title: Age-specific frequencies of antibodies to Escherichia coli verocytotoxins (Shiga toxins) 1 and 2 among urban and rural populations in southern Ontario.
abstract: In 173 urban residents and 232 rural dairy-farm residents (age range, 0-70 years) who were stratified for age, the frequency of antiverocytotoxin 2 antibodies (VT2 Abs) (frequency in urban residents, 46%; frequency in rural residents, 65%) was significantly higher than that of antiverocytotoxin 1 antibodies (VT1 Abs) (frequency in urban residents, 12%; frequency in rural residents, 39%) (P< or =.001). The frequency of VT2 Abs (93%) was also significantly higher than that of VT1 Abs (50%) in 14 patients with hemolytic uremic syndrome (HUS) associated with verocytotoxin-producing Escherichia coli (VTEC) strains that expressed both toxins. In urban residents, the frequency of both antibodies tended to decrease between the first and the second decades of life, and it then increased until the fifth decade of life, before, in the case of VT2 Abs, decreasing again. This pattern, which inversely reflects the age-related incidence of HUS, is consistent with a role for antiverocytotoxin antibodies in protective immunity. In dairy-farm residents, peak frequencies of antibodies to both toxins occurred during the first decade of life and remained elevated for 3 decades before decreasing, a pattern consistent with frequent exposure to bovine VTEC from an early age.
authors.affiliation: Laboratory for Foodborne Zoonoses, Population and Public Health Branch, Health Canada, Guelph, Ontario, Canada. Mohamed_Karmali@hc-sc.gc.ca.
authors.forename: Mohamed A
authors.initials: MA
authors.lastname: Karmali
authors.forename: Mariola
authors.initials: M
authors.lastname: Mascarenhas
authors.forename: Martin
authors.initials: M
authors.lastname: Petric
authors.forename: Lucie
authors.initials: L
authors.lastname: Dutil
authors.forename: Kris
authors.initials: K
authors.lastname: Rahn
authors.forename: Kerstin
authors.initials: K
authors.lastname: Ludwig
authors.forename: Gerald S
authors.initials: GS
authors.lastname: Arbus
authors.forename: Pascal
authors.initials: P
authors.lastname: Michel
authors.forename: Philip M
authors.initials: PM
authors.lastname: Sherman
authors.forename: Jeff
authors.initials: J
authors.lastname: Wilson
authors.forename: Roger
authors.initials: R
authors.lastname: Johnson
authors.forename: James B
authors.initials: JB
authors.lastname: Kaper
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000907:Antibodies, Bacterial / Q000097:blood*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006463:Hemolytic-Uremic Syndrome / Q000382:microbiology; D006801:Humans; D015151:Immunoblotting; D007223:Infant; D008297:Male; D008875:Middle Aged; D012423:Rural Health; D022622:Shiga Toxin 1 / Q000276:immunology*; D022641:Shiga Toxin 2 / Q000276:immunology*; D014504:Urban Health
chemical_list: D000907:Antibodies, Bacterial; D022622:Shiga Toxin 1; D022641:Shiga Toxin 2