Strains in territory more likely to be cancer causing

Nunavik women are two to three times more likely to be infected with the human papilloma virus than women in southern Canada, a study by medical researchers at McGill University and the University de Montréal has found.

Known as HPV, the virus is passed by sexual contact. The results of infection in women range from genital warts to full-blown cancer of the cervix and uterus.

Nunavik women, and particularly young women who are infected with HPV, are more likely to have the more deadly, cancer-causing strains of the virus. Rates of cervical cancer are five times higher in Nunavik than in southern Canada, said Dr. Paul Brassard, one of the researchers involved in the study.

Researchers looked at the prevalence of HPV in 554 women 15 to 29 in four Ungava Bay communities for their study, published in November's Cancer Epidemiology Biomarkers and Prevention.

They found many women had multiple HPV infections with multiple HPV types. Some infections involved strains that are strongly linked to an increased risk of developing high-grade lesions and invasive cancer.

They also found that older women are vulnerable to reoccurrences of HPV, perhaps due to hormonal changes or lifestyle factors.

This fall, Quebec introduced a province-wide vaccine program against HPV.

Quebec is offering vaccinations to girls and women from nine to 26 against HPV, using $40 million in federal money to pay for the purchase of the vaccine, which costs $600 a dose.

The vaccine offers 100 per cent protection against the development of cervical pre-cancers and genital warts caused by some strains of HPV, with few or no side effects.

Protection offered by the vaccine is expected to last at least four and a half years after the initial vaccination.

Condoms may also lower the risk of HPV infection, but the only sure way to prevent HPV is to avoid all sexual activity, according to the Centres for Disease Control and Prevention.

Brassard said it will take 15 to 20 years to see the results from Quebec's HPV vaccination program.

Brassard also said there's a need for more screening, particularly in women over 40. These women are past their childbearing years and no longer receive routine pap smears during pregnancy, but they are still at risk of HPV infection, his study shows.

Last summer, Brassard started a recruitment program to find women from the Ungava Bay communities in Nunavik for a project to try out self-administered HPV tests. Sponsored by Canadian Cancer Society, the pilot project will see if the self-sampling for HPV is as effective as tests done by nurses.

According to a study on HPV in Nunavut, 26 per cent of Nunavut Inuit women had the high-risk strains of HPV. But the territory has not started a wide-scale vaccination program similar to ­Quebec's.