CDC releases strategies to prevent diseases transmitted to humans from farm animals

CDC released today new strategies designed to reduce the risk of disease transmission from animals to people at venues where people have contact with farm animals.

Last year outbreaks of Escherichia coli O157:H7 in Washington and Pennsylvania associated with visits to farms sickened 56 people and led to 19 hospitalizations. These outbreaks as well as data from other studies demonstrated the need to develop these strategies which are published in the April 20 issue of Morbidity and Mortality Weekly Report

"Each year many young children across the country come in contact with farm animals at petting zoos, petting farms, and county fairs where they may be putting themselves at risk of getting a life threatening infection like E. coli O157:H7," said CDC Director Dr. Jeffrey Koplan. "Managers of these venues as well as parents of children who visit them should be aware of these risks and should assure that the strategies to minimize them are in place.

The strategies summarized below include:

1. Information should be provided. Persons providing public access to farm animals should inform visitors about the risk of transmission of enteric pathogens from farm animals to humans and strategies for prevention of such transmission.

2. Venues should be designed to minimize risk. Farm animal contact is not appropriate at food service establishments and infant care settings, and special care should be taken in settings with school-aged children. At venues where farm animal contact is desired, layout should provide a separate area for humans where the animals are not allowed, as well as an 'interaction' area. Animal petting should occur only in the interaction area to facilitate close supervision and coaching of visitors.

3. Hand-washing facilities should be adequate. Hand-washing stations should be available to both the animal-free area and the 'interaction' area. Running water, soap, and disposable towels should be available so that participants can wash their hands immediately after contact with the animals. Children under 5 years old should wash their hands with adult supervision.

4. Hand to mouth activities should not be permitted in 'interaction' areas. Hand to mouth activities such as eating and drinking, smoking, and carrying toys and pacifiers should not be permitted in 'interaction' areas.

5. Persons at high risk for serious infections should observe heightened precautions. Farm animals should be handled by everyone as if the animals are colonized with human enteric pathogens. However, children under 5 years, the elderly, pregnant women, and immunocompromised persons (e.g., those with HIV/AIDS) are at higher risk of serious infections. Such persons should weigh the risks of contact with farm animals. If allowed to have contact, children under 5 years should be closely supervised by adults, with precautions strictly enforced.

6. Raw milk should not be served. Most people become infected with O157 primarily by ingesting food (including meat, produce, fruit, and juice) or water contaminated by animal feces, according to Dr. John Crump, CDC epidemiologist who investigated the outbreak in Pennsylvania. "In addition, people can become infected by petting farm animals or touching their surroundings which are contaminated with animal feces, and then putting their unwashed hands in or around their mouth," he said.

CDC developed these strategies in collaboration with the United States Department of Agriculture and the National Association of State Public Health Veterinarians. The agency is seeking suggestions or comments concerning the strategies until July 2001.

CDC protects people's health and safety by preventing and controlling diseases and injuries; enhances health decisions by providing credible information on critical health issues; and promotes healthy living through strong partnerships with local, national and international organizations.