Human Papillomavirus Vaccine Shows High EffectivenessBy Miriam Bello | Thu, 04/14/2022 - 07:13
One dose of the Human Papillomavirus (HPV) vaccine offers solid protection against cervical cancer, said the WHO. The protection offered by one dose of the vaccine is comparable to the two or three-dose regimen, found the Strategic Advisory Group of Experts on Immunization (SAGE) after evaluating the evidence that emerged during past years.
Clinical trials have shown that HPV vaccines are highly effective in preventing cervical infection of HPV when given before first exposure to the virus (before individuals begin to engage in sexual activity). HPV vaccines have also been found to reduce infections in other tissues that HPV infects, including the anus and oral region.
Because the cell changes and cancers caused by HPV take years to develop, it has only recently been confirmed that the vaccines reduce the risk of precancers and cancers of the cervix, vagina and vulva as well, explained the US National Cancer Institute.
“The HPV vaccine is highly effective for the prevention of HPV serotypes 16 and 18, which cause 70 percent of cervical cancers,” said Alejandro Cravioto, SAGE Chair to the WHO. “SAGE urges all countries to introduce HPV vaccines and prioritize multi-age cohort catch up of missed and older cohorts of girls. These recommendations will enable more girls and women to be vaccinated and thus prevent them from having cervical cancer and all its consequences over the course of their lifetimes.”
To date, there are three HPV vaccines that protect against HPV types 16 and 18; 9-valent HPV vaccine (Gardasil 9, 9vHPV), quadrivalent HPV vaccine (Gardasil, 4vHPV), and bivalent HPV vaccine (Cervarix, 2vHPV).
SAGE recommends different vaccination processes depending on the patient’s status. The updated vaccine application schedules are:
- One or two-dose schedule for girls aged 9-14.
- One or two-dose schedule for young women aged 15-20.
- Two doses with a 6-month interval for women older than 21.
Mexico began an HPV vaccination campaign in the State of Mexico this month. Following international standards, Governor Alfredo Del Mazo said that campaigns were aimed for girls between 9 and 11 years of age. Del Mazo called on families to participate to prevent cases of cervical cancer, one of the leading causes of death for women worldwide.
In the private sector, the vaccine is sold for MX$3,000 (US$151) at centers such as the Mexican Institute of Human Papillomavirus (IMVPH).