STANLEY
IT IS important to realize that most sexually active women acquire a virus called human papilloma virus (HPV) at some stage in their lives. In most cases, the body’s immune system is strong enough to fight it off.
However, of the roughly 100 different strains of HPV that could infect women, quite a few have been known to be feisty and lead to serious complications: strains 16 and 18 could cause about 70 percent of all cases of cancer of the cervix (neck of the womb) while strains 6 and 11 could cause the majority of genital warts.
Cervical cancer is the second most common malignancy among women worldwide, with about 500,000 cases a year.
Main cause
In developing countries like the Philippines, it is the main cause of cancer deaths in women, and around 250,000 women die each year because of it (Philippine cervical cancer incidence rate is 11.7 per 100,000 women).
But the situation is not hopeless, according to University of Cambridge (United Kingdom) Prof. Margaret Stanley who recently visited the country to tell UK’s success in dealing with HPV infection and cases of cervical cancer.
“In a country, where 2,900 women are diagnosed with cervical cancer a year (UK cervical cancer incidence rate is 7.2 per 100,000 women), the government in September 2008 began a routine immunization program for HPV for 12- to 13-year-old girls. The vaccine used at the time was a bivalent (which contains protection against two strains) vaccine which protects against infection with HPV strains 16 and 18,” reported Stanley before participants of the third and concluding leg of “It Can Be Done,” an HPV Summit held at the Sofitel Philippine Plaza Manila in Pasay City.
However after three years of running the program, the UK health authorities in September 2012 switched to MSD’s Gardasil, a quadrivalent HPV vaccine that protects against the two strains of HPV that cause cervical cancer, plus two other strains that cause genital warts.
Figures from the UK Health Protection Agency showed that 75,000 people were diagnosed with genital warts in 2010.
Fight genital warts
“Both vaccines protect against HPV types 16 and 18, which cause more than 70 percent of cervical cancer. However, Gardasil offers a much broader protection as it could deal with HPV types 6 and 11 which cause nearly all genital warts, one of the most common sexually transmitted infections,” Stanley explained.
She shared that UK authorities had weighed up both the cost and clinical benefits before deciding to switch to Gardasil, adding that they have reflected the changes in scientific knowledge that has become available since last time.
The UK Department of Health says 400 deaths a year from cervical cancer will be prevented by the said vaccination program (nearly 1,000 women die from the disease every year)
Stanley related that UK health authorities were encouraged by what happened in Australia. In April 2007, Australia started a national government-funded program to provide HPV vaccine (quadrivalent) to all young women accessing health services.
Prevalence of prevention
“After only four years, the Australian authorities found that among vaccinated women, the prevalence of vaccine-preventable HPV infection had dropped from about 30 percent to 7 percent. Even among unvaccinated women, the rate of infection dropped by about half. This means, vaccines help not only the vaccinated, but also the entire community. I believe this program as well as in the UK could serve as a model here considering its success in both countries,” Stanley said.
Australia was the first country to fund a vaccination program for all women aged 12-26 years. A national surveillance network in Australia was established and identified trends in diagnoses of genital warts from 2004 to 2009.
While cervical cancer only accounts for a small percentage of the total number of women’s cancers, majority of cases occur in midlife rather than old age.
“In the UK, while cervical screening program has been able to half the rate of cervical cancer since the 1980s—precancerous changes in the cervix can be detected preventative treatment given—routine vaccination of girls against HPV have cut rates further,” Stanley said.
While several tests can be used in screening for cervical cancer, the Pap smear (cytology) is the only test that has been used in large populations and that has been shown to reduce cervical cancer incidence and mortality.
“Why is the test and immunization important? HPV does not produce symptoms when you get it so you have no way of telling whether it has been present in your body, unless you have had a smear test which reveals precancerous changes caused by the virus. Once cancer is established, the most common symptom is bleeding between periods or after sex as well as menstrual bleeding, which may also be heavier and last longer than normal,” Stanley warned.
Although HPV can be passed on through sex, it has also been found to be passed on through intimate contact including changing the diapers of babies.