Vaccines Increased COVID-19 Immunity in Family Members
People without immunity against COVID-19 were also at lower risk of infection and hospitalization as the number of family members with immunity from a previous infection or full vaccination increased. This is shown in a nationwide study performed by researchers at Ume� University, Sweden.
There is a vast body of research showing that vaccines strongly reduce the risk of COVID-19. However, less is known about the influence of vaccination on the transmission of the virus in high-risk environments, such as within families.
‘COVID-19 vaccination is not only for individual protection but also for reducing transmission within families.’
To investigate this, a nationwide, registry-based study was conducted with data of more than 1.8 million individuals from more than 800,000 families. The study is published in JAMA Internal Medicine.
The researcher's combined registry data from the Public Health Agency of Sweden, the National Board of Health and Welfare, and Statistics Sweden, which is the government agency that oversees statistical data.
Researchers quantified the association between the number of family members with immunity against COVID-19 and the risk of infection and hospitalization in nonimmune individuals.
They accounted for differences in age, socioeconomic status, clustering within families, and several diagnoses previously identified as risk factors for COVID-19 in the Swedish population.
They found that there was a dose-response association between the number of immune individuals in each family and the risk of infection and hospitalization in non-immune family members.
The non-immune family members had a 45 to 97 percent lower risk of infection and hospitalization, as the number of immune family members increased.
This finding shows that vaccination helps not only to reduce the individual's risk of becoming infected, but also reduces transmission, which in turn minimizes not only the risk that more people become critically il, but also that new problematic variants emerge and start to take over.
Source: Medindia