Globally, sex between men and women is by far the most common way of passing on HIV. But a second transmission route drives the epidemic in many, if not most, countries outside Africa. That is transmission among men and women who inject drugs.
Injection of any sort is an even more efficient way of spreading HIV than sexual intercourse. Since injecting drug users are often linked in tight networks and commonly share injecting equipment with other people without cleaning it, HIV can spread very rapidly in these populations. Also, like other sexually active people, people who inject drugs may acquire HIV infection through their sexual partners if they have unprotected sex.
How many people are injecting drug users?
Because injecting drug use is illegal in most countries, it is hard to know exactly how many people inject drugs and how many share their equipment. It is even harder to know how many are infected with HIV. Whilst precise figures may be hard to come by, it is clear that HIV can explode through drug-using populations with remarkable speed and can stabilise at very high levels.
How can these risks be reduced?
In relation to sexual transmission, the main means of risk reduction are similar to those that should be adopted by all sexually active people-namely, the consistent and proper use of condoms, or the avoidance of penetrative sex.
In relation to transmission through the sharing of needles, syringes and other equipment, several options are available. Some of these offer better means of protection than others. In order of efficacy they include:
Stopping injecting drug use
Using sterile needles, syringes and other equipment every time
Not sharing injecting equipment
Cleaning equipment between use
Without doubt, the most effective way of reducing the risk of HIV infection is to give up using drugs, but where this is not possible, changing from injecting to non-injecting drug use can significantly reduce the risk of HIV transmission by non-sexual means. For those who inject opioid drugs such as heroin, this may be achieved through participation in a non-injectable drug substitution programme in which a drug such as methadone is administered orally.
An important way of making clean syringes and needles more readily available is through needle and syringe exchange programmes. These have been shown to be effective in preventing the transmission of HIV, and do not increase the use of illegal drugs. Studies in the Netherlands, Britain, Australia and many other countries have shown that syringe and needle exchange programmes significantly reduce the risk of HIV infection through injecting drug use.
What do syringe and needle exchange schemes involve?
Syringe and needle exchange schemes aim to increase the availability of sterile injecting equipment and removing contaminated syringes from circulation. Some of them also refer injecting drug users to appropriate services. They may also provide information and advice on safer sex, and may distribute condoms for use by injecting drug users and their sexual partners. They also access more marginalised and vulnerable drug using populations. In Belarus, an HIV prevention programme among drug users in Svetlogorsk, which included education about safe injecting and safe sex and which provided clean syringes, seems to have led to far safer behaviour among drug users. The prevention programme also included the distribution of condoms to help reduce HIV transmission from infected drug users to their sex partners.
Such schemes have several benefits. For injecting drug users using such programmes, they decrease the proportion of needles and syringes that are contaminated, reducing the likelihood of HIV transmission. For injecting drug users not using such programmes, they lower the proportion of contaminated needles in circulation, thus lowering the risk of new HIV infections more generally. They also reduce sharing and re-use occasions. The Belarus prevention programme reduced the usage of shared syringes dramatically. In 1997, before the prevention programme started, 92% of those surveyed said they shared syringes. 1999, the percentage dropped precipitously to 35%.
Syringe and needles exchange schemes have also been shown to be cost effective. By preventing infections among programme users, their sex partners and their children, and by avoiding the lifetime costs associated with the treatment and care of such infections, exchange schemes can enable health authorities to make important budgetary savings. The Belarus prevention programme is estimated to have prevented over 2000 cases of HIV infection by its second year of operation. At a cost of around US$0.36 per disposable syringe distributed and around US$29 per infection prevented, this is far below the cost of an AIDS case to a family or a health system.
Do syringe and needle exchange schemes increase drug use?
There is clear evidence that syringe and needle exchange schemes neither increase drug use as a result of providing access to sterile equipment, nor increase the frequency of injection among those using such schemes, or the number of new initiates to injecting drug use.
At least six government-funded studies of HIV infection among drug users in the USA concluded that needle exchange programmes significantly reduce new HIV infections without encouraging drug use. Despite these results, however, federal funding of needle exchange programmes is still prohibited in the USA because of political opposition. In one study it was estimated that failure to implement widespread needle exchange programmes in the USA between 1987 and 1995 will cost the country at least US$244 million in medical care for HIV cases that could have been prevented.
In the US, there is evidence to suggest that syringe and needle exchange schemes report increased referrals to drug treatment services, including those services that aim to help injecting drug users stop injecting. This may have an additional benefit in that as a result of such referral some drug users at least may cease to inject thereby reducing the risk of other kinds of drug-related harm.
Note: This information is cross-posted and slightly adapted from AVERT.org in order to emphasize some aspects refering particulary to Moldova. For more details, visual adds, updated information and primary sources, please visit AVERT.org web page.