Vaccines are effective in preventing HPV infections

A new study on the HPV immunisation programme uses mathematical modelling to estimate that vaccinating only girls can prevent nearly all infections caused by the human papillomaviruses HPV16 and HPV18. The HPV16 and HPV18 viruses cause more than 70 per cent of all cases of cervical cancer. 

One of the scenarios modelled in the study involved vaccinating 80 per cent of girls and no boys. In that scenario, 70 years after the start of HPV vaccinations, HPV16 infections among women were reduced by an average of 93 per cent and HPV18 infections by as much as 98 per cent.

Herd immunity is achieved when a sufficient proportion of the total population has been vaccinated and is immune against a given disease. “HPV infections are reduced more than one might expect based on the vaccination coverage. This is explained by herd immunity, which means that even unvaccinated individuals benefit from vaccinations,” says researcher Simopekka Vänskä from the Department of Vaccines and Immune Protection at the National Institute for Health and Welfare.

Mathematical modelling has been widely used to support decision-making concerning HPV immunisation programmes.

Sources:

• Rokotustieto.fi
• THL (in Finnish)