B.C. is the only province where the rate of new HIV infections is falling steadily and markedly. B.C. is also the only province that offers highly active anti-retroviral therapy (HAART) free of charge and aggressively promotes its use.
Coincidence? Not at all.
New research published in Wednesday's edition of the medical journal Public Library of Science One shows that for every 10-per-cent increase in the number of HIV-positive patients taking HAART, new HIV diagnoses fell 8 per cent – pretty close to a perfect correlation.
These are some of the most compelling data to date demonstrating the soundness of the "treatment as prevention" theory, an approach conceived at the B.C. Centre for Excellence in HIV-AIDS and now being embraced worldwide.
Treatment as prevention – or TaP for short, because in the world of HIV-AIDS, acronyms are de rigeur – is so successful, from Zimbabwe to Abbottsford, that policy-makers now talk openly about the possibility of freezing the epidemic in its tracks and creating an AIDS-free generation.
As is too often the case though, Canadians are slow to embrace Canadian innovation.
Consider that a young man diagnosed today as HIV-positive at age 20 and placed on HAART can expect to live to age 73, a life expectancy near normal.
By taking a cocktail of medication that suppresses replication of the virus, this man will have little likelihood of passing it on to his sexual partner(s).
That, of course, is the goal: To stop new infections, in addition to keeping those who are already infected from falling prey to killer opportunistic infections.
Development of an AIDS vaccine is proving to be bedevilling, so TaP remains the closest thing we have. Of course, it is an adjunct, not a replacement for other preventive actions such as use of condoms and harm-reduction measures like supervised drug injection.
Treating HIV-positive pregnant women with HAART is nearly 100-per-cent effective in preventing transmission of the AIDS virus to their babies. In discordant couples – where one partner is infected and the other is not – infection rates fall 95 per cent if the HIV-positive partner takes HAART. But if treatment as prevention is going to be fully effective, it is essential to get as many HIV-positive people as possible on it.
For that to happen, two measures are required : Universal testing and free treatment.
In the world, B.C. is the jurisdiction that is closest to achieving this goal and it is reaping the rewards. Since the advent of HAART in 1996, AIDS deaths in the province are down 90 per cent and new diagnoses down 65 per cent.
Why isn't every province and territory following B.C.'s lead? Shouldn't an AIDS-free generation be a national goal?
An estimated 65,000 Canadians live with HIV-AIDS. Despite all the prevention efforts, 3,300 new cases are diagnosed annually.
About one in four Canadians who are HIV-positive don't know it, according to the Public Health Agency of Canada, and the unaware are likely responsible for most of the new cases.
At this point, the only way to reduce infections is a "seek and treat" strategy, to use public health jargon.
No one is suggesting that HIV testing be mandatory. But it should be easy and routine. All blood donations in Canada are tested for HIV, and so are pregnant women, but that policy has not extended to all sexually active adults.
Research shows the most effective method is asking every patient who comes into ER, hospital or goes to the doctor: "Do you want to confirm you're HIV-negative?" In a pilot project conducted in Vancouver, 92 per cent of patients answered "Yes." More importantly, six in every 1,000 patients tested turned out to be HIV-positive. According to researchers, a rate of one in 1,000 or higher makes the policy cost-effective.
HAART is expensive – about $10,000 a year in Canada – but it is cheaper than treating people for AIDS. And the more people are treated appropriately, the lower the rate of illness and new infections.
Guidelines call for treatment to begin once an HIV-positive person has a CD4 count of 350 or lower. (CD4 is a measure of the strength of the immune system.) That's roughly half of the infected, although the figure will increase over time as survival increases.
B.C. is treating 45 per cent of the HIV-positive – nearly everyone eligible, but not quite. In Quebec, the rate is 37 per cent, and Ontario 35 per cent. (Among them, the three big provinces account for 86 per cent of all HIV-AIDS cases.) Detailed treatment data are not available for other provinces, but we do know new diagnoses are growing at the fastest rate in Saskatchewan.
Universal testing is not a panacea. But it can and should be the beginning of a cascade of treatment and care.
When we speak of the beginning of the end of AIDS – as scientists now do cautiously – universal "seek and treat" is that beginning.
B.C. is blazing a trail. But others are not following near quickly enough.
André Picard