The Changing Epidemic of HIV

Characteristics of persons with heterosexually acquired HIV infection, United States 1999-2004

OBJECTIVES

In the United States a growing proportion of cases of heterosexually acquired HIV infections occur in women and in persons of color. We analyzed the association between race/ethnicity, whether diagnoses of HIV infection and AIDS were made concurrently, and the survival after diagnosis of heterosexually acquired AIDS.

METHODS

We used data from 29 states that report confidential name-based HIV/AIDS cases to the Centers for Disease Control and Prevention to calculate estimated annual percentage change in the number of actual diagnoses and analyzed the association between race/ethnicity and concurrent diagnoses of HIV and AIDS. We adjusted for reporting delays and absence of information about HIV risk factors.

RESULTS

During 1999 to 2004, diagnoses of heterosexually acquired HIV were made for 52 569 persons in 29 states; 33 554 (64%) were women. Among men and women, 38 470 (73%) were non-Hispanic Black; 7761 (15%), non-Hispanic White; and 5383 (10%), Hispanic. The number of persons with heterosexually acquired HIV significantly increased: 6.1% among Hispanic men (95% confidence interval=2.7, 9.7) and 4.5% among Hispanic women (95% confidence interval=1.8, 7.3). The number significantly decreased (-2.9%) among non-Hispanic Black men. Concurrent HIV and AIDS diagnoses were slightly more common for non-Hispanic Whites (23%) and Hispanics (23%) than for non-Hispanic Blacks (20%).

CONCLUSIONS

To decrease the incidence of heterosexually acquired HIV infections, prevention and education programs should target all persons at risk, especially women, non-Hispanic Blacks, and Hispanics.

HIV incidence in the United States, 1978-1999

CONTEXT

HIV incidence measurements, which reflect recent or current transmission, are valuable for monitoring the epidemic and evaluating prevention programs.

OBJECTIVES

To summarize HIV incidence patterns and trends in U.S. population groups.

DATA SOURCES

Publications in English from 1980 through mid-2000. STUDY SELECTION AND STATISTICAL METHODS: We searched the literature for reports of HIV incidence in the United States. Locally weighted scatterplot smoothing was used to generate smooth curves to estimate trends in incidence. Spearman rank correlation was used to estimate the correlation coefficient between prevalence and incidence.

DATA SYNTHESIS

In 74 eligible reports, HIV incidence varied widely (0.002-19.8 per 100 person-years [py]) depending on risk group. Among men who have sex with men (MSM), HIV incidence peaked in the early 1980s (5-20/100 py) and then declined but remained high during the 1990s (2-4/100 py). Among injection drug users (IDUs), incidence decreased since the mid-1980s but differed by geographic area; in the 1990s, incidence remained high in the East (1-3/100 py) but was lower in the West (<0.5/100 py). Throughout the late 1980s and 1990s, incidence was low and stable in broader populations (blood donors: <0.01/100 py; military personnel: 0.01-0.07/100 py). The correlation between HIV incidence and prevalence was strong in populations with a prevalence less than 1% (r = 0.94, p<.0001), moderate in populations with a prevalence from 1% to less than 10% (r = 0.57, p<.0001), and weak in populations with a prevalence at least 10% (r = 0.23, p=.09).

CONCLUSIONS

HIV prevention in the United States should continue to focus on MSM and IDUs. HIV incidence measurements should be considered for monitoring HIV transmission in MSM, IDUs, and other populations in which seroprevalence is high.