1. Magnani R, Sabin K, Saidel T, Heckathorn D. Review of sampling hard-to-reach and hidden populations for HIV surveillance. AIDS. 2005;19(Suppl 2):S67–72.
2. Rudd RA, Paulozzi LJ, Bauer MJ, et al. Increases in heroin overdose deaths—28 States, 2010 to 2012. MMWR Morb Mortal Wkly Rep. 2014;63(39):849–54.
3. Suryaprasad AG, White JZ, Xu F, et al. Emerging epidemic of hepatitis C virus infections among young non-urban persons who inject drugs in the United States, 2006–2012. Clin Infect Dis. 2014;59(10):1411–9.
4. Conrad C, Bradley HM, Broz D, et al. Community outbreak of HIV infection linked to injection drug use of Oxymorphone—Indiana, 2015. MMWR Morb Mortal Wkly Rep. 2015;64(16):443–4.
5. Stanley MM, Guilfoyle S, Vergeront JM. Hepatitis C virus infections among young adults—rural Wisconsin, 2010. Morbid Mortal Wkly Rep MMWR. 2012;61(19):358.