Offering free treatment for HIV may help reduce the rate of new diagnoses, say B.C. researchers who are calling for the strategy to be used across Canada.

Dr. Julio Montaner of the B.C. Centre for Excellence in HIV/AIDS and fellow researchers believe HIV cases have been averted in B.C. due to expanded coverage for antiretroviral therapy, known as HAART, a cocktail of drugs.

"Except for British Columbia, the number of new HIV diagnoses per year has remained relatively stable over the study period," Montaner's team concluded in Tuesday's issue of the journal PloS One, published by the Public Library of Science.

"The decline in the rate of new HIV diagnoses per year may be in part attributed to the greater expansion of HAART coverage in this province."

The researchers estimated that for each 10 per cent increase in HAART coverage, the rate of new HIV diagnoses decreased by eight per cent.

Dr. Julio Montaner, director of the British Columbia Centre for Excellence in HIV/AIDS, advocates treatment as prevention. (Darryl Dyck/Canadian Press)

The treatment is free in B.C. Other provinces subsidize it to varying degrees, which the researchers said can lead to varying levels of access based on socioeconomic status.

Except for B.C., the number of new HIV diagnoses per year stayed about the same across Canada over the study period of 1995 to 2008.

The B.C. Centre for Excellence in HIV/AIDS pioneered the HAART treatment as a prevention approach, which uses widespread HIV testing and treatment to those who are medically eligible to reduce HIV levels in a patient’s blood to undetectable levels and reduce the risk of transmission.

The decrease in the province's new HIV diagnoses could range from as little as 2.4 per cent to a high of 13.3 per cent, the researchers said.

They also cautioned that the true incidence can't be calculated because of delayed and undiagnosed HIV infections.

While the researchers counted how many people were on HAART in B.C., they relied on drug sales data for the other provinces, which might not be as accurate.

On Tuesday, federal Health Minister Leona Aglukkaq announced $13 million over five years to support new HIV/AIDS research.

Projects will include an aboriginal HIV and AIDS community-based research collaborative centre; examining the link between HIV and other chronic health issues specifically related to aging and mental health; and examining HIV and aging in HIV-positive women and children.

World AIDS Day is Dec. 1.