Article in the New York Times cite studies by Holly Hagan and Don Des Jarlais showing that syringe exchange programs work in preventing HIV and hepatitis C.
The article cites the following publications:
Hagan H, Des Jarlais DC, Friedman SR, Purchase D, Alter MJ (1995).
Reduced risk of Hepatitis B and Hepatitis C among injecting drug users participating in the Tacoma Syringe-Exchange Program.
American Journal of Public Health, 85 (11), 1531-1537. doi: 10.2105/AJPH.85.11.1531.
Des Jarlais DC, Marmor M, Paone D, Titus S, Shi Q, Perlis TE, Jose B, Friedman SR (1996).
HIV incidence among injecting drug users in New York City syringe-exchange programmes.
Lancet, 348 (9033), 987-991. doi: 10.1016/S0140-6736(96)02536-6.
Nguyen TQ, Weir BW, Des Jarlais DC, Pinkerton SD, Holtgrave DR (2014).
Syringe exchange in the United States: A national level economic evaluation of hypothetical increases in investment.
AIDS and Behavior, 18 (11), 2144-2155. doi: 10.1007/s10461-014-0789-9.