A single dose of either the Pfizer/BioNTech or the AstraZeneca/Oxford COVID-19 vaccines reduced household transmission by up to a half.

A single dose of either the Pfizer/BioNTech or the AstraZeneca/Oxford COVID-19 vaccines reduced household transmission by up to a half, according to new research by Public Health England (PHE). The study, published as a preprint, found that those who become infected 3 weeks after receiving a first dose of the Pfizer/BioNTech or AstraZeneca/Oxford vaccines were between 38% and 49% less likely to pass the virus on to household contacts than those who were unvaccinated. Protection was seen from around 14 days after vaccination, with similar levels of protection across all age groups. PHE added that this protection was on top of the reduced risk of a vaccinated person developing symptomatic infection from SARS-CoV-2 in the first place, which was around 60% to 65% - 4 weeks after one dose of either vaccine. See-"Impact of vaccination on household transmission of SARS-COV-2 in England"- Ross J Harris; Jennifer A Hall; Asad Zaidi; Nick J Andrews; J Kevin Dunbar; Gavin Dabrera.