Research Team: Oliver L. Haimson, Jed R. Brubaker, Gillian R. Hayes

How have personal ads changed in the last 30 years, and how has the HIV/AIDS crisis influenced these changes?

We analyzed 250,000 personal ads for men who have sex with men from the online classifieds website Craigslist.org and found that:

• The percentage of ads using sexual health-related language have increased from 23% in 1988 to 53% today.
• Use of sexual health-related language in a location correlates with HIV prevalence rates (r = 0.27).

Results highlight the potential for online personal ads to serve as a sensor for public health surveillance purposes, which may help to combat the spread of HIV.