EPIDEMIOLOGY OF ISOSPORIASIS AMONG PERSONS WITH ACQUIRED-IMMUNODEFICIENCY-SYNDROME IN LOS-ANGELES-COUNTY

To determine factors associated with isosporiasis in persons with acqu ired immunodeficiency syndrome (AIDS) in Los Angeles County, data from the AIDS surveillance registry were analyzed for the eight-year perio d 1985-1992. Isosporiasis was reported in 127 (1.0%) of 16,351 persons with AIDS during the study period. Prevalence of infection was highes t among foreign-born patients (3.2%), especially those from Fl Salvado r (7.4%) and Mexico (5.4%), and in all persons of Hispanic ethnicity ( 2.9%). Persons with a history of Pneumocystis carinii pneumonia (PCP) were less likely than PCP-negative patients to have isosporiasis (0.2% and 1.4%, respectively, P < 0.01). A decrease in the prevalence of is osporiasis in patients negative for PCP was observed beginning in 1989 (P = 0.02), Prevalence decreased with age (P < 0.01, by chi-square te st for trend). After controlling for multiple factors by logistic regr ession, isosporiasis was more likely to occur in foreign-born patients than in those born in the United States (adjusted odds ratio [OR] = 5 .8, 95% confidence interval [CI] 3.4, 9.9, P < 0.001) and in Hispanics than in whites (non-Hispanics) (adjusted OR = 3.5, 95% CI 1.7, 7.2, P < 0.001), A prior history of PCP continued to be negatively associate d with isosporiasis (adjusted OR = 0.2, 95% CI 0.1, 0.3, P < 0.001). A ge and time remained independently associated with infection. These da ta suggest that isosporiasis among persons with AIDS in Los Angeles Co unty may be related to travel exposure and/or recent immigration and t hat the use of trimethoprim-sulfamethoxazole (TMP-SMX) for PCP may eff ectively prevent primary infection or expression of latent isosporiasi s, Physicians should have an increased index of suspicion for Isospora in AIDS patients with diarrhea who have immigrated from or traveled t o Latin America, among Hispanics born in the United States, in young a dults, and in those not receiving PCP prophylaxis. Food and water prec autions should be advised and TMP-SMX prophylaxis considered for the p revention of Isospora infection for patients with human immunodeficien cy virus infection who travel to Latin America and other developing co untries.