The human papillomavirus (HPV) is very common, is easily spread by sexual activity, and up to 50% of all people will be infected at some time in their lives. HPV vaccines protect against either two, four or nine types of HPV
Two doses of the human papillomavirus (HPV) vaccine is sufficient to protect preteens and teens against genital warts, new research suggests.
Investigators at Boston University Medical Center found that two HPV vaccine doses are just as effective as three at preventing genital warts. That's in keeping with the new recommendations from the US Center for Disease Control and Prevention.
The study was published online in the journal Sexually Transmitted Diseases.
The CDC and World Health Organization based the new two-dose schedule primarily on "immunogenicity" results – the vaccine's ability to induce an immune response, said study lead author Dr Rebecca Perkins. "But there was very little research on how effective that recommendation has been," added Perkins, an obstetrician.
"This study validates the new recommendations, and allows us to confidently move forward with the two-dose schedule for the prevention of genital warts," she said in a medical centre news release.
The HPV vaccine is currently recommended for all boys and girls between the ages of nine and 14. HPV is a sexually transmitted virus that can also lead to cervical, vaginal and anal cancers.
Health24 previously reported that HPV can be contracted by skin-to-skin contact during oral, vaginal or anal sex with someone who has HPV. Any sexually active person can acquire HPV.
Focus mainly on genital warts
According to the Public Health Association of South Africa (PHASA) the Medicines Control Council (MCC) of South Africa approved two HPV vaccines, but these vaccines are only effective when used as a prophylaxis when administered before exposure.
Researchers say that since 2007, as more parents have chosen to vaccinate their kids, the incidence of genital warts has dropped significantly.
The new study assessed the prevalence of warts among nearly 400 000 girls. The researchers looked to see whether they'd been vaccinated against HPV, and if so, how many doses they had had.
Beyond the conclusion that two doses were just as protective as three, the study found that both dose regimens offered much more protection against genital warts than a single dose or no vaccine at all.
The study focuses mainly on genital warts, however, so the findings do not speak to additional HPV-related health concerns, such as cervical dysplasia (a precancerous condition) or cancer.
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