Vol. 58 / No. 21 MMWR 591
In 2006, most new HIV infections in the United States, MR Irizarry, Puerto Rico Dept of Health; J Prejean, Div of HIV/
including among Hispanics, occurred in persons aged 13–29 AIDS Prevention Surveillance and Epidemiology, M Ayala-Perales,
years (7). In contrast, most new HIV infections in Puerto Rico and J Andia, Div of HIV/AIDS Prevention Intervention Research
occurred among persons aged 30–39 years. This age group had and Support, National Center for HIV/AIDS, Viral Hepatitis, STD,
the highest rates of new HIV infection in both Puerto Rico and TB Prevention, CDC.
and the United States; however, the incidence rate in Puerto References
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higher rates in this age group in Puerto Rico might be related reports/2006report/default.htm.
to injection-drug use. Persons commonly begin using non- 2. Karon JM, Song R, Kaplan E, Brookmeyer R, Kaplan EH, Hall
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The findings in this report are subject to at least two limita- 4. Harrison KM, Kajese T, Hall HI, Song R. Risk factor redistribution
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that target populations at greatest risk in Puerto Rico, including
injection-drug users, women who have high-risk heterosexual
contact, men who engage in male-to-male sexual contact, Impact of New WHO Growth
and youths. To address transmission of HIV infection among