Scientists warn of danger of pets

20:41, Nov 12 2012

The health risks pets pose to their owners is poorly monitored internationally, raising the risk that diseases transmitted from cats and dogs will cause outbreaks in humans, scientists warn.

Cats and dogs closely shared the domestic environment with people and had the potential to act as sources of a wide spectrum of zoonotic infections - those which can be transmitted between animals and humans, the scientists said in a review published online in Emerging Infectious Diseases.

"Small companion animals might play a major role in potential zoonoses of the future, either by acting as a reservoir or as an intermediate host. Information about known and potential zoonoses associated with cats and dogs is emerging rapidly and needs to be more efficiently disseminated."

The authors of the review, led by Bristol University professor of veterinary pathology Dr Michael Day, are members of the World Small Animal Veterinary Association one health committee which seeks greater integration of human and veterinary medicine.

The review said it had been found that about 75 per cent of newly reported human infections had emerged from animal reservoirs.

While many systems were in place to monitor human and production animal diseases, and to a lesser extent human and wild animal diseases, there was a lack of co-ordinated global surveillance schemes monitoring disease in small companion animals, the review said.


It acknowledged that cats and dogs had played an integral role in many aspects of human life for thousands of years, but added: "This bond with pets has strengthened over the past 50 years. The cat and dog have moved from the barn, into the house, and now, routinely, into the owner's bed."

Recent estimates suggested 72 million pet dogs lived in the United States in 37 per cent of households, while 81 million pet cats were kept by 32 per cent of households.

Risks for transmission of infectious diseases were compounded in many developing cultures by generally poor or nonexistent veterinary care.

"More problematic is the vast number of free-roaming or community-owned dogs and cats that receive even less veterinary medical attention and provide a potential huge and uncontrolled reservoir for existing and new emerging zoonoses," the review said.

Another concern was the transfer of infectious agents between wildlife, such as rodents, and domestic cats and dogs.

Rabies was an example of a disease that could be transmitted between people and animals. Each year it was thought to be the cause of the deaths of an estimated 55,000 people in parts of Africa and Asia. Primarily people became ill after being bitten by dogs and becoming infected with canine rabies.

Urgent action was needed to establish a global infectious disease surveillance system that included small companion animals, the review said.

The hurdles to such a scheme were challenging, with a fundamental issue being who would assume the leadership responsibility to plan for such a system. It also presented a major political, scientific and financial challenge.