title: Burden and transmission of zoonotic foodborne disease in a rural community in Mexico.
abstract: BACKGROUND
  The foodborne transmission and human health impact of Salmonella and Campylobacter infections have rarely been evaluated at the population level in highly endemic settings.
  
  
  METHODS
  A prospective 15-month cohort study of 127 infants and 119 elderly people was combined with animal and food surveillance to determine the incidence and severity of Salmonella and Campylobacter gastroenteritis in a comparatively prosperous rural community in Mexico.
  
  
  RESULTS
  Salmonella and Campylobacter were isolated in up to 75% and 57%, respectively, of raw retail meat and in up to 4.5% of ready-to-eat foods. Rates of acute gastroenteritis of any etiology in infants and elderly people were, respectively, 2.1 and 0.7 episodes per person per year. The annual incidence density rate of Salmonella gastroenteritis was 17.8 per 100 infants and 7.9 per 100 elderly people; the rate of Campylobacter gastroenteritis was 11.7 per 100 infants and 0 per 100 elderly people. Pulsed-field gel electrophoresis analysis yielded multiple clusters of human, meat, and/or animal Salmonella and Campylobacter isolates with indistinguishable patterns. On average, gastroenteritis episodes with these pathogens lasted 3 days in infants and 2 days in elderly people. Medical attention was sought in 44% of diarrheal episodes in infants and in 26% of diarrheal episodes in elderly people; none required hospitalization. Infants with multidrug-resistant Salmonella gastroenteritis had a higher frequency of bloody stools and medical visits (50% vs 11%; odds ratio, 8.5; P = .04) than those with more susceptible strains.
  
  
  CONCLUSIONS
  In this relatively advantaged Mexican rural community, the human health impact of a food chain heavily contaminated with Salmonella and Campylobacter was of low magnitude.
authors.affiliation: Microbiology Research Laboratory, Hospital General O'Horan, Mérida, Yucatán, Mexico. mbzaidi@prodigy.net.mx
authors.forename: Mussaret B
authors.initials: MB
authors.lastname: Zaidi
authors.forename: Freddy D
authors.initials: FD
authors.lastname: Campos
authors.forename: Teresa
authors.initials: T
authors.lastname: Estrada-García
authors.forename: Flor
authors.initials: F
authors.lastname: Gutierrez
authors.forename: Magda
authors.initials: M
authors.lastname: León
authors.forename: Rodolfo
authors.initials: R
authors.lastname: Chim
authors.forename: Juan J
authors.initials: JJ
authors.lastname: Calva
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002169:Campylobacter Infections / Q000453:epidemiology* / Q000382:microbiology; D016123:Campylobacter jejuni / Q000145:classification / Q000235:genetics / Q000302:isolation & purification; D002417:Cattle; D016009:Chi-Square Distribution; D016000:Cluster Analysis; D018562:Disease Transmission, Infectious / Q000706:statistics & numerical data*; D016521:Electrophoresis, Gel, Pulsed-Field; D019353:Endemic Diseases; D005260:Female; D020387:Food Chain; D005759:Gastroenteritis / Q000453:epidemiology / Q000382:microbiology; D006801:Humans; D007223:Infant; D008297:Male; D008460:Meat / Q000382:microbiology; D008800:Mexico / Q000453:epidemiology; D008826:Microbial Sensitivity Tests; D015995:Prevalence; D011446:Prospective Studies; D012424:Rural Population / Q000706:statistics & numerical data*; D012478:Salmonella Food Poisoning / Q000453:epidemiology* / Q000382:microbiology; D012481:Salmonella Infections, Animal / Q000453:epidemiology / Q000382:microbiology; D012486:Salmonella typhimurium / Q000145:classification / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification; D012959:Socioeconomic Factors; D013552:Swine; D015047:Zoonoses
chemical_list: D000900:Anti-Bacterial Agents