An article in last week’s MMWR (5) provides instances of the risk of zoonotic infection among people (particularly children) who visit farms for education and recreation (1).
The MMWR article describes two outbreaks of Escherichia coli O157 infection – in different states – in the spring and autumn of 2000, both associated with farm visits (1). In Washington State in May and June 2000 three out of five children aged 2 to 14 years who developed abdominal cramps and diarrhoea required admission to hospital and one developed haemolytic uraemic syndrome (HUS) (5). Four of them had visited a dairy farm where they handled young poultry, rabbits, goats, and a calf, and the fifth was a sibling of a child who had visited the farm and become ill afterwards. Isolates from the children were indistinguishable by pulsed field gel electrophoresis (PFGE), but animal stool specimens yielded no E. coli O157.
The other outbreak, in Pennsylvania, was larger and occurred in the autumn (5). Fifty-one people (age range 1 to 52 years; median 4 years) who had visited a dairy farm developed diarrhoea in the next 10 days: 16 of them were admitted to hospital and eight developed HUS. A case control study (the 51 cases and 92 age-matched controls) showed that illness was associated with contact with cattle, nailbiting, and buying food from outdoor concessions, but that handwashing before eating had a protective effect (5). Isolates of E. coli O157 from patients and 28 cattle were indistinguishable by PFGE.
The MMWR article includes recommendations for action to reduce the risk of transmission of enteric pathogens at petting zoos, open farms, and other places where the public may come in contact with farm animals (5). They focus on the provision of information about the risk, minimisation of risk through design of such facilities, the provision and use of handwashing facilities, avoidance of hand-mouth activities, additional precautions to be taken by those at increased risk of serious infection, and the avoidance of raw milk.
In recent years at around this time of year Eurosurveillance Weekly and other bulletins have reported on the risks of infection associated with recreational and educational visits to farms and of other exposures to livestock (2-4). Escherichia coli O157 infection (2), salmonellosis (3), and cryptosporidiosis (4) have all been described in this context.