Park, Sang Woo; Sun, Kaiyuan; Abbott, Sam; Sender, Ron; Bar-On, Yinon M; Weitz, Joshua S; Funk, Sebastian; Grenfell, Bryan T; Backer, Jantien A; Wallinga, Jacco; +2 more... Viboud, Cecile; Dushoff, Jonathan; (2023) Inferring the differences in incubation-period and generation-interval distributions of the Delta and Omicron variants of SARS-CoV-2. Proceedings of the National Academy of Sciences of the United States of America, 120 (22). e2221887120-. ISSN 0027-8424 DOI: https://doi.org/10.1073/pnas.2221887120
Permanent Identifier
Use this Digital Object Identifier when citing or linking to this resource.
Abstract
Estimating the differences in the incubation-period, serial-interval, and generation-interval distributions of SARS-CoV-2 variants is critical to understanding their transmission. However, the impact of epidemic dynamics is often neglected in estimating the timing of infection-for example, when an epidemic is growing exponentially, a cohort of infected individuals who developed symptoms at the same time are more likely to have been infected recently. Here, we reanalyze incubation-period and serial-interval data describing transmissions of the Delta and Omicron variants from the Netherlands at the end of December 2021. Previous analysis of the same dataset reported shorter mean observed incubation period (3.2 d vs. 4.4 d) and serial interval (3.5 d vs. 4.1 d) for the Omicron variant, but the number of infections caused by the Delta variant decreased during this period as the number of Omicron infections increased. When we account for growth-rate differences of two variants during the study period, we estimate similar mean incubation periods (3.8 to 4.5 d) for both variants but a shorter mean generation interval for the Omicron variant (3.0 d; 95% CI: 2.7 to 3.2 d) than for the Delta variant (3.8 d; 95% CI: 3.7 to 4.0 d). The differences in estimated generation intervals may be driven by the "network effect"-higher effective transmissibility of the Omicron variant can cause faster susceptible depletion among contact networks, which in turn prevents late transmission (therefore shortening realized generation intervals). Using up-to-date generation-interval distributions is critical to accurately estimating the reproduction advantage of the Omicron variant.
Item Type | Article |
---|---|
Faculty and Department | Faculty of Epidemiology and Population Health > Dept of Infectious Disease Epidemiology & Dynamics (2023-) |
Research Centre | Centre for the Mathematical Modelling of Infectious Diseases |
PubMed ID | 37216529 |
Elements ID | 203276 |
Official URL | http://dx.doi.org/10.1073/pnas.2221887120 |
Download
Filename: Park-etal-2023-Inferring-the-differences-in-incubation.pdf
Licence: Creative Commons: Attribution-Noncommercial-No Derivative Works 4.0
Download