Sumary of Pfizer vaccine and isolation independently associated with reduced household transmission of SARS-CoV-2:
- With the onset of the coronavirus disease 2019 (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), many parts of the world entered a phase of stringent restrictions through non-pharmaceutical interventions (NPIs).
- These have ranged from social distancing measures to full-scale lockdowns and, while global vaccination efforts are still underway, have been the order of the day to help mitigate the load on healthcare services straining to care for hundreds of seriously ill patients gasping for oxygen.
- Israel was among the leading proponents of COVID-19 vaccination as the way out of the current worldwide restrictions on social and economic interactions and activity.
- A new study, recently released as a preprint on the medRxiv* server, reports on the effects of the large-scale vaccination campaigns carried out in this country, relating to successful control of SARS-CoV-2 spread within households.
- Background Despite the rapid development and unprecedented approval of several COVID-19 vaccines, beginning with the Pfizer BNT-162b2 messenger ribonucleic acid (mRNA) vaccine, the true efficacy of this measure against the virus remains largely unknown.
- The current work was meant to uncover the effect of vaccination on transmission within a household.
- Based on the risk of infection, earlier studies have already shown repeatedly that there was an 80% reduction of viral infection risk after two doses of the BNT-162b2 vaccine.
- This is the first study that examines both vaccination and isolation, as well as age, relative to the risk of infection and household transmission, simultaneously integrating the effects of community infections, tertiary spread in the household, inability to identify the true index case, household size and low infectivity of asymptomatic cases.