KEY ISSUES

• HIV transmission among injection drug users (IDUs) is continuing to increase at an alarming rate.
• The dual problem of injection drug use and HIV infection affect those who are most socially and economically disadvantaged.
• Needle and syringe sharing among people who use injection drugs is a major vehicle for the spread of HIV.
• Another factor affecting the spread of HIV is impaired judgment or heightened sex drive due to drug use.

People who use injection drugs account for a significant number of HIV infections in Canada. According to the Laboratory Centre for Disease Control, in 1996, approximately half of the 3000 to 5000 HIV infections that occurred in Canada were among injection drug users.

It's not that street drugs trigger the disease. No matter what other health concerns heroin or cocaine or steroids may raise, they are not directly related to HIV or AIDS.

And it's not that injections themselves cause the problem. Neither a diabetic who needs a dose of insulin or a child who needs a vaccination are at risk. The needles they use are both sterile and safe.

But it's a different story for many injection drug users. And it's their injection equipment that plays the key role.

When people inject drugs, some blood is pulled back into the needle and syringe. If the equipment is shared, that blood is then shot into the bloodstream of the next person in line. If someone infected is taking a turn, the virus will likely be passed on.

Traditionally, when injection drugs were discussed, the focus was on heroin. However, in many cities, cocaine has become the drug of choice. This shift brings with it a new set of problems. Not only does cocaine attract a broader range of users, but people who use cocaine tend to inject far more frequently, increasing both health and safety concerns.

Another factor affecting the spread of HIV is the carelessness that goes along with getting high. When that happens, it's easy to forget any good intentions or plans to use a condom. And that's critical, because unsafe sex is the leading cause of HIV infection. The picture is further complicated - at least for researchers - by the fact that many sex trade workers also use injection drugs. If they or their partners contract the disease, was it through sex? Or sharing drug injection equipment?

The situation is serious. In 1997, 19% of adult cases diagnosed in Canada were transmitted through injection drug use. In Montreal alone, experts estimate there 4-9 new infections per 100 users per year. In Vancouver, prevalence among injection drug users increased from 4% in 1992/1993 to 23% in 1996/1997.

There is no cure yet for HIV infection, but it can be prevented. Drug users can stop using drugs altogether - addiction treatment programs can succeed - or they can learn safer methods of injecting them. The safest way is to use either sterilized needles or brand new ones.

That's why many centres have started needle exchange programs where old needles can be turned in for new ones. The cost of providing clean needles is small compared to the human and economic cost of treating people with HIV or AIDS.

With a ready supply of fresh water and bleach, it's also possible to sterilize previously used needles and syringes. But drug users are best protected when they have their own clean equipment and don't share.

Experts estimate that each case of HIV that progresses to AIDS means about $100,000 in direct medical care, while the economic cost, based on the loss of a lifetime of earnings, could be as high as $650,000 per person. With estimates that high, investing in the prevention of HIV infection is sound public policy.

Recent data indicate that HIV transmission among injection drug users (IDUs) is continuing to increase at an alarming rate, and is not confined to Canada's major urban areas. Further, the dual problem of injection drug use and HIV infection affect the most socially and economically disadvantaged persons in our society: the inner city poor, Aboriginal peoples, and women.

Consider the following:

• As of December 31, 1997, 15, 500 AIDS cases had been reported to the Bureau of HIV/AIDS and STD. Of these 725 (4.7%) were attributed to injection drug use and an additional 681 (4.4%) were attributed to the combined category of injection drug use and MSM (men who have sex with men).
• Injection drug use is more common risk factor for women with 19.2% of adult female AIDS cases attributed to injection drug user versus 3.9% for adult male cases.
• Unlike the overall AIDS epidemic where the annual number of AIDS cases has levelled, the number of cases attributed to IDU alone has risen steadily over time.
• The proportion of AIDS cases attributed to injection drug user has also increased over time. For adult male cases, this proportion has increased from 0.7% during the period before 1988, to 2.4% during 1988-1992, and to 6.5% during 1993-1997. For women, the increase has been even more dramatic: from 4.1% to 14.7% and finally to 24.9% for the respective time periods.
• HIV prevalence and incidence data suggest urgent problems among injection drug users.
• HIV prevalence among injection drug users in Montreal has increased from about 5% prior to 1988 to a documented average of approximately 10% in 1996.*
• Prevalence in IDUs in Toronto is approximately 5% (1996).*
• In Vancouver, the documented average among IDUs is approximately 15%. One Vancouver study of high risk IDUs documented a rate of 23%, which is one of the highest rates in North America.*
• In Ottawa-Carleton, as of July 1, 1998, of the 1741 HIV infections reported, approximately 17% were attributed to injection drug use.
• Sub-populations within the IDU community require special attention.
• Injection drug users are over-represented in prisons. Estimates of HIV prevalence among prisoners vary from 1-4% in men and from 1-10% in women, and in both groups infection is strongly associated with a history of injection drug use.