December 17, 2009
Health Dangers at Petting Zoos and Fairs
E. coli infections are a serious risk, especially for children
In December 2002, Pennsylvania passed a bill requiring petting zoos and other animal exhibits to provide hand-washing facilities and to post information about the more than 75 diseases humans can contract from contact with animals. The impetus for the bill was a an outbreak of E. coli in 2000 among visitors, most of them children, to a Montgomery County petting zoo. The Centers for Disease Control and Prevention (CDC) reported that 55 cases of E. coli were confirmed, and 16 people were hospitalized. One child, a four-year-old girl, required a kidney transplant from her father.
According to the CDC, each year an estimated 73,000 people become ill and 60 people die from the potentially life-threatening bacteria, E. coli O157:H7. Although many cases are due to contaminated food and water, transmission of E. coli from animals to people is a growing concern. In 2007, the CDC identified seven cases associated with a petting zoo at a Florida day camp. This outbreak occurred despite the use of prevention measures that generally adhered to recommendations of the National Association of State Public Health Veterinarians. There were four handwashing facilities with liquid soap, running water operated by a foot pedal, and disposable towels, signs said no food or drink was allowed in the animal area and that visitors should wash their hands upon exiting, and a staff member was required to be present near the zoo exit.
What is E. coli?
There are hundreds of E. coli (Escherichia coli) strains. Most of these bacteria are harmless and occur naturally in the intestines of healthy people and animals. Others, such as E. coli O157:H7, are potentially deadly forms of bacteria that may cause severe illness, permanent kidney damage, brain damage, and even death in humans.
How Is E. coli transmitted to people?
E. coli O157:H7 is carried by many animals, including farm animals such as cows and goats. The animals do not appear ill from the bacteria. There is no way to tell if an animal is carrying E. coli O157:H7 bacteria other than by performing a laboratory test. People who come into contact with the feces of an infected animal and who do not take proper hygienic measures such as hand washing can become infected with the bacteria. Contact can occur from touching animals or any surface that may be contaminated with the feces of the animal, which in outdoor areas could be nearly any surface. Pregnant women, elderly persons, and immuno-compromised individuals should avoid contact with animals due to their heightened risk of complications from infection.
Children are at the greatest risk for serious complications caused by E. coli infection. This problem is compounded by the fact that children are difficult to control during zoo and fair visits, and are the least likely to understand or follow hygiene rules around animals. Young children display constant hand-to-mouth activity. Consequently, some zoos and fairs discourage or prohibit children under five years of age from having any contact with the animals.
What are the symptoms?
E. coli infection in humans causes severe abdominal cramps and bloody diarrhea, which may appear several days after infection. A fever may or may not be present. In the least severe cases, symptoms may last five to ten days. Life threatening complications, including kidney failure, are possible—especially in young children and infirm adults. If symptoms occur in young children or persons with compromised immune systems, they should be tested for E. coli infection immediately.
How can E. coli infection be prevented?
The best way to prevent infection is to avoid any direct contact with farm animals and their enclosures. If you do have contact with these animals, hygienic measures should be taken to help prevent infection from E. coli bacteria. Animal exhibits that allow human-animal contact should provide visitors with information on the possibility of infections from the animals. Such operations should also provide patrons with hand-washing facilities that contain running water, soap, and disposable towels. Neither food nor eating should be permitted near the animals or their enclosures.
Other health dangers at animal attractions
Animal attractions that allow human-animal contact present many opportunities for zoonotic diseases to spread. In August 1999, a young black bear exhibited at a Iowa petting zoo died of rabies. Because the petting zoo permitted individuals to pet and wrestle with the bear, and the bear had been seen licking and nipping humans, the CDC suggested that people who had recent contact with the bear contact their doctors to see if rabies vaccinations were necessary. Wild animals also pose a risk of attacking and injuring zoo visitors and are not appropriate for use in petting zoos.
Direct contact with animals is not necessary to contract most zoonotic diseases; indirect contact with contaminated surfaces is sufficient.