According to the new study, a vaccinated adult is more than ten times less likely to infect their household members than an unvaccinated individual.
Sheba Medical Center and Sorbonne University joined forces to conduct the first study examining the effect of vaccination and isolation on the risks of infection and transmission in households.
The study confirmed the high efficacy of the Pfizer-BioNTech vaccination in reducing infection and transmission of COVID-19 and suggests that isolation precautions also mitigate the risk of infection, and should be implemented whenever a household member is infected.
The study participants were Sheba Medical Center employees and their family members, totaling 902 people, including 215 persons with a confirmed COVID-19 diagnosis. Household members underwent a PCR test upon recruitment to the study and followed up with repeated PCR tests for a minimum of ten days after infection confirmation.
In households where an adult member was exposed to a confirmed COVID-19 patient, the study showed that vaccination reduces the risk of COVID-19 transmission to other household members from 54% to 4%. When contacts were not vaccinated, isolation also led to significant reductions in the risk of transmission.