Vaccine effectiveness against SARS-CoV-2 transmission and infections among household and other close contacts of confirmed cases, the Netherlands, February to May 2021
Brechje de Gier, Stijn P. Andeweg, Rosa Joosten, Ronald ter Schegget, Naomi Smorenburg, Jan van de Kassteele, RIVM COVID-19 surveillance and epidemiology team 1,, Susan Hahné, Susan van den Hof, Hester E. de Melker, Mirjam J. Knol
Abstract
Several studies report high effectiveness of COVID-19 vaccines against SARS-CoV-2 infection and severe disease, however an important knowledge gap is the vaccine effectiveness against transmission (VET). We present estimates of the VET to household and other close contacts in the Netherlands, from February to May 2021, using contact monitoring data. The secondary attack rate among household contacts was lower for fully vaccinated than unvaccinated index cases (11% vs 31%), with an adjusted VET of 71% (95% confidence interval: 63-77).