HCV rates outpacing HIV in NYC, study finds
New IDUs had greatest HCV burden
New research in New York City shows that injection drug users (IDUs) are acquiring hepatitis C (HCV) at a faster rate than HIV.
Investigators looked for a correlation between HCV and HIV among IDUs in the Bronx, Harlem, and other areas, and were surprised to find that where there were high HCV rates, there were not necessarily high HIV rates.
"The most important thing was that the duration of injection was most predictive of hepatitis C prevalence," says Crystal Fuller, PhD, infectious disease epidemiologist at the center for urban epidemiologic studies at the New York Academy of Medicine and an assistant professor at Columbia University’s Mailman School of Public Health in New York City.
"People who had recently started injecting had the most HCV burden," she says. "We saw a very high HCV prevalence at about 61%, and we also saw a low HIV prevalence among our population, which was 5.4%.
"Those two pieces of information coupled together, we think, suggest IDUs are not acquiring HIV as rapidly as hepatitis C," Fuller adds.
"And lastly, this lack of association we saw between neighborhood-level HIV and HCV rates and IDUs provides us with more evidence of sexual transmission of HIV among IDUs than drug-related transmission," she notes.
HCV developing first
Researchers didn’t see much evidence of coinfection, but where it existed, it was clear that the HCV infection occurred first and that the HIV infection probably came from sexual transmission, she says.
The study’s findings suggest that the epidemic has changed, Fuller explains. "The rates of HIV have been going down among drug users for some time now." The study concludes that the dynamics of HIV and HCV transmission may vary by neighborhood.1
She notes a number of possibilities for these findings. "First of all, the rates of HIV have gone down, so you don’t have the same HIV burden in the community as we used to have in the late 1980’s and early 1990’s," Fuller says. "Even if you share a needle a few times, you’re not as likely to share the needle with someone who has contaminated the syringe with HIV."
The other issue is that HIV is not as efficient a virus as is HCV, which is why investigators saw high rates of HCV infection among new IDUs, she says.
Syringe exchange programs may play an important role in the lower HIV transmission rates among IDUs, Fuller explains.
Although the study did not specifically examine needle exchange use, the initial analysis found that the overall rate of syringe exchange use is about 35%, she says.
"People have time to access syringe exchange in time to prevent HIV infection," Fuller notes. "With hepatitis C, if you don’t have access to clean needles from the start, you’re in trouble."
With credit going to IDU and HIV prevention strategies, there’s been measurable success in lowering HIV rates, but those same strategies have not had an impact on HCV transmission, she says.
Getting help early
"It comes down to the fact that people need to access services early," Fuller says. "It takes new injectors a while to access prevention services, and because they’re not immediately identified as an injector, they’re hidden and much harder to locate by outreach workers."
Future prevention strategies should focus on the very beginning of the cycle in which a noninjection drug user becomes an injection drug user, she suggests.
"We’ve talked about this issue of reaching people earlier and preventing them from injecting in the first place," Fuller says. "Then the second thing we can do is to try to reach those who’ve recently started injecting."
Fuller is involved in research that will use social network-based strategies, such as a peer network model, to reach people and convince them to share information with their friends and people with whom they hang out, she says.
"In addition to that, we have to find viable information about accessing sterile syringes," Fuller says. "It’s possible they may choose to go to pharmacies to acquire needles because in 2001, New York passed a public health law to allow syringes to be sold without a prescription to anyone over age 18."
Interestingly, researchers found that younger IDUs were using pharmacies more than older people, she points out. "In a pharmacy, there’s no way anyone can identify you as an injector because you could be a diabetic," Fuller adds. "It’s cheaper than buying needles on the street, and pharmacies can sell a person up to 10 syringes at a time."
1. Nash D, Fuller C, Blaney S, et al. The relationship between neighborhood HIV prevalence and other neighborhood level indicators to prevalence in a sample of recently initiated injecting drug users in New York City. eJIAS 2004. Abstract: WePeC6046.