Ghamande S, Gibbs KW, Files DC, Hager DN, Shehu A, Frosch AP, Erickson HL, Gong MN, Mohamed A, Johnson NJ, Srinivasan V, Steingrub JS, Peltan ID, Brown SM, Martin ET, Khan A, Bender WS, Duggal A, Wilson JG, Qadir N, Chang SY, Mallow C, Rivas C, Kwon JH, Exline MC, Lauring AS, Shapiro NI, Halasa N, Chappell JD, Grijalva CG, Rice TW, Stubblefield WB, Baughman A, Womack KN, Hart KW, Swan SA, Zhu Y, DeCuir J, Tenforde MW, Patel MM, McMorrow ML, Self WH; IVY Network. Effectiveness of Monovalent mRNA Vaccines Against COVID-19-Associated Hospitalization Among Immunocompetent Adults During BA.1/BA.2 and BA.4/BA.5 Predominant Periods of SARS-CoV-2 Omicron Variant in the United States - IVY Network, 18 States, December 26, 2021-August 31, 2022. MMWR Morb Mortal Wkly Rep. 2022 Oct 21;71(42):1327-1334. doi: 10.15585/mmwr.mm7142a3.
PMID
36264830