Vaccine breakthrough infections in a highly-vaccinated Australian population during a SARS-CoV-2 Delta outbreak
DOI:
https://doi.org/10.33321/cdi.2022.46.32Keywords:
COVID-19 breakthrough infections, Australian Capital Territory, COVID-19, outbreak, SARS-CoV-2 Delta, vaccinationAbstract
Over 80% of residents in the Australian Capital Territory were fully vaccinated within 10 weeks of a SARS-CoV-2 Delta variant outbreak. Of the outbreak’s 1,545 cases, 10% were breakthrough infections. The incidence of infections among fully- and partially-vaccinated people was 98.5% and 90% lower, respectively, than for unvaccinated people.
Downloads
References
Australian Capital Territory Government. COVID-19: Seven-day lockdown for the ACT. [Internet.] Canberra: Australian Capital Territory Government; 12 August 2021. [Accessed on 6 November 2021.] Available from: https://www.covid19.act.gov.au/news-articles/seven-day-lockdown-for-the-act.
Australian Government Department of Health. COVID-19 vaccination – COVID-19 vaccination Phase 1A rollout presentation. [Internet.] Canberra: Australian Government Department of Health; 18 February 2021. [Accessed on 27 November 2021.] Available from: https://www.health.gov.au/resources/publications/covid-19-vaccination-covid-19-vaccination-phase-1a-rollout-presentation.
Australian Government Department of Health. Coronavirus Disease 2019 (COVID-19). CDNA National guidelines for public health units. [Internet.] Canberra: Australian Government Department of Health; 2021. [Accessed on 6 November 2021.] Available from: https://www1.health.gov.au/internet/main/publishing.nsf/Content/cdna-song-novel-coronavirus.htm
Klompas M. Understanding breakthrough infections following mRNA SARS-CoV-2 vaccination. JAMA. 2021;326(20):2018–20. doi: https://doi.org/10.1001/jama.2021.19063.
Elliott P, Haw D, Wang H, Eales O, Walters CE, Ainslie KEC et al. Exponential growth, high prevalence of SARS-CoV-2, and vaccine effectiveness associated with the Delta variant. Science. 2021;374(6574):eabl9551. doi: https://doi.org/10.1126/science.abl9551.
Kaslow DC. Force of infection: a determinant of vaccine efficacy? NPJ Vaccines . 2021;6(1):51. doi: https://doi.org/10.1038/s41541-021-00316-5.
Lei H, Xu X, Xiao S, Wu X, Shu Y. Household transmission of COVID-19—a systematic review and meta-analysis. J Infect. 2020;81(6):979–97. doi: https://doi.org/10.1016/j.jinf.2020.08.033.
Singanayagam A, Hakki S, Dunning J, Madon KJ, Crone MA, Koycheva A et al. Community transmission and viral load kinetics of the SARS-CoV-2 delta (B.1.617.2) variant in vaccinated and unvaccinated individuals in the UK: a prospective, longitudinal, cohort study. Lancet Infect Dis. 2022;22(2):183–95. doi: https://doi.org/10.1016/S1473-3099(21)00648-4.
Mizrahi B, Lotan R, Kalkstein N, Peretz A, Perez G, Ben-Tov A et al. Correlation of SARS-CoV-2-breakthrough infections to time-from-vaccine. Nat Commun. 2021;12(1):6379. doi: https://doi.org/10.1038/s41467-021-26672-3.
Published
How to Cite
Issue
Section
Categories
License
Copyright (c) 2022 Communicable Diseases Intelligence

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
