Petting zoos a breeding ground for drug-resistant superbugs, study finds

‘Petting zoos can result in shedding and transmission of multi-drug resistant pathogens that may cause illness for human visitors, even when the animals appear healthy’

E coli and other drug-resistant bacteria can cause illness when ingested and can easily spread to others (Getty/iStock)

Petting zoos could be a breeding ground for drug-resistant superbugs after a study found more than one in 10 animals carrying at least one strain of bacteria capable of withstanding multiple important antibiotics.

Israeli researchers collected samples from 228 animals across eight randomly chosen petting zoos, and concluded they were “reservoirs” for microbes that could easily spread from children to vulnerable relatives.

Antibiotic resistance has been dubbed a global health emergency which the UK’s chief medical officer has said could push medicine back to the “dark ages” – when even minor cuts or surgery raised the prospect of lethal infections.

The team, from the Ariel University in an illegal West Bank settlement, were looking for bacteria able to inactivate or evade beta-lactam antibiotics, a major group of vital drugs which includes penicillin, cephalosporin and carbapenems.

They found 35 drug-resistant species in all, while 12 per cent of the animals had at least one species of drug-resistant bacteria, and a quarter had two or more.

“Our findings demonstrate that animals in petting zoos can result in shedding and transmission of multi-drug-resistant pathogens that may cause illness for human visitors, even when the animals appear healthy,” said Professor Shiri Navon-Venezia, presenting the research at the European Congress of Clinical Microbiology and Infectious Disease in Amsterdam on Saturday.

Bacteria found included highly infectious strains of drug resistant E coli, which cause diarrhoea if ingested as well and urinary tract infections.

While healthy immune systems can contend with these invaders, they can turn serious in young children and older people, and may also pose risks to women who are pregnant or people whose immune systems are compromised.

Bacteria are also adept at passing on genes to other species, so once they spread into a new environment other species can rapidly develop resistance.

While inappropriate use of antibiotics in humans – such as prescriptions for viral colds where they will have no effect – is part of the issue, overuse of antibiotics in farming is another major problem.

In many countries, antibiotics are used as a growth promoter in meat production and this creates more pressure on bacteria to develop resistance. Antibiotic residues in wastewater also spread this pressure into streams and other environments.

The report found that drug-resistant strains were particularly abundant in animals that had been treated with antibiotics, and said zoo owners should ensure these animals are not allowed to be petted.

“We recognise the high educational and emotional value of petting zoos for children,” Professor Navon-Venezia said. “Therefore, 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.”

Other measures include prohibiting food and drink being consumed near the animals and regular hand-washing stations. However, another recent study suggested that in hospitals some superbugs are starting to resist even powerful alcohol hand sanitisers.