Sharon Redrobe. BSc(Hons) BVetMed CertZooMed MRCVS

Head of Veterinary Services

Bristol Zoo Gardens

UK

Reptiles are becoming increasingly common pets in the UK. There are a growing number of reports, both in the media and the scientific literature, of the role reptiles have in the spread of diseases.

How big is the reptile pet trade?

There is a large international trade in live reptiles. The USA accounts for 80% of this trade recently reaching over 2.5 million reptiles imported in 1995. In the UK, over 10,000 green iguanas were imported per year in the 1990s. A current price list of a reptile supplier to UK petshops has a catalogue of over 100 different species ranging from pythons to turtles. Clearly, reptiles are becoming increasingly popular in the UK and already exist in large numbers. Moreover, many of these animals are not captive bred in the UK but imported from the wild with little attention to preventative treatment or quarantine.

For many commonly kept reptile species the correct husbandry requirements for a long and healthy life are known. Mismanagement unfortunately accounts for many disease problems in captive reptiles. Reptiles are ectothermic and so depend upon the external temperature provided for regulating their internal body temperature and hence homeostatic processes. Below optimum environmental conditions may lead to a depressed immune system, with multiplication and excretion of pathogens.

Salmonellosis probably represents the most important zoonotic disease of captive reptiles. It was estimated that in 1970 approximately 280,000 people in the United States acquired Salmonellosis from contact with aquatic turtles. In the United States, public health significance of this organism has resulted in a ban on the sale of turtles with a carapace length less than 4 inches. Salmonellosis is also associated with keeping snakes and lizards as pets. One of many cases that hit the media headlines in the USA include that of a 21-day old girl from Pennsylvania, who was hospitalised because of an illness that included vomiting, bloody diarrhoea and fever. A faecal culture of stool yielded Salmonella serotype Poona. Other members of the family were asymptomatic. The family -owned iguana had a faecal culture positive for Salmonella serotype Poona. Although the infant had no contact with the iguana, it was handled frequently by her mother.

1. The following categories of people should avoid all contact, direct or indirect, with any reptile- Infants and children up to 5 years of age; Anyone with HIV/AIDS or other disorders or medication that suppresses the immune system; Elderly, frail or people with poor nutritional status; Women who are pregnant due to risk to the foetus.
2. What to do to avoid becoming infected or acting as a carrier. Reptiles should not be kept in child-care centres. Keep reptiles out of kitchens and away from any surfaces where human food is stored, prepared or served. Do not use kitchen sinks to clean reptile accessories or caging materials. Do not permit unsupervised handling of reptiles by children under 12 years old. Always wash hands thoroughly after handling any reptile.

There is also serologic evidence of leptospirosis in free-ranging snakes. This organism is shed in the urine of affected animals. Mycobacterial disease has been reported in snakes and turtles (particularly Asian box turtles) and may be detected in the faeces or respiratory secretions of affected animals.

Many reptile imported into the UK and USA carry ticks. Recent surveillance at a Florida airport found 28% of imported reptile shipments were infested with eight tick species. These include species known to carry Q fever (Coxiella burnetti) a zoonosis, and heartwater (Cowdria ruminatum) an acute tickborne disease of ruminants leading to mortality rates of 40-100%. Despite these findings, no tick control measures on reptile imports have been implemented.

Keeping any pet poses a variety of health risks regardless of whether that pet is a dog, cat, bird, or reptile. Attention to simple hygiene precautions such a handwashing greatly reduce the likelihood of spreading the most likely zoonotic disease, Salmonella, from reptiles to man. Similarly, relatively simple measures such as attention to correct quarantine procedures for recently imported reptiles with appropriate treatment, particularly with regard to the elimination of ectoparasites, would limit the potential spread of exotic diseases to the UK animal population. There is no doubt that such issues will continue to grab headlines and the veterinary profession should ensure it is able to provide accurate advice on the care and treatment of reptile species.

Further information

reptile associated Salmonellosis at the Center for Disease Control http://www.cdc.gov/od/oc/media/fact/salmonel.htm
The website of the British Veterinary Zoological Society contains information for vets and owners on Salmonella in reptiles (visit www.bvzs.org.uk)