Egészségbiztonság Nemzeti Laboratórium(RRF-2.3.1-21-2022-00006) Támogató: NKFIH
Vaccine hesitancy is an inevitable risk for societies as it contributes to outbreaks
of diseases. Prior research suggests that vaccination decisions of individuals tend
to spread within social networks, resulting in a tendency to vaccination homophily.
The clustering of individuals resistant to vaccination can substantially make the
threshold necessary to achieve herd immunity harder to reach. In this study, we examined
the extent of vaccination homophily among social contacts and its association with
vaccine uptake during the COVID-19 pandemic in Hungary using a contact diary approach
in two cross-sectional surveys. The results indicate strong clustering among both
vaccinated and unvaccinated groups. The most powerful predictor of vaccine uptake
was the perceived vaccination rate within the egos’ social contact network. Vaccination
homophily and the role of the interpersonal contact network in vaccine uptake were
particularly pronounced in the networks of close relationships, including family,
kinship, and strong social ties of the ego. Our findings have important implications
for understanding COVID-19 spread dynamics by showing that the strong clustering of
unvaccinated individuals posed a great risk in preventing the spread of the disease.