title: Association of virulence factor-positive and -negative enteroaggregative Escherichia coli and occurrence of clinical illness in travelers from the United States to Mexico.
abstract: The objective of the study was to determine if the presence or absence of virulence factor-positive and -negative enteroaggregative Escherichia coli (EAEC) determined the occurrence of illness or sub-clinical EAEC infection in travelers from the United States to Mexico. Sixty-five newly arrived college students from the United States submitted weekly stool samples for a four-week period of time. Among EAEC-infected subjects, diarrhea occurred in those with a defined virulence factor with the following frequency: aggA, 5 of 15 (33%); aggR, 3 of 11 (27%); aafA, 3 of 8 (38%); and aspU, 1 of 6 (17%). Twenty-two of 31 students (71%) had two or more EAEC infections. After the initial EAEC infection, only 4 (11%) of 31 students had a subsequent symptomatic EAEC infection. Our study suggests that clinical illness by EAEC is not explained by presence of a defined EAEC virulence factors, and we provide suggestive evidence that EAEC infection protects against future symptomatic infection.
authors.affiliation: Department of Medicine, Baylor College of Medicine, Houston, Texas 77030, USA. dhuang1@bcm.tmc.edu
authors.forename: David B
authors.initials: DB
authors.lastname: Huang
authors.forename: Zhi-Dong
authors.initials: ZD
authors.lastname: Jiang
authors.forename: Herbert L
authors.initials: HL
authors.lastname: Dupont
mesh_terms: D000293:Adolescent; D000328:Adult; D003967:Diarrhea / Q000453:epidemiology* / Q000209:etiology / Q000382:microbiology; D004926:Escherichia coli / Q000472:pathogenicity*; D004927:Escherichia coli Infections / Q000453:epidemiology* / Q000209:etiology / Q000382:microbiology; D005243:Feces / Q000382:microbiology; D005260:Female; D006801:Humans; D008297:Male; D008800:Mexico / Q000453:epidemiology; D011446:Prospective Studies; D014195:Travel; D014481:United States; D037521:Virulence Factors / Q000235:genetics
chemical_list: D037521:Virulence Factors