from www.latimes.com – A large percentage of men who regularly have sex with prostitutes in Tijuana do not use condoms and have a history of drug and alcohol abuse, according to a binational study published Friday in the online journal AIDS.

Of 400 men who answered questions for researchers from Mexico and UC San Diego, about half were from Mexico and the rest from the U.S., which suggests that their risky behavior could spread AIDS and other diseases on both sides of the border.

The researchers said that Tijuana has a “thriving” prostitution trade and though local authorities regularly test registered “sex workers” for AIDS, only about half of prostitutes have registered or been tested.

More than half of the men had had unprotected sex within the last four months, the researchers found. The average customer is 36 years old, unmarried and visits prostitutes more than 25 times a year.

Many reported being under the influence of drugs, particularly methamphetamine, while having sex with a prostitute.

Thomas L. Patterson of the UC San Diego’s department of psychiatry and the Veterans Affairs health center, said the study’s results show the need for an education campaign aimed at men who frequent prostitutes about the dangers involved.