Use of syringe exchange and distribution services has increased substantially over the past decade in the United States, and HIV diagnoses among people who inject drugs have fallen by nearly half, but just a quarter of drug injectors use only sterile needles and a third reported sharing a needle within the past year, according to the latest Vital Signs report from the US Centers for Disease Control and Prevention (CDC).
Sharing needles, syringes and other equipment to inject drugs is among the most efficient ways to transmit HIV, hepatitis B virus (HBV) and hepatitis C virus (HCV). Research shows that needle exchange and sterile syringe distribution are effective harm reduction strategies, both reducing infection risk and helping link people who inject drugs to other services. But syringe programmes remain controversial due to concerns about promoting drug use or encouraging crime.
People who inject drugs account for about 9% of all HIV infections diagnosed in the US each year. Since the early 1990s HIV diagnoses among people who inject drugs have decreased dramatically, largely due to greater awareness and harm reduction interventions. However, the ongoing opioid and heroin epidemics in largely white, rural areas of the US have put a new population of injectors at increased risk for HIV and viral hepatitis. In 2015 nearly 200 people in rural Scott County, Indiana, were infected with HIV related to injection drug use.
Syringe service programmes (SSPs) could greatly reduce infection risk if they are implemented widely enough and have enough resources to meet everyone's needs. Since the early years of the HIV epidemic these programmes have largely been established in hard-hit cities, and less so in rural and suburban areas that are bearing the brunt of the recent opioid epidemics.
"The prescription opioid and heroin epidemics are devastating families and communities throughout the nation, and the potential for new HIV outbreaks is of growing concern," said CDC director Dr Tom Frieden. "Our goal is for people to live long enough to stop substance use and not contract HIV or other serious infections while injecting - SSPs can help people accomplish both."
The latest Vital Signs report, published in the 29 November online edition of CDC's Morbidity and Mortality Weekly Report, shows that while use of SSPs has expanded over the past ten years, improved access is still needed as a majority of people who inject drugs use unsterile or shared needles at least some of the time.
Cyprian Wejnert of the CDC's National Center for HIV/AIDS, Viral Hepatitis, STD and TB Prevention and colleagues used data from the CDC’s National HIV Surveillance System from 50 states and Washington, DC, to obtain the number of people who inject drugs diagnosed with HIV from 2008 to 2014.
The researchers also analysed National HIV Behavioral Surveillance interviews of people who inject drugs in 22 US cities to assess risk behaviours and use of prevention services, both among all injection drug users and among new injectors who started injecting within the previous five years.
Between 2008 and 2014, HIV diagnoses among people who inject drugs decreased in urban and non-urban areas, but this decline has levelled off in recent years. Nationwide, HIV diagnoses among people who inject drugs declined by 48% overall, by 50% among blacks and Latinos, and by just 28% among whites.
Among people who inject drugs interviewed in 2015, more than half (54%) said they had used a syringe service programme during the past year, compared to 36% in 2005. However, just 25% reported that they used only sterile needles all the time. A third reported in 2015 that they had shared a syringe within the past year, about the same as the percentage who did so in 2005.
About 46% of white new drug injectors said they shared syringes, compared with 32% of Latinos and 28% of black people. Syringe sharing between 2005 and 2015 decreased by 34% among African Americans and by 12% among Latinos, but remained unchanged among white people.
The racial/ethnic composition of new drug injectors changed between 2005 and 2015, with the percentage of black people falling from 38% to 19%, Latinos remaining stable and white people rising from 38% to 54%. Among new injectors interviewed in 2015, white people reported riskier injection behaviours than black people, with 43% reporting needle sharing in 2005 – about the same as the 45% who did so in 2005.
Trends in protective behaviour might explain why HIV diagnoses have declined more among black people than among white people, the study authors commented. Fewer black people are injecting drugs now than before, the proportion of new injectors who are black has decreased by 51% and the percentage of black injectors who share syringes has declined, while the percentage of white new injectors has increased by 40% and syringe sharing remains common. Nevertheless, black people remain at increased risk for HIV compared to other racial/ethnic groups due to higher prevalence of HIV in their communities.
"Reducing syringe sharing through improved access to SSPs is a critical component of HIV prevention among people who inject drugs," the researchers wrote. "Although access to syringes from SSPs has increased, the supply of sterile syringes available to most people who inject drugs is likely to be insufficient to meet their needs, and barriers remain to accessing SSPs, including lack of SSPs in rural areas and absence of legal support in many states."
Decisions about syringe programme implementation are made at state and local levels in the US, and access varies widely. The CDC has historically recommended that states ensure that people who inject drugs have access to effective prevention services, including sterile injection equipment, medication-assisted treatment using methadone or buprenorphine for substance use disorders, and HIV and hepatitis testing.
In December 2015 Congress allowed states and local communities to use federal funds to support certain components of comprehensive SSPs, not including purchasing syringes themselves. Public health workers and advocates are now concerned that progress in implementing SSPs and other harm reduction efforts may be reversed under a more conservative Donald Trump administration.
"The window of opportunity for implementing SSPs that provide comprehensive services to prevent, rather than respond to, HIV outbreaks might be closing," the researchers concluded. "Swift action can lead to further decreases in HIV diagnoses and prevent new outbreaks among people who inject drugs."
"CDC’s ground-breaking report reaffirms that syringe exchange works, but we don’t have enough programs," Harm Reduction Coalition policy director Daniel Raymond said in a press release. "Since the Indiana HIV outbreak, the policy landscape for syringe exchange has shifted dramatically. For communities on the frontlines of the opioid and heroin crisis, the pressing questions about syringe exchange are no longer whether to implement them, but how quickly they can scale up."
Wejnert C et al. Vital Signs: Trends in HIV Diagnoses, Risk Behaviors, and Prevention Among Persons Who Inject Drugs – United States. Morbidity and Mortality Weekly Report, 2016.