Not surprisingly public health investigators from the North Carolina Department of Health and Human Services have determined that the petting zoo at the Cleveland County Fair was the initial source of exposure to E. coli that resulted in 106 illnesses and one death. According to results presented today in Shelby, weather may be one of the factors that played a role in widespread contamination of the area surrounding the petting zoo exhibit.

The Cleveland County investigation, which began October 8, involved a case control study of those who became ill as well as an additional 160 individuals who attended the fair but did not become ill. Local health department personnel in Cleveland, Gaston, Lincoln, Catawba, Rutherford and Union counties conducted 266 extensive interviews in the weeks following the outbreak.

In addition to the case control study, analysis by the State Laboratory of Public Health and United States Department of Agriculture confirmed two specific strains of E. coli in cases from the outbreak that were matched to environmental samples taken from the fairgrounds. Investigators noted that heavy rains during the run of the fair, from September 29 through October 8, resulted in runoff that may have spread contamination from the petting zoo into nearby areas.

After decades of outbreaks, the CDC and a collection of state veterinarians have issued these stern warnings and suggestions about animal exhibits and petting zoos:

– Wash hands after contact with animals to reduce the risk of zoonotic disease transmission.

– Do not allow food, drink, or pacifiers in animal areas.

– Include transition areas between animal areas and non-animal areas.

– Educate visitors about disease risk and prevention procedures.

– Properly care for and manage animals.

But, if history is any guide, guidelines are not working very well.  Here is a sample of zoonotic outbreaks over the last decade:

2011 English Animal Farm Outbreak – Cruckley Animal Farm in Foston-on-the-Wolds, England is closing its gates permanently following an outbreak of E. coli O157:H7.  The family-run farm was linked to at least six cases of the life-threatening infection as of August 2011.  The owners, John and Sue Johnston, expressed sorrow at the illness and stated that “the health and safety of our visitors has always been our top priority,” thus with the news the farm was the likely source of illnesses, they decided to close.

2011 Snohomish County Petting Zoo – At least 6 people who visited the Forest Park Petting Zoo in Everett, Washington, in June 2011 became ill with E. coli O157:H7 infections. The Snohomish County Health Department investigated the E. coli outbreak and determined that there was a “clear association between disease and being in the open animal interaction area of the forest Park Animal Farm.”

2009 Utah Rodeos Outbreak – Utah state and local health officials and the CDC noted a cluster of E. coli O157:H7 cases in the summer of 2009.  The illnesses were associated with attendance to rodeos, but not all the same one.  The vast majority of the 14 cases (93 percent) had food histories containing ground beef, unsurprising for rodeo visitors.  However, a traceback on the meat products provided at the rodeos found no contamination.

2009 Godstone Park Farm and Plan Barn E. coli Outbreak in Surrey, England – A final report of the Outbreak Control Committee of the Surrey and Sussex Health Protection Unit describes an outbreak of E. coli O157 (VTEC O157 PT21/28) occurring in August and September 2009. This was the largest documented outbreak of VTEC O157 associated with farms in the UK. Individuals became infected either through direct or indirect contact with farm livestock.

2009 “Feed the Animals” Exhibit E. coli Outbreak at the Western Stock Show – In January 2009, the Communicable Disease and Consumer Protection Divisions of the Colorado Department of Public Health noticed an increase is in the number of laboratory confirmed cases of E. coli O157.  Thirty cases were identified–including nine hospitalizations and 2 cases of HUS.  All the children had visited the National Western Stock Show in Denver, Colorado.

2007 Petting Zoo E. coli O157:H7 Outbreak in Pinellas County, FL – In May and June 2007, seven Florida children were infected with E. coli O157:H7. Six of the children had visited a Day Camp petting zoo, and the seventh was a sibling. Two of the children were hospitalized, all seven recovered.  The petting zoo was closed on the recommendation of the health department.

2005 Big Fresno Fair Petting Zoo E. coli Outbreak – At least six children were infected with E. coli O157:H7 – one gravely – visiting the petting zoo at the 2005 Big Fresno Fair. One child was 2 years old at the time of her visit to the petting zoo. She developed HUS and was hospitalized for months. Her kidneys were severely damaged and a series of strokes left her with impaired movement and vision.

2005 Campylobacteriosis Outbreak Associated with a Camping Trip to a Farm – In June 2005, King County Public Health was notified that a several children on a school trip had been ill with diarrhea, abdominal pain and fever following the trip. Campylobacter was isolated from the stool of one ill individual, and later in the week, two more cases of campylobacteriosis were reported in persons who had been on the same camping trip, held at a private farm.

2005 Florida State Fair, Central Florida Fair, and Florida Strawberry Festival E. coli Outbreak – The AgVenture Farms E. coli O157:H7 outbreak was first recognized after two separate HUS case reports were reported to the Florida Department of Health in mid-March.  The two cases (a 5-year-old girl and a 7-year-old boy) both reported having visited a fair with a petting zoo (AgVenture) a few days prior to becoming ill. The two children did not have any other common risk factors. A total of 22 confirmed, 45 suspect and 6 secondary cases were reported.

2003 Fort Bend County Fair E. coli Outbreak – Rosenberg, TX – In 2003, 25 people (fair visitors and animal exhibitors) became ill with HUS and one case of a related disease, thrombotic thrombocytopenic purpura. All seven laboratory-confirmed cases had an indistinguishable PFGE pattern, which matched 10 isolates obtained from environmental samples taken from animal housing areas.

2002 E. coli Outbreak at a Petting Zoo in Zutphen, The Netherlands  – A young child developed a Shiga toxin 2 producing strain of Escherichia coli (STEC) O157 infection after visiting a petting zoo in Zutphen, The Netherlands. The STEC strains were isolated from the fecal samples from goats and sheep on the farm and were indistinguishable from the human patient isolate.

2002 Lane County, Oregon, Fair E. coli Outbreak – The Oregon Department of Human Services (Oregon, 2002) initially documented a patient with bloody diarrhea, who attended the Lane County Fair held during August 2002. Epidemiologists identified 82 ill persons, 22 who were hospitalized, and 12 with HUS. This is the largest E. coli O157:H7 outbreak recorded in Oregon.

2002 Wyandot County, OH, Fair E. coli Outbreak – The Ohio Wyandot County Health Department received a report of an E. coli O157 outbreak in September 2001 (CDC memorandum, February, 2002). A total of 92 cases were identified, including 27 laboratory-confirmed E. coli O157 infections. Two cases were diagnosed with hemolytic uremic syndrome. Eighty-eight cases reported attending Wyandot County Fair before becoming ill.

2001 Lorain County, OH, Fair E. coli Outbreak – The Department of Health and Human Services, Public Health Services (CDC memorandum, February, 2002) reported that 23 cases of E. coli O157:H7 infection were associated with the attendance at the Lorain County Fairgrounds in September 2001. Additional cases were identified as likely due to secondary transmission from attendees at the fairgrounds. An investigation associated illness with environmental contamination at the Cow Palace.

2001 Ozaukee County, WI, Fair E. coli Outbreak – The Ozaukee County Public Health Department and Wisconsin Department of Health and Family Services (2001) investigated an outbreak of E. coli O157:H7 associated with animals at the Ozaukee County Fair in August 2001. A total of 59 E. coli O157:H7 cases were identified in this outbreak, with 25 laboratory confirmed cases (25 “primary cases” and 34 probable cases).

2001 E. coli Outbreak at a Petting Zoo in Worcester, PA – An article published by WebMD Medical News on April 23, 2001 (Bloomquist, 2001), reported an outbreak of E. coli O157:H7 among visitors to the Merrymead Farm petting zoo in Worcester, Pennsylvania. In all, 16 children who had visited the zoo contracted E. coli, and it was suspected that another 45 people became ill from the bacteria. The report indicated that one week after visiting the zoo, one of the children came down with violent stomach cramps and was hospitalized.