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A mathematical model reveals the influence of population heterogeneity on herd immunity to SARS-CoV-2.

ABSTRACT: Despite various levels of preventive measures, in 2020 many countries have suffered severely from the coronavirus 2019 (COVID-19) pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus. We show that population heterogeneity can significantly impact disease-induced immunity as the proportion infected in groups with the highest contact rates is greater than in groups with low contact rates. We estimate that if R 0 = 2.5 in an age-structured community with mixing rates fitted to social activity then the disease-induced herd immunity level can be around 43%, which is substantially less than the classical herd immunity level of 60% obtained through homogeneous immunization of the population. Our estimates should be interpreted as an illustration of how population heterogeneity affects herd immunity, rather than an exact value or even a best estimate.

SUBMITTER: Britton T

PROVIDER: S-EPMC7331793 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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A mathematical model reveals the influence of population heterogeneity on herd immunity to SARS-CoV-2.

Britton Tom T Ball Frank F Trapman Pieter P

Science (New York, N.Y.) 20200623 6505

Despite various levels of preventive measures, in 2020, many countries have suffered severely from the coronavirus disease 2019 (COVID-19) pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus. Using a model, we show that population heterogeneity can affect disease-induced immunity considerably because the proportion of infected individuals in groups with the highest contact rates is greater than that in groups with low contact rates. We estimate that if <i>R< ...[more]

PMID: 32576668

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