Question to the Department of Health and Social Care:

To ask Her Majesty's Government what assessment they have made of the difference in protection against COVID-19 provided by (1) vaccination, and (2) antibodies, following a COVID-19 infection.

Multiple studies on the immune protection provided by both COVID-19 vaccination and natural immunity following infection are underway. This includes the SARS-CoV-2 Immunity and Reinfection EvaluatioN (SIREN), the Office of National Statistics COVID-19 Infection Survey, Vivaldi, and the REal-time Assessment of Community Transmission studies. Findings from these studies show that both infection-acquired and vaccine-acquired immunity give high levels of protection from new symptomatic and asymptomatic infections for several months.

Results from the SIREN study indicate that vaccination was 85% effective in healthcare workers after two doses, compared to an 84% lower risk of subsequent infection in healthcare workers with natural immunity. The COVID-19 Infection Survey concluded that although vaccines are less effective against the Delta variant compared to Alpha, vaccine-acquired protection remains at least as good as natural immunity. In both people with and without prior natural infection, vaccination provides the highest level of protection.