New HIV cases decline in US, but population and geographic disparities persist

HIV diagnoses have declined by nearly 20% overall during the past decade but progress has been uneven across demographic groups, according to new Centers for Disease Control and Prevention (CDC) data reported at the 2015 National HIV Prevention Conference taking place this week in Atlanta.

One encouraging finding was a levelling off of newly diagnosed infections among black gay and bisexual men in recent years, following a steady rise. However, the CDC also reported disappointing new data on geographical disparities, showing that death rates among people with HIV are three times higher in southern US states.

"It is the best of times and the worst of times [in HIV], with some success and some major disparities," said Jonathan Mermin, director of CDC’s National Center for HIV/AIDS, Viral Hepatitis, STD and TB Prevention, who opened the conference on Sunday and gave a Monday plenary address on the CDC's high-impact HIV prevention initiative, which aims to focus resources on the most effective interventions and the most heavily affected groups.

"All interventions are not effective, and all effective interventions are not equal," Dr Mermin said. "Limited resources demand choices. Targeted PrEP [pre-exposure prophylaxis] and syringe distribution are cost-effective and cost-saving...The biggest impact will come from getting [people living with HIV] diagnosed and into care."

Diagnosis trends by demographic group

The CDC released data at the conference from a national analysis of trends in HIV diagnoses over two time periods – 2005 to 2014 and 2010 to 2014 – to provide both a decade-long perspective and a look at more recent changes.

Findings showed that annual HIV diagnoses in the US fell by 19% overall between 2005 and 2014 (from 48,795 to 39,718 per year), which the agency attributed to "dramatic and continuing declines over the decade among several populations including heterosexuals, people who inject drugs, and African Americans."

Newly diagnosed infections fell by 35% among heterosexuals, by 40% among all women (from 12,499 to 7533), by 42% among black women and by 63% among people who inject drugs between 2005 and 2014. During the more recent period, black women saw the steepest drop, of 25%.

The same level of success was not uniformly seen among men who have sex with men – a group that accounts for nearly two-thirds of all new HIV diagnoses in the US. Overall, new diagnoses among gay and bisexual men rose by 6% over the decade (from 25,155 to 26,612), before stabilising in recent years at a less than 1% increase. This rise among gay men combined with a decline among heterosexual men led to a modest 11% decrease for all men (from 36,296 to 32,185).

However, for gay men trends differed substantially according to race/ethnicity. White gay and bisexual men saw an 18% decline in newly detected infections over the decade (from 9966 to 8207) – similar to that of the population as a whole. In contrast, new diagnoses among black and Latino gay and bi men rose by 22% (from 8235 to 10,080) and by 24% (from 5492 to 6829), respectively.

But there has been an encouraging levelling off in new diagnoses among black men during the last five years, with a less than 1% increase. Looking specifically at young black gay and bi men aged 13 to 24 years, this group experienced a steep 87% increase in newly diagnosed infections over the entire decade (from 2094 to 3923), but a 2% decline between 2010 and 2014. Unfortunately the same trend was not apparent for young Latino men, who saw diagnoses rise by 16% in recent years.

HIV testing remained stable or increased during the study period, according to the CDC, indicating that the decreases or stabilisations cannot be attributed to fewer people being tested.

"[This data] tells us that our prevention strategies are working, but progress is uneven across populations," said Eugene McCray, director of CDC's Division of HIV/AIDS Prevention, who presented the data at a plenary address on Sunday. "We urgently need to accelerate access to testing, treatment and new biomedical prevention strategies so that everyone can protect themselves and their partners."

Dr McCray suggested that it is unlikely that the declines and stabilisations are due to any specific single intervention – such as pre-exposure prophylaxis (PrEP), which is only now coming into widespread use – but is more likely attributable to a combination of prevention efforts including getting more people living with HIV into care and on treatment, which both improves their own health and reduces transmission to others.

Geographical disparities

Dr McCray also presented new data on differences across states in death rates among people living with HIV and in the number of people who know their HIV status.

Data from 2012 show that the national mortality rate among people with HIV was 19.2 deaths per 1,000 people. But this varied by state, from a low of 7.9 deaths per 1,000 in Vermont to a high of 30.8 per 1,000 in Louisiana. Of the ten states that failed to meet the national goal for reducing HIV deaths, seven were in the southeast US.

Looking at rates of HIV diagnosis, 87% of people in the US knew their HIV status in 2012, but again there was a wide range, from a low of 77% in Louisiana to a high of 93% in New York State and Hawaii. Just five states reached the national goal of 90%, and again the worst performing states were in the south.

"It is unacceptable that people with HIV living in many southern states are more likely to die than those living in other parts of the country," Mermin said in a CDC press release. "Some states are making great strides toward getting people with HIV diagnosed and into care, but every state must do this if we are to reach our national goals for prevention and care."

"We need to ensure everyone living with HIV has access to high quality health care no matter where they live," Dr McCray stressed.