Zoogoers need to be careful when coming into contact with animals at petting zoos because of the risk of contracting highly infectious diseases.
In a study presented at the European Congress of Clinical Microbiology & Infectious Diseases, researchers from Ariel University in Israel discussed the growing threat of multidrug-resistant (MDR) bacteria found in many animal containment facilities such as zoos.
With petting zoos becoming more popular among children and adults alike, health experts fear that exposure to MDRs might get out of hand and lead to more cases of highly virulent drug-resistant pathogens.
Multidrug-Resistant Bacteria In Petting Zoos
Petting zoos present health officials with a different dynamic in terms of preventing infectious diseases. Unlike regular zoos, visitors can often approach animals in petting zoos and interact with them directly. Children can even pet and hold different animals such as rabbits, monkeys, and horses.
However, this direct contact also exposes zoogoers to different microorganisms found in many animals.
Researchers are particularly concerned about AmpC-producing Enterobacteriaceae (AmpC-E) and other bacteria that carry extended spectrum beta-lactamase (ESBL) enzymes. Such microbes can infect both humans and animals and have been found to be highly resistant to antibiotics.
AmpC And ESBL
Shiri Navon-Venezia, a professor at Ariel University, led a team in examining eight petting zoos found all over Israel. She and her colleagues analyzed samples taken from 228 different animals.
The researchers made use of genetic sequencing to pinpoint the different bacterial species found in each sample. They also looked for possible drug-resistance genes from AmpC and ESBL in the animals.
Zoo owners were also surveyed regarding the ages and medical histories of the animals under their care.
The data was used to examine additional risk factors found in the animals.
Navon-Venezia and her team found that as much as 12 percent of animals tested were infected with at least a single bacterial strain related to AmpC or ESBL. They also recovered 35 different bacterial species.
A majority (77 percent) of the MDR microbes were found in the animals feces, while the remaining 23 percent were taken from their feathers, fur, and skin.
A quarter of the animals that had MDR bacteria tested positive for more than one bacterial strain. Among the microbes found in the subjects were E. coli ST127, which is known to trigger urinary tract infections; and E. coli ST656, which is related to travelers' diarrhea.
The findings also showed that if infected animals were exposed to antibiotics, they were seven times more likely to produce multidrug-resistant bacteria.
The high number of different animals found in petting zoos makes these areas a primary source for AmpC-E and ESBL species. These microbes are likely to shed many highly virulent pathogens, which can infect zoogoers. Children are the most at risk to disease transmission since they are the ones that often come in direct contact with the animals.
"We recognise the high educational and emotional value of petting zoos for children," Navon-Venezia noted.
"[T]herefore, we strongly recommend that petting zoo management teams implement a strict hygiene and infection control policy, together with rationalised antibiotic policy, in order to reduce the risk of transmission between animals and visitors."