Transmission of SARS-CoV-2 within Dutch households

In December 2019 the first infections of SARS-CoV-2 (COVID-19 disease) were detected in Wuhan, China. The first COVID-19 case in the Netherlands was confirmed on February 27, 2020. In March 2020, the Dutch government mandated a partial lockdown, characterized by social distancing, self-quarantine, closing of schools, bars, and restaurants, and urging people to work from home. As household members live in close contact, the household constitutes a high risk setting for SARS-CoV-2 transmission. The main aims of the present study were to determine the important clinical, epidemiological, virological and immunological characteristics of first COVID-19 cases in the Netherlands and their household contacts. We wanted to estimate secondary attack rates of SARS-CoV-2 and to determine factors that impact susceptibility and infectiousness, stratified by the age of household contacts. We used a dense sampling strategy with sampling from various anatomical sites and by using several molecular and serological diagnostics methods to determine the presence of the SARS-CoV-2 virus.

Secondary attack rates of SARS-CoV-2 will differ when stratified for the age of the index case.

T1: Home visit within 24 hours after positive test of index case. At this time point we collect questionnaire, serum, naso- and oropharyngeal swabs, saliva and feces.
T2: Home visit 2-3 weeks after inclusion. Data that are collected include questionnaire, serum, swabs, saliva and feces.
T3: Home visit 4-6 weeks after inclusion. Collection of questionnaire, serum, saliva and feces.
T4: Self sampling 6 months after inclusion. Serum by self-sampling (finger prick) and questionnaire.
T5: home visit 9-10 months after inclusion. To collect questionnaire, serum and saliva samples.

Not applicable