New HIV diagnoses (incidence) fell about 9% in the United States from 2011 through 2016, according to the latest surveillance update from the Centers for Disease Control and Prevention (CDC). The rate of 13.5 per 100,000 population in 2011 dropped to 12.3 per 100,000 in 2016. But HIV incidence rose in some groups, including people 25 to 29 years old, Asians, and American Indians. Prevalence of diagnosed HIV jumped by nearly 100,000 from 2011 through 2015.
Every year the CDC analyzes and reports HIV incidence, prevalence and mortality data for all 50 states, Washington, D.C., and six dependent areas. The new analysis covers data from 2011 through 2015 and some preliminary data from 2016. The CDC calculates rates in subgroups defined by sex, age, race/ethnicity, HIV transmission category, HIV disease stage and region. The analysis covers people of all ages, though numbers of children younger than 15 are small.
HIV incidence rose from 2011 through 2016 in a single age group, from 29.9 to 34.8 per 100,000 25- to 29-year-olds. Incidence stayed flat among 20- to 24-year-olds and 30- to 34-year-olds and dropped in every other age group. HIV incidence climbed in three racial/ethnic groups: Asians, American Indians/Alaska Natives, and Hawaiians/Pacific Islanders. The new-infection rate remained stable in Hispanics and fell in whites (5.6 to 5.2 per 100,000), blacks (49.5 to 43.6) and multiracial people (27.7 to 12.9).
Over the study period, numbers of new HIV infections remained stable in men who have sex with men (MSM) while falling in men and adolescents infected heterosexually or while injecting drugs. Among those transmission categories in 2016, male-to-male sexual contact accounted for 26,570 new HIV infections, compared with 3,037 new cases from heterosexual contact and 1,285 from injecting drugs. Among female adults and adolescents, the number of new HIV diagnoses in those infected during sex or while injecting drugs dropped across the study period. HIV incidence fell in the Northeast (from 13.9 to 11.2 per 100,000) and South (from 18.3 to 16.8 per 100,000) and changed little in the Midwest (7.5 per 100,000 in 2016) and West (10.2 per 100,000 in 2016).
From 2011 through 2016, the rate of HIV infections classified as stage 3 (AIDS) waned by about a third from 8.3 to 5.6 per 100,000 population, and the AIDS rate dropped in every age group. Nearly every racial/ethnic group had a declining AIDS rate, with the highest 2016 rate in blacks (21.1 per 100,000, compared with 7.2 in Hispanics, 2.2 in whites, and 1.9 in Asians).
Deaths from any cause in people with HIV infection dwindled steadily over the years, from 5.3 per 100,000 people in 2011 to 4.8 per 100,000 in 2015. From 2011 through 2015, the death rate rose in people 60 years old or older, remained stable in those 55 to 59 and those younger than 19, and fell in every other age group. During the same period, all-cause mortality climbed from 13.7 to 14.6 per 100,000 in multiracial people, fell in blacks, Hispanics, Hawaiian/Pacific Islanders and Asians, and stayed flat in other racial/ethnic groups. In 2015, blacks had the highest death rate of any racial/ethnic group with HIV at 17.5 per 100,000.
From 2011 through 2015, prevalence of diagnosed HIV infection rose consistently from 874,266 annually to 973,846 (280.5 to 303.5 per 100,000). By the end of 2015, people 50 to 54 years old accounted for the largest percentage of diagnosed HIV cases (18%). This group also had the highest HIV rate (767.9 per 100,000), followed by people 45 to 49 (703.6 per 100,000) and people 55 to 59 (603.8 per 100,000). The largest percentage increase in HIV cases involved people 65 or oldera 57% jump from 94.2 per 100,000 in 2011 to 148.0 per 100,000 in 2015. These age-related findings confirm the greying of the HIV population in the United States.
Blacks had the highest diagnosed HIV prevalence by the end of 2015 (1017.8 per 100,000) as well as the greatest percentage of diagnosed cases (42%). In contrast, blacks make up about 13% of the U.S. population. By the end of 2015, HIV prevalence stood at 379.4 per 100,000 in Hispanics, 150.9 in whites, and 74.8 in Asians. At the same point, diagnosed HIV prevalence measured 563.9 per 100,000 in adult and adolescent males, 169.7 in adult and adolescent females, and 4.4 in children younger than 13.
The CDC offers no analysis or comments on their findings. But some of the changes reported reflect results of other population studies in the United States and elsewhere. The overall decline in HIV incidence from 2011 through 2016 can be partly explained by steady expansion of HIV testing in the United States, detailed in a separate CDC report. Increased testing cuts the gap between HIV infection and diagnosis and thereby limits the time HIV-positive people may unknowingly expose partners to the virus.
This nationwide analysis spotlights certain demographic groups that do not share overall improvements in the new HIV diagnosis rate -- notably 20- to 34-year-olds, MSM, and Asians, American Indians, and Hawaiian natives. A separate CDC study found rising HIV testing rates in MSM, which probably blunted new HIV diagnoses in this group and resulted in stable (though high) HIV incidence in recent years. But young people had HIV testing frequencies similar to those of older groups in this analysis, so limited testing does not explain their persistently higher HIV incidence.
A climb in the total number of people living with HIV reflects prolonged survival of people with HIV worldwide. One multicohort analysis figured that 20-year-olds with HIV in the United States and Canada can expect to live into their 70s, a life expectancy approaching that in the general population.
Mark Mascolini writes about HIV infection.