
The human papillomavirus vaccine provides a benefit to women even if they are not vaccinated, via a phenomenon known as herd immunity, a new study suggests.
Among the women in the study, there was a decrease in the percentage who were infected with the four HPV strains included in the vaccine (HPV 6, 11, 16, and 18) in the years after the vaccine was introduced, compared with earlier years.
This decrease in HPV prevalence was seen among both vaccinated and unvaccinated women, the researchers said.
The findings show that even with relatively low rates of women getting vaccinated, the vaccine produces some degree of herd immunity — protection...