DRUG-RESISTANT PULMONARY TUBERCULOSIS IN THE BAJA-CALIFORNIA SAN-DIEGO COUNTY BORDER POPULATION

A study was conducted to determine the frequency of, and risk factors for, drug-resistant pulmonary tuberculosis (TB) among Baja California (BC) and San Diego County (SDC) residents. Another purpose was to docu ment the amount of contact between pulmonary TB patients and residents of the opposite side of the the border. During the period from Februa ry 1995 to May 1996, pulmonary TB patients from BC (n = 427) and SDC ( n = 331) were evaluated with cultures, drug susceptibility tests, and questionnaires. Drug resistance was found in 41% of the BC Mycobacteri um tuberculosis complex (MTB) isolates and 20% of the SDC isolates. Re sistance to both isoniazid (INH) and rifampin (RIF) varied from 1% of isolates from SDC patients to 17% of isolates from BC patients. Patien ts with a history of previous treatment had increased odds of drug-res istant disease. Older BC patients were more likely to have INH- or RIF -resistant TB. Although 42% of Tijuana TB patients reported recent con tact with residents from SDC, travel to Mexico and contact with reside nts from Mexico were not significant risk factors for drug-resistant T B among SDC residents. However, the demonstrated contact between TB pa tients and residents on opposite sides of the border indicates the imp ortance of coordinating efforts internationally to control TB.