Vaccine effectiveness against COVID‐19 among symptomatic persons aged ≥12 years with reported contact with COVID‐19 cases, February–September 2021. Issue 4 (15th February 2022)

• Record Type: Journal Article
• Authors: Chung, Jessie R.; Kim, Sara S.; Belongia, Edward A.; McLean, Huong Q.; King, Jennifer P.; Nowalk, Mary Patricia; Zimmerman, Richard K.; Moehling Geffel, Krissy; Martin, Emily T.; Monto, Arnold S.; Lamerato, Lois E.; Gaglani, Manjusha; Hoffman, Eric; Volz, Marcus; Jackson, Michael L.; Jackson, Lisa A.; Patel, Manish M.; Flannery, Brendan
• Is Part Of: Influenza and other respiratory viruses. Volume 16:Issue 4(2022)
• Page Start: 673
• Page End: 679
• Publication Date: 2022-02-15
• Subjects: COVID‐19 -- SARS‐CoV‐2 -- vaccine effectiveness; Influenza -- Periodicals; Respiratory infections -- Periodicals; Virus diseases -- Periodicals; Influenza, Human -- Periodicals; Respiratory Tract Diseases -- Periodicals; Virus Diseases -- Periodicals; Grippe -- Périodiques; Appareil respiratoire -- Infections -- Périodiques; Maladies à virus -- Périodiques; 616.203
• DOI: 10.1111/irv.12973
• Languages: English
• ISSNs: 1750-2640

Abstract

Abstract: Background: Individuals in contact with persons with COVID‐19 are at high risk of developing COVID‐19; protection offered by COVID‐19 vaccines in the context of known exposure is poorly understood. Methods: Symptomatic outpatients aged ≥12 years reporting acute onset of COVID‐19‐like illness and tested for SARS‐CoV‐2 between February 1 and September 30, 2021 were enrolled. Participants were stratified by self‐report of having known contact with a COVID‐19 case in the 14 days prior to illness onset. Vaccine effectiveness was evaluated using the test‐negative study design and multivariable logistic regression. Results: Among 2229 participants, 283/451 (63%) of those reporting contact and 331/1778 (19%) without known contact tested SARS‐CoV‐2‐positive. Adjusted vaccine effectiveness was 71% (95% confidence interval [CI], 49%–83%) among fully vaccinated participants reporting a known contact versus 80% (95% CI, 72%–86%) among those with no known contact ( p ‐value for interaction = 0.2). Conclusions: This study contributes to growing evidence of the benefits of vaccinations in preventing COVID‐19 and support vaccination recommendations and the importance of efforts to increase vaccination coverage.