The changing epidemiology of human brucellosis in Texas, 1977-1986.

From 1977-1986, a total of 331 laboratory confirmed cases of human brucellosis were reported in Texas. The annual number of cases ranged from 13 in 1977 to 84 in 1983. Males accounted for 66% of the cases. Cases ranged in age from one to 92 years, with 57% between the ages of 20 and 49 years. Brucella melitensis infections accounted for 66% of the bacteriologically confirmed cases. Infection with Brucella canis was identified in four patients. Annual incidence rates were higher in Hispanics in each age and sex group when compared with whites and blacks. Epidemiologic features of cases reported during 1977-1981 are dissimilar to features of cases reported during 1982-1986. In the first five years, a majority of cases (82%) were males, and a majority (54%) were white. Exposure to cattle or swine was reported for 72% of the cases. In the second five years, a majority (72%) of cases were Hispanic, and only 55% were males. Ingestion of unpasteurized goat milk products was reported for 67% of the cases during 1982-1986.