Most positive HIV western blot tests do not diagnose new cases in New York City: implications for HIV testing programs.
OBJECTIVE
To evaluate HIV testing efforts based on surveillance data.


METHODS
We determined the contribution of new diagnoses to all positive confidential HIV-1 Western blotting conducted in New York City between 2004 and 2006 based on clinical history recorded in the HIV Surveillance Registry, by testing site type.


RESULTS
Of 31,504 positive Western blots reported and linked to Registry cases, 36.8% were new diagnoses and 63.2% were repeat positive tests. City health department clinics and private physicians' offices reported greater proportions of new diagnoses than other testing sites (64.4% and 58.3% vs. 31.1%). The percentage of positive tests at health department clinics that were new diagnoses increased from 59.8% in 2004 to 69.0% in 2006 (P = 0.001), coinciding with efforts to expand HIV testing. Repeat positive testers were significantly older, more likely to have an injection drug use history or AIDS, and less likely to be foreign-born.


CONCLUSIONS
Repeat testing of known HIV-infected persons is common and an inefficient use of HIV prevention resources when the purpose of testing is to diagnose previously unidentified infections. Initiatives to increase HIV testing should be evaluated routinely using surveillance data to determine the proportion of infected persons identified who are newly diagnosed.
HIV Epidemiology and Field Services Program, Bureau of HIV/AIDS Prevention and Control, New York City Department of Health and Mental Hygiene, New York, NY, USA. dhanna@jhsph.edu
David B
DB
Hanna
Benjamin W
BW
Tsoi
Elizabeth M
EM
Begier
D000328:Adult; D015153:Blotting, Western / Q000706:statistics & numerical data; D005260:Female; D015658:HIV Infections / Q000175:diagnosis* / Q000453:epidemiology / Q000517:prevention & control; D015497:HIV-1; D006300:Health Services Misuse; D006801:Humans; D008297:Male; D009519:New York City / Q000453:epidemiology; D011159:Population Surveillance; D012042:Registries