Dataset Information

Secondary transmission of SARS-CoV-2 during the first two waves in Japan: Demographic characteristics and overdispersion.

ABSTRACT:

Objectives

Super-spreading events caused by overdispersed secondary transmission are crucial in the transmission of COVID-19. However, the exact level of overdispersion, demographics, and other factors associated with secondary transmission remain elusive. In this study, we aimed to elucidate the frequency and patterns of secondary transmission of SARS-CoV-2 in Japan.

Methods

We analyzed 16,471 cases between January 2020 and August 2020. We generated the number of secondary cases distribution and estimated the dispersion parameter (k) by fitting the negative binomial distribution in each phase. The frequencies of the secondary transmission were compared by demographic and clinical characteristics, calculating the odds ratio using logistic regression models.

Results

We observed that 76.7% of the primary cases did not generate secondary cases with an estimated dispersion parameter k of 0.23. The demographic patterns of primary-secondary cases differed between phases, with 20-69 years being the predominant age group. There were higher proportions of secondary transmissions among older individuals, symptomatic patients, and patients with 2 days or more between onset and confirmation.

Conclusions

The study showed the estimation of the frequency of secondary transmission of SARS-CoV-2 and the characteristics of people who generated the secondary transmission.

SUBMITTER: Ko YK

PROVIDER: S-EPMC8772065 | biostudies-literature | 2022 Mar

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Secondary transmission of SARS-CoV-2 during the first two waves in Japan: Demographic characteristics and overdispersion.

Ko Yura K YK Furuse Yuki Y Ninomiya Kota K Otani Kanako K Akaba Hiroki H Miyahara Reiko R Imamura Tadatsugu T Imamura Takeaki T Cook Alex R AR Saito Mayuko M Suzuki Motoi M Oshitani Hitoshi H

International journal of infectious diseases : IJID : official publication of the International Society for Infectious Diseases 20220120

<h4>Objectives</h4>Super-spreading events caused by overdispersed secondary transmission are crucial in the transmission of COVID-19. However, the exact level of overdispersion, demographics, and other factors associated with secondary transmission remain elusive. In this study, we aimed to elucidate the frequency and patterns of secondary transmission of SARS-CoV-2 in Japan.<h4>Methods</h4>We analyzed 16,471 cases between January 2020 and August 2020. We generated the number of secondary cases ...[more]

PMID: 35066162

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Dataset Information

Secondary transmission of SARS-CoV-2 during the first two waves in Japan: Demographic characteristics and overdispersion.

Objectives

Methods

Results

Conclusions

Publications

Secondary transmission of SARS-CoV-2 during the first two waves in Japan: Demographic characteristics and overdispersion.

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