Affiliation:
1. Department of Epidemiology and Biostatistics, School of Public Health Peking University Beijing China
2. Institute for Infectious Disease and Endemic Disease Control Beijing Center for Disease Prevention and Control Beijing China
3. Department of Laboratory Science and Technology & Vaccine Research Center, School of Public Health Peking University Beijing China
4. State Key Laboratory of Pathogen and Biosecurity Beijing Institute of Microbiology and Epidemiology Beijing China
5. Key Laboratory of Epidemiology of Major Diseases (Peking University) Ministry of Education Beijing China
Abstract
AbstractThe transmissibility is a crucial feature for norovirus, yet its quantitative estimation has been limited. Our objective was to estimate the basic reproduction number (R0) of norovirus and investigate its variation characteristics. Norovirus outbreaks reported from September 2016 to August 2021 in Beijing were analyzed. The susceptible‐infected‐removed compartment model was established to estimate R0. Linear regression models and logistic regression models were used to explore the factors affecting the transmissibility of norovirus. The overall median R0 of norovirus was estimated as 2.1 (interquartile range [IQR] 1.8–2.5), with 650 norovirus outbreaks. The transmissibility of norovirus varied by year, outbreak setting and genotype. The R0 of norovirus during September 2019 to August 2020 (median 2.1, IQR 1.8–2.4) and September 2020 to August 2021 (median 2.0, IQR 1.7–2.3) was lower than that of September 2016 to August 2017 (median 2.3, IQR 1.8–2.7) (β = 0.94, p = 0.05; β = 0.93, p = 0.008). The R0 of norovirus for all other settings was lower than that for kindergarten (median 2.4, IQR 2.0–2.9) (primary school: median 2.0, IQR 1.7–2.4, β = 0.94, p = 0.001; secondary school: median 1.7, IQR 1.5–2.0, β = 0.87, p < 0.001; college: median 1.7, IQR 1.5–1.8, β = 0.89, p = 0.03; other closed settings: median 1.8, IQR 1.5–2.0, β = 0.90, p = 0.004). GⅡ.2[P16] outbreaks had a median R0 of 2.2 (IQR 1.8–2.7), which was higher than that for GⅡ.6[P7] outbreaks (median 1.8, IQR: 1.8–2.0, odds ratio = 0.19, p = 0.03; GⅡ.2[P16] as reference) and mixed‐genotype outbreaks (median 1.7, IQR: 1.5–1.8, β = 0.92, p = 0.02; mixed‐genotype as reference). In kindergartens and primary schools, norovirus shows increased transmissibility, emphasizing the vulnerable population and high‐risk settings. Furthermore, the transmissibility of norovirus may change over time and with virus evolution, necessitating additional research to uncover the underlying mechanisms.
Subject
Infectious Diseases,Virology