Risk factors for sporadic cases of Escherichia coli O157 infection: the importance of contact with animal excreta

Abstract

To determine environmental risk factors for sporadic E. coli O157 infection in Scotland we undertook a prospective, matched case-control study between 1 October 1996 and 31 March 1999. One hundred and eighty-three cases and 545 matched controls were recruited. Contact with animal faeces (OR = 3.65; 95% CI 1.81, 7.34: P < 0.0005) and likely contact with animal faeces (OR = 4.8; 95% CI 2.42, 9.48; P < 0.0005) emerged as strong risk factors for infection. Certain exposures (mainly food-related) were inversely associated with infection i.e. were statistically protective. Most striking was the consumption of bottled water (OR = 0.28; 95% CI 0.15, 0.52; P < 0.0005). Transmission of E. coli O157 does not occur simply through contaminated food. Members of the public need to be aware of the potential for acquiring E. coli O157 through contamination of the environment with animal faeces so that they may take measures to mitigate their risk.

Laboratory-based surveillance of human verocytotoxigenic Escherichia coli infection in the Republic of Ireland, 2002–2004

“…WHB, and a high level of agriculture had consistently higher levels of VTEC. These findings are consistent with those of Locking et al (2001), who found that contact with animal faeces is a very important risk factor for sporadic E. coli O157 infection. …”

Microbiological quality of organic vegetables produced in soil treated with different types of manure and mineral fertilizer

“…However, much scientific information is produced in the study of detection, survival, fate, and spread of pathogenic microorganisms in animal manure (30,37,44,56,57). This concern is directed to Salmonella spp.…”

“…This contributes to diminishing the environmental pollution from manure disposal (11). However, animal manure is a well-known source of foodborne pathogenic bacteria (32,33,35,37,46,51,61,63,65), and its inappropriate use in vegetable crops, especially organic ones, contributes a risk to consumer health. Research data and regulations recommend evaluating and normalizing the use of animal manure at the agricultural production (20,21).…”

Hemolytic Uremic Syndrome

“…They are found in manure and water troughs in farms, which explains the increased risk for infection in people who live in rural areas. Humans become infected from contaminated milk, meat, and water-water-borne outbreaks have occurred as a result of drinking and swimming in unchlorinated water (21)-or from contact with infected animals, humans, or either's excreta (27,33,34) and occasionally through for rapid detection of E. coli O157:H7 and Stx in stools. Bloody diarrhea, fever, vomiting, elevated leukocyte count, extremes of age, and female gender as well as the use of antimotility agents (37) have been associated with an increased risk of HUS after E. coli infection (27).…”