Some B.C. clinics will utilize a new HIV test after a study found it detects the disease more quickly after it enters the body, reducing the likelihood the virus will spread.
The study, conducted by the B.C. Centre for Disease Control and published this week in the AIDS Journal, determined the test detects the virus within one to two weeks after the person contracts the infection, while standard testing can take up to four weeks.
Mark Gilbert, the study's co-author and a physician epidemiologist of sexually transmitted infections at BCCDC, said early detection is important because people who've just acquired the virus are at greater risk of transmitting it to others.
"We know that if people have a diagnosis of HIV they change their behaviour, they access treatment, and so being able to really increase the capacity to diagnose acute infection … has a potential to decrease transmission and prevent new HIV infections," he said in an interview Wednesday.
The study said nucleic acid amplification testing was used at six Vancouver clinics accessed by gay and bisexual men. The pilot program began in April, 2009.
The study said 25 men who would have received a negative result under the standard test were found to have the virus under the nucleic acid test. Between 25 and 75 new infections were avoided, the study said, because those who tested positive quickly sought treatment and changed their behaviour.
The testing will continue at the six Vancouver facilities and will be used at other clinics throughout the province, though how many and where remains unclear.
Mel Krajden, also a study co-author and associate medical director at the B.C. Public Health Microbiology and Reference Laboratory, said early detection means lower health-care system costs.
"Every single transmission you avoid, the lifetime cost of treating HIV is about $300,000. So by making an upfront investment in a highly targeted diagnostic, you get a substantial health outcome gain and cost reduction," Dr. Krajden said in an interview.
B.C. is the first province in Canada to use the new test. Dr. Gilbert said it has been utilized in some U.S. jurisdictions. He said discussions must still be held on exactly which clinics will have such testing available. Dr. Krajden said the focus will continue to be clinics that are accessed by gay or bisexual men.
"It costs about $10 per person to do the test and, statistically, the yield is greatest when you have a population that is at high risk of being infected. So if you roll it out to everybody, you're spending an extra $10 and your yield … would be substantially lower," he said. "It's really trying to obtain the most benefit at a reasonable cost."
Terry Lake, B.C.'s Minister of Health, wrote in a statement that the province is "committed to reducing the spread of HIV by ensuring those living with HIV/AIDS have access to the best care and treatment." He said it is "very exciting that this ground-breaking research is going on right here in B.C."
There were 238 cases of HIV diagnosed in B.C. last year, compared to the peak of 929 cases in 1987. More than 60 per cent of those diagnosed last year were gay or bisexual men.
Wayne Robert, executive director of the Health Initiative for Men and another study co-author, said it's important to let gay and bisexual men know what resources are available.
"Having enough knowledge to come to another place that offers the earlier test, for them to be able to incorporate that into their health regime, is we thought one of the powerful messages," he said in an interview.