- Category: Injection Drug Use
- Published on Friday, 25 October 2013 00:00
- Written by Keith Alcorn
A switch to a cheaper injectable illicit drug led to a major outbreak of HIV infection in Tel Aviv and should serve as a warning signal for other cities with apparently stable HIV epidemics among people who inject drugs, Israeli researchers warned last week at the 14th European AIDS Conference in Brussels.
Michel Kazatchkine, the UN Secretary General’s Special Envoy on HIV in Eastern Europe and Central Asia, also warned the conference of the potential for new epidemics of HIV among people who inject drugs, following recent HIV outbreaks in Romania and Greece driven by the availability of new substances.
HIV prevalence among people who inject drugs in Israel has been stable for the past decade, as a result of government-funded needle and syringe exchange programs, and opioid substitution therapy. Crusaid Kobler AIDS Center of Tel Aviv Sourafsky Medical Center had recently observed no cases of primary HIV infection in people who inject drugs among 130 cases of primary infection diagnosed by the clinic.
Yet in June 2012, Tel Aviv Medical Center Laboratory noticed a disturbing phenomenon: 5 primary HIV infections had been diagnosed in people who inject drugs in 2 months, and over the following year a further 40 cases were identified. The majority of these cases were diagnosed following admission to the hospital with severe bacterial infections -- bacteremia, pneumonia, or endocarditis -- and every person diagnosed with HIV was also found to have hepatitis C. In every case the patient was a long-term heroin injector who had been using the needle and syringe exchange on a regular basis.
But in early 2012, a large number of heroin injectors began switching to a cheaper injectable substance, known as "hagitat" in Israel, a cathinone derivative also known as "bath salts," injected in combination with the opioid substitute buprenorphine.
Cathinone derivatives are synthetic amphetamine-like stimulants that induce euphoria, increased sex drive and sociability, as well as delirium and violent, erratic behavior. They can also cause cardiac arrhythmias, hyperthermia, rhabdomylosis, or death, and are associated with a high frequency of severe bacterial infections if injected. Cathinone derivatives include mephedrone, a popular club drug. Many synthetic cathinones are not controlled substances under drug enforcement legislation and new variants are emerging all the time.
Everyone who became infected with HIV during the 2012-2013 Tel Aviv outbreak had switched to injecting hagitat. In contrast, none of the stable drug users who continued to inject heroin became infected with HIV.
Cathinone derivatives were adopted rapidly by drug users in Tel Aviv because they are cheap in comparison to heroin, but the drug effect is short, requiring up to 30 injections each day. Whereas heroin injecting is a relatively private activity (needle sharing takes place with only 1 or 2 people in most cases), cathinone injecting tends to be highly social.
Furthermore, whereas heroin injecting requires the drug to be heated in a cup or spoon before being drawn up into the syringe, cathinone derivatives must be dissolved in cold water to avoid inactivating the drug. This is likely to remove any sterilizing effect that heating might have during heroin injecting, said Eugene Katchman from Tel Aviv Sourafsky Medical Center. A very high rate of syringe re-use and needle sharing occurs as a result of the high injecting frequency, he added.
Phylogenetic analysis of 30 outbreak isolates revealed that all drug users had been infected with HIV-1 subtype A/CRF01 AE, and suggested that all infections were linked to one originating isolate.
In an effort to limit the further spread of HIV, doctors from Tel Aviv Sourafsky Medical Center educated needle and syringe exchange program staff and volunteers on the outbreak, and instituted an active screening program among drug injectors who used the needle and syringe exchange.
Needle and syringe exchange staff launched an education program among drug users, and also increased the supply of needles, syringes, and sterile cups.
Everyone who tested positive for HIV was offered immediate antiretroviral treatment in order to reduce viral load and limit onward spread of HIV. Viral loads at diagnosis were high (a median of 181,000 copies/mL) and the median CD4 cell count was 560 cells/mm3.
A rapid, multidisciplinary response is required when shifts in drug use trigger a new outbreak of HIV among people who inject drugs, Katchman told the conference.
E Katchman, M Savyon, D Chemtob, et al. An outbreak of primary HIV infection among injecting drug users in Tel Aviv, Israel, associated with changes in illicit drug use practices. 14th European AIDS Conference (EACS 2013). Brussels. October 16-19, 2013. Abstract PS11/14.