A significant reduction in four vaccine-preventable human papillomavirus (HPV) strains was seen after a vaccine program that targeted young gay and bisexual men between 16 and 20 years old.

The study, called HYPER2 and led by Eric Chow of Monash University along with Alfred Health, saw up to 70% reduction in one type of HPV in gay and bisexual men after the school-based program was introduced in 2013.

Australia is the first – and one of only a few – countries to have HPV vaccinations for both boys and girls. There are four different strains of HPV, and symptoms include genital warts and cervical and anal cancer.

Anal cancer has been increasing in prevalence and is overrepresented among gay and bisexual men.

The study included 400 school-aged students who identified as homosexual or bisexual. It found that strains associated with anal cancer dropped from 28% prevalence to 7.3%, and strains associated with penile cancer dropped from 11.9% to 6.1%.

“Australia has a very successful HPV vaccination program for both boys and girls with high vaccine coverage,” says Chow.

“The vaccine is effective in reducing HPV-related diseases and showing some promising evidence that this may lead to a reduction in HPV-related cancer in the future.”

The vaccine targets all four strains of HPV – this type of vaccine is called quadrivalent. The full study was published in The Lancet Infectious Diseases.

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