The national human papillomavirus (HPV) vaccination scheme in Australia has reduced cases of genital warts by 61%, researchers have found.
Researchers from the University of Sydney looked at more than a million patient encounters in primary care between 2002 and 2012.
The data showed a significant year-on-year reduction in the management rate of genital warts in women aged 15-27 years since the programme started.
SInce the HPV vaccination scheme was introduced in Australia in 2007, the rate of genital wart presentation has fallen from 4.33 per 1,000 encounters to 1.67 per 1,000 encounters.
Australia was one of the first countries to provide the HPV vaccine free to young women. The vaccine protects against two major viral causes of genital warts (HPV 6 and 11) and two major viral causes of cervical cancer (HPV 16 and 18).
Study author Christopher Harrison said: "This is the first study to report the impact of HPV vaccinations on genital warts management in general practice, which is where the majority of cases are treated.
"[The study shows] an excellent result as not only do genital warts cause distress in affected patients, but treatment is at a substantial cost to the health system.
"For all other age-sex groups (who were not covered by the program) there was no significant change in the management rate of genital warts between the pre-program and post-program periods.
"There was also no significant decrease in other sexually transmitted infections over this period, which means that the decrease in genital warts was likely due to the vaccination program, not a change in the women's behaviour."
The UK HPV vaccination programme launched in September 2008 for all 12-13 year old girls and 17-18 year old girls.