Household transmission of seasonal coronavirus infections: Results from the Flu Watch cohort study

Wellcome Open Research

article

Sarah Beale¹  Dan Lewer¹  Robert W. Aldridge¹  Anne M. Johnson³  Maria Zambon⁴  Andrew Hayward²  Ellen Fragaszy¹ 

[1] UCL Public Health Data Science Research Group, UCL Institute of Health Informatics, University College London;UCL Research Department of Epidemiology & Public Health, University College London;UCL Institute for Global Health, University College London;NIHR Health Protection Research Unit in Respiratory Infections, Imperial College London;Public Health England;Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine

关键词: coronavirus;    HCoV-NL63;    HCoV-OC43;    HCoV-229E;    SARS-CoV-2;    epidemiology;   

DOI  :  10.12688/wellcomeopenres.16055.1

学科分类：内科医学

来源: Wellcome

【 摘 要 】

Background: In the context of the current coronavirus disease 2019 (COVID-19) pandemic, understanding household transmission of seasonal coronaviruses may inform pandemic control. We aimed to investigate what proportion of seasonal coronavirus transmission occurred within households, measure the risk of transmission in households, and describe the impact of household-related factors of risk of transmission.Methods: Using data from three winter seasons of the UK Flu Watch cohort study, we measured the proportion of symptomatic infections acquired outside and within the home, the household transmission risk and the household secondary attack risk for PCR-confirmed seasonal coronaviruses. We present transmission risk stratified by demographic features of households.Results: We estimated that the proportion of cases acquired outside the home, weighted by age and region, was 90.7% (95% CI 84.6- 94.5,n=173/195) and within the home was 9.3% (5.5-15.4, 22/195). Following a symptomatic coronavirus index case, 14.9% (9.8 - 22.1, 20/134) of households experienced symptomatic transmission to at least one other household member. Onward transmission risk ranged from 11.90% (4.84-26.36, 5/42) to 19.44% (9.21-36.49, 7/36) by strain. The overall household secondary attack risk for symptomatic cases was 8.00% (5.31-11.88, 22/275), ranging across strains from 5.10 (2.11-11.84, 5/98) to 10.14 (4.82- 20.11, 7/69). Median clinical onset serial interval was 7 days (IQR= 6-9.5). Households including older adults, 3+ children, current smokers, contacts with chronic health conditions, and those in relatively deprived areas had the highest transmission risks. Child index cases and male index cases demonstrated the highest transmission risks.Conclusion: Most seasonal coronaviruses appear to be acquired outside the household, with relatively modest risk of onward transmission within households. Transmission risk following an index case appears to vary by demographic household features, with potential overlap between those demonstrating the highest point estimates for seasonal coronavirus transmission risk and COVID-19 susceptibility and poor illness outcomes.

【 授权许可】

CC BY