Rapid rises in diagnoses in US gay men concentrated in black and younger men

The number of HIV diagnoses continues to rise in American gay men and other men who have sex with men (MSM), with especially rapid increases seen in young black men, according to figures released by
the Centers for Disease Control and Prevention (CDC) in the June 27^th edition of the Morbidity and Mortality Weekly Report.

The CDC tracked new diagnoses of HIV from 2001-2006, and calculated the estimated annual percentage change in diagnoses. For gay men and other MSM, the annual rise was 1.5%.

The analysis covers the 33 states that had a system of confidential, name-based HIV case reporting throughout the five year period. This includes a number of states with large gay populations, including New York, Florida and Texas, but not others such as California and Illinois.

During this time, a total of 214,379 people were newly diagnosed with HIV, and 46% of the diagnoses were in gay men and other MSM. There were statistically significant decreases in diagnoses for all transmission categories apart from gay men and other MSM. For example, there was a 4.4% annual decrease for heterosexuals, and a 9.5% annual decrease for injecting drug users.

However, diagnoses in gay men and other MSM increased by 1.5% each year (95% CI: 0.8 – 2.1), or 8.6% over the five year period. Moreover, there were marked variations in the increase in diagnoses in gay men and other MSM, according to race and to age.

Annual increases in black men and in Hispanic men were both 1.9%, in contrast to 0.7% seen in white men. A total of 36% of all diagnoses were in black men, although only 12% of the US population is black.

Moreover, the estimated annual increase in Asian and Pacific Island men was 12.1%. However as the total number of infections remains low in this group, the confidence intervals for this figure are relatively wide (95% CI: 5.0 – 19.6).

In terms of age, there were particularly large increases in diagnoses amongst the youngest men in all ethnic groups. For men aged 13-24, looking at all ethnicities together, the increase each year was 12.4%. A particularly large annual increase was seen in young black men – 14.9%, amounting to 93.1% over the five years.

Although the greatest increases were in the youngest men, this group only contributed 14% of the total number of diagnoses. As has long been the case, the majority of diagnoses occurred in the 25-44 age group. However the trends here are more encouraging, with an annual decrease of 1.1%, and decreases concentrated in both white and black men.

Diagnoses increased amongst those aged over 45, however, rising by 2.7% each year. There was a particularly marked increase of 3.8% in white men of this age group (compared to the increase of 0.7% for white men of all ages).

Finally, there were large variations according to region, with greater increases in the South and the Midwest.

During this period, and in contrast to the UK, the US reporting system was not set up to provide accurate measures of HIV incidence (i.e. the rate of new infections in the population). However this data does strongly suggest that incidence is rising in many groups of American men who have sex with men, and may be higher than previously estimated. The number of HIV diagnoses continues to rise in American gay men and other men who have sex with men (MSM), with especially rapid increases seen in young black men, according to figures released by
the Centers for Disease Control and Prevention (CDC) in the June 27^th edition of the Morbidity and Mortality Weekly Report.

The CDC tracked new diagnoses of HIV from 2001-2006, and calculated the estimated annual percentage change in diagnoses. For gay men and other MSM, the annual rise was 1.5%.

The analysis covers the 33 states that had a system of confidential, name-based HIV case reporting throughout the five year period. This includes a number of states with large gay populations, including New York, Florida and Texas, but not others such as California and Illinois.

During this time, a total of 214,379 people were newly diagnosed with HIV, and 46% of the diagnoses were in gay men and other MSM. There were statistically significant decreases in diagnoses for all transmission categories apart from gay men and other MSM. For example, there was a 4.4% annual decrease for heterosexuals, and a 9.5% annual decrease for injecting drug users.

However, diagnoses in gay men and other MSM increased by 1.5% each year (95% CI: 0.8 – 2.1), or 8.6% over the five year period. Moreover, there were marked variations in the increase in diagnoses in gay men and other MSM, according to race and to age.

Annual increases in black men and in Hispanic men were both 1.9%, in contrast to 0.7% seen in white men. A total of 36% of all diagnoses were in black men, although only 12% of the US population is black.

Moreover, the estimated annual increase in Asian and Pacific Island men was 12.1%. However as the total number of infections remains low in this group, the confidence intervals for this figure are relatively wide (95% CI: 5.0 – 19.6).

In terms of age, there were particularly large increases in diagnoses amongst the youngest men in all ethnic groups. For men aged 13-24, looking at all ethnicities together, the increase each year was 12.4%. A particularly large annual increase was seen in young black men – 14.9%, amounting to 93.1% over the five years.

Although the greatest increases were in the youngest men, this group only contributed 14% of the total number of diagnoses. As has long been the case, the majority of diagnoses occurred in the 25-44 age group. However the trends here are more encouraging, with an annual decrease of 1.1%, and decreases concentrated in both white and black men.

Diagnoses increased amongst those aged over 45, however, rising by 2.7% each year. There was a particularly marked increase of 3.8% in white men of this age group (compared to the increase of 0.7% for white men of all ages).

Finally, there were large variations according to region, with greater increases in the South and the Midwest.

During this period, and in contrast to the UK, the US reporting system was not set up to provide accurate measures of HIV incidence (i.e. the rate of new infections in the population). However this data does strongly suggest that incidence is rising in many groups of American men who have sex with men, and may be higher than previously estimated. Rapid rises in diagnoses in US gay men concentrated in black and ...
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