Less than half of New Yorkers who become HIV positive are diagnosed within a year of seroconversion, and rates are even lower among people of color, according to a study conducted by epidemiologists with the New York City Department of Health and Mental Hygiene and the Centers for Disease Control and Prevention. The study, published in AIDS, suggests this metric can be a useful outcome indicator to help guide public health authorities’ testing efforts.
Early diagnosis of HIV, of course, allows for early initiation of treatment, which in turn not only preserves immune function, but also reduces viral load and lowers the risk of onward transmission.
The current study utilized New York City data between 2012 and 2016, using a person’s first CD4 cell count after diagnosis and a CD4 depletion model to estimate time since seroconversion. During the study period, the annual probability of an HIV diagnosis within one year of acquiring the virus remained fairly stable in the city, around 42% to 43%.
However, disparities emerged, with non-white people less likely to be diagnosed early than whites, and people under the age of 25 less likely to be diagnosed than those who are 25 or older. Reduced likelihood of early diagnosis was also seen among people who use injection drugs and people whose HIV transmission risk activity was heterosexual sex.
Large data sets are needed for the diagnosed-within-one-year probability metric to be reliable, which may make it unsuitable for some areas, study authors acknowledged. Nonetheless, they recommended its widespread use, concluding, “[w]e recommend that the nation and local health jurisdictions use this new indicator ... to monitor their progress towards ending the HIV epidemic in the United States.”