Dataset Information

Behavioral factors and SARS-CoV-2 transmission heterogeneity within a household cohort in Costa Rica.

ABSTRACT:

Introduction

Variability in household secondary attack rates and transmission risks factors of SARS-CoV-2 remain poorly understood.

Methods

We conducted a household transmission study of SARS-CoV-2 in Costa Rica, with SARS-CoV-2 index cases selected from a larger prospective cohort study and their household contacts were enrolled. A total of 719 household contacts of 304 household index cases were enrolled from November 21, 2020, through July 31, 2021. Blood specimens were collected from contacts within 30-60 days of index case diagnosis; and serum was tested for presence of spike and nucleocapsid SARS-CoV-2 IgG antibodies. Evidence of SARS-CoV-2 prior infections among household contacts was defined based on the presence of both spike and nucleocapsid antibodies. We fitted a chain binomial model to the serologic data, to account for exogenous community infection risk and potential multi-generational transmissions within the household.

Results

Overall seroprevalence was 53% (95% confidence interval (CI) 48-58%) among household contacts. The estimated household secondary attack rate is 34% (95% CI 5-75%). Mask wearing by the index case is associated with the household transmission risk reduction by 67% (adjusted odds ratio = 0.33 with 95% CI: 0.09-0.75) and not sharing bedroom with the index case is associated with the risk reduction of household transmission by 78% (adjusted odds ratio = 0.22 with 95% CI 0.10-0.41). The estimated distribution of household secondary attack rates is highly heterogeneous across index cases, with 30% of index cases being the source for 80% of secondary cases.

Conclusions

Modeling analysis suggests that behavioral factors are important drivers of the observed SARS-CoV-2 transmission heterogeneity within the household.

SUBMITTER: Sun K

PROVIDER: S-EPMC10363136 | biostudies-literature | 2023 Jul

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Behavioral factors and SARS-CoV-2 transmission heterogeneity within a household cohort in Costa Rica.

Sun Kaiyuan K Loria Viviana V Aparicio Amada A Porras Carolina C Vanegas Juan Carlos JC Zúñiga Michael M Morera Melvin M Avila Carlos C Abdelnour Arturo A Gail Mitchell H MH Pfeiffer Ruth R Cohen Jeffrey I JI Burbelo Peter D PD Abed Mehdi A MA Viboud Cécile C Hildesheim Allan A Herrero Rolando R Prevots D Rebecca DR

Communications medicine 20230722 1

<h4>Introduction</h4>Variability in household secondary attack rates and transmission risks factors of SARS-CoV-2 remain poorly understood.<h4>Methods</h4>We conducted a household transmission study of SARS-CoV-2 in Costa Rica, with SARS-CoV-2 index cases selected from a larger prospective cohort study and their household contacts were enrolled. A total of 719 household contacts of 304 household index cases were enrolled from November 21, 2020, through July 31, 2021. Blood specimens were collect ...[more]

PMID: 37481623

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Dataset Information

Behavioral factors and SARS-CoV-2 transmission heterogeneity within a household cohort in Costa Rica.

Introduction

Methods

Results

Conclusions

Publications

Behavioral factors and SARS-CoV-2 transmission heterogeneity within a household cohort in Costa Rica.

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