Results from a community-randomized trial conducted in Finland in 2007–2014 by scientists from the International Agency for Research on Cancer (IARC) and partners show that compared with girls-only vaccination against human papillomavirus (HPV), gender-neutral vaccination significantly increases the overall protective effectiveness against genital HPV infection in settings with vaccination coverage in women of below about 50%. The improved effectiveness, in particular against HPV types 16, 18, 31, and 33, was attributable to increased herd immunity through the vaccination of boys.
A mathematical modelling exercise based on these results shows that in settings where vaccination coverage in women is only 75%, gender-neutral vaccination can reduce the incidence of infection with HPV type 16, which is the most carcinogenic HPV type and the most difficult type to eradicate, to zero. Infection with other HPV types can also be eradicated through gender-neutral vaccination at even lower vaccination coverage in women.
Because supplies of HPV vaccine are limited, the World Health Organization currently recommends that countries temporarily pause the implementation of gender-neutral HPV vaccination strategies, until the vaccine supply enables equitable access to HPV vaccines by all countries.
Vänskä S, Luostarinen T, Baussano I, Apter D, Eriksson T, Natunen K, et al.
Vaccination with moderate coverage eradicates oncogenic human papillomaviruses if a gender-neutral strategy is applied
J Infect Dis, Published online 11 March 2020;