A study by researchers from the University of California, San Diego School of Medicine, in collaboration with Mexican researchers and health officials, shows that as many as 67 percent of injection drug users in Tijuana test positive for tuberculosis (TB) infection. The analysis, which underscores the urgent need for TB screening and treatment for populations that are also at risk for HIV infection, will be published in the May issue of the International Journal of Tuberculosis and Lung Disease (IJTLD).