A new global study wants men included in human papillomavirus (HPV) vaccination programmes, which currently target young women.

This plea follows an analysis of the global prevalence of HPV infection in males aged 15 years and older.

In a study in The Lancet Global Health, the researchers report that one in three men worldwide is infected with at least one type of HPV. Of these, one in five men have one or more high-risk or potentially carcinogenic HPV types.

“Our results show that HPV prevalence is high in men over 15 years of age and support that sexually active men, regardless of age, are an important reservoir of HPV genital infection,” the Lancet study said.

The study shows that HPV prevalence peaks in men between the ages of 25 and 29 and remains high until the age of 50.

Younger males aged 15 and 19, most of whom become infected after their first sexual encounter, also have high infection rates.

Read: Lancet backs HPV vaccination for boys

“These estimates underscore the importance of including men in comprehensive HPV prevention strategies to reduce HPV-related morbidity and mortality in men and ultimately achieve elimination of cervical cancer and other HPV-related diseases,” the study says.

According to the World Health Organisation, at least 13 of the more than 100 sub-types of HPV can cause cancer, of which cervical cancer is the most common and is caused by two main HPV variants.

Prioritisation

In 2006, the US Food and Drug Administration approved the first HPV vaccine, which can prevent infection with about four HPV strains, including those that cause cervical cancer.

It took 13 years after approval for Kenya to publicly introduce its first doses of HPV vaccine, with support from Gavi, the Vaccine Alliance. As of 2019, young Kenyan girls aged between nine and 14 will continue to receive free HPV vaccines at school.

The vaccine is given in two doses over a period of six to 12 months. Data from the Ministry of Health shows that around 58 per cent of girls in 2022 have received the first dose and a further 32 per cent have received the second dose.

But boys are still being left out. Earlier this year, Dr Mary Nyangasi, Head of the National Cancer Control Programme in Kenya, considered casting the HPV vaccination net wider to include boys.

Read: In Kenya, HPV vaccine to be rolled out next year

As of last year, only 45 countries were vaccinating their boys against the HPV.

According to Dr Nyangasi, if vaccinated, males will be able to clear the infection since they are considered reservoirs of the HPV virus.

“Vaccines work by boosting your immunity. When you are vaccinated, your immunity is alerted so that if you get an infection in the future, you will be able to fight it off,” she added.

She said there are different types of HPV-related cancers, some of which affect men and others affect women.

In Kenya, the Gardasil HPV vaccine is the only licensed HPV vaccine recommended for boys.

“One of the things we should know is that the demand for HPV vaccine is high worldwide, but the supply is low. So, when it comes to public health, we have to prioritise according to the risk factors of the population,” she added. Dr Nyangasi stressed that the available HPV vaccines are safe, useful and important.

“If young girls take them, we could have a generation with few or no cases of cervical cancer,” she said. A study conducted by the Kenya Medical Research Institute, which is currently being reviewed by the WHO, shows that in the future, a single dose could be effective in preventing HPV infection.