title: Identification of a carrier by using Vi enzyme-linked immunosorbent assay serology in an outbreak of typhoid fever on an Indian reservation.
abstract: In May 1981 an outbreak of typhoid fever occurred in a small village on a southwestern United States Indian reservation. Five of the six culture-proven cases, but only 2 of 15 community, age-matched controls, had eaten food prepared for a party held in the village on 20 April (chi-square = 4.3; P less than 0.05). Food histories obtained from 16 persons who ate food at the party suggested that chicken with chili (P = 0.03) and potato salad (P = 0.09) were possible vehicles. Eleven adults who attended the party, 5 of whom helped prepare an implicated food, were studied with one or more stool cultures and serum for Vi antibody by using enzyme-linked immunosorbent assay (ELISA) and hemagglutination techniques. All initial stool cultures were negative for Salmonella typhi; however, one subject, a 70-year-old female foodhandler, had a Vi antibody titer of 1:320 by ELISA. Subsequent cultures from this subject were positive for S. typhi. ELISA for Vi antibody directed the investigators to a single individual as the most probable carrier source and obviated the need for multiple fecal cultures from the other potential carriers identified by the epidemiological investigation.
mesh_terms: D000328:Adult; D000368:Aged; D000942:Antigens, Bacterial / Q000032:analysis*; D001130:Arizona; D002353:Carrier State / Q000175:diagnosis*; D002648:Child; D004196:Disease Outbreaks / Q000453:epidemiology*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005506:Food Contamination; D005511:Food Handling; D006801:Humans; D008297:Male; D011135:Polysaccharides, Bacterial; D012485:Salmonella typhi / Q000276:immunology*; D014435:Typhoid Fever / Q000175:diagnosis / Q000453:epidemiology* / Q000635:transmission
chemical_list: D000942:Antigens, Bacterial; D011135:Polysaccharides, Bacterial