Since implementing a nationwide human papillomavirus (HPV) vaccination program five years ago for females between the ages of 12 and 26 years, Australia has seen a significant decline in the number of cases of genital warts, according to new research in the journal BMJ.
Among the girls within the age range for the vaccine, Australia saw a 59% decline in genital warts cases – just within the first two years of the start of the program in 2007.
HPV is the cause of 90% of genital wart diagnoses and Australia has given significant protection to males and females by aggressively vaccinating girls.
The investigators labeled this as “herd immunity” – when immunity achieved through a particular portion of the population protects the unvaccinated portion of the population. In this case, the vaccinated women protected the unvaccinated men.
Durig this period, Australia has had a 39% decline in genital wart cases in heterosexual men.
Study author Dr. Basil Donovan, who heads the sexual health program at the Kirby Institute of the University of New South Wales, in Sydney, said:
“All indications are that the program has been an overwhelming success. But we won’t be certain until HPV-related cancers [also] start dropping, the incubation period from HPV infection to HPV-related cancer is typically at least 20 to 30 years.”
Cancers that can develop after infection with HPV include:
To measure the effect of HPV the immunization efforts, the researchers examined data taken from eight separate sexual health service organizations covering the years of 2004 to 2011.
During that time, these medical offices saw 86,000 first-time patients – 9% of whom were diagnosed with genital warts. They then compared the pre-vaccination period of 2004 to 2007 with the vaccination period of 2007 through 2011 and found a surprising drop in genital warts rates.
Among girls under the age of 21, the decline added up to 93%, and among those between ages 21 and 30, there was a decline of 73% seen.
Among heterosexual men below the age of 21, the decline was close to 82%, while among those aged between 21 and 30, genital warts dropped by over 51%.
The authors suggest that how effective efforts in other countries will be to eliminate genital wart rates will depend on the degree of public acceptance concerning HPV immunization schedules.
Donovan points out that there was little opposition to the HPV vaccine in Australia; this is not the case in the USA. Donovan described the efforts there as “fractured” because of the controversy and hesitation to vaccinate young girls.
Just last month, a report published in Pediatrics suggested that many parents fail to take their daughters for the HPV vaccine because of fears about effectiveness and side effects – even though medical professionals assure them the vaccines are safe.
A separate study performed last year also suggested that the HPV vaccine does not increase sexual activity in girls , and is not associated with a higher incidence in STIs.
On the other hand in the UK, where there has not been much debate, Donovan commented, “As the U.K. is achieving vaccine coverage rates at least as high as Australia. I would be certain that they will soon be reporting comparable drops in disease.”
Written by Kelly Fitzgerald