Different types of pet lizards
Nobody likes to think about it, but the truth is that any pet animal has the potential for carrying a disease that could be contagious to humans. A disease that is contagious from an animal to a human is called a zoonosis (or zoonotic disease). For example, you might have read about the possibility of green iguanas carrying the potentially dangerous bacterium, Salmonella. Let's separate fact from fiction and learn about the zoonotic diseases of reptiles and amphibians, and how to prevent herp-related illness in your family.
To minimize the risk of contracting a disease from a pet reptile or amphibian, always purchase domestically bred and raised animals only. The reasons for this are simple: captive herps bred in this country are usually housed and bred in much cleaner conditions than their wild counterparts (which means less risk of parasites or organisms that might cause disease). They are subject to much less stress and crowding than wild-caught herps are, and domestics are not subject to poor conditions (such as incorrect temperature, crowding, poor diet) that may occur during importation to this country.
In addition to always purchasing domestic stock, choose herps that appear healthy, and have new pets examined by a herp vet. If your vet recommends testing, be sure to have those performed.
The risk of contracting a disease from a reptile or amphibian is generally small, as long as owners practice good hygiene. However, people with a suppressed immune system are more at risk than the general population. For example, children under 10 and the elderly are considered to be at higher risk. People with chronic disease that compromises the immune system are also at greater risk, as are people with AIDS. People who have had organ transplants, and those taking immunosuppressive drugs (such as prednisone or dexamethasone) are also more susceptible to infection.
Probably the most recognized zoonotic disease is Salmonellosis, caused by the Salmonella bacterium. There are over 2000 different strains of the organism, and there is a different one (or several) that can be found in just about every animal species! But any strain (officially called a serotype) can cause disease in any animal, and virtually all serotypes should be considered to be potentially dangerous to animals and humans.
The problems associated with pet reptiles and Salmonella first came to light in 1963, when a pet turtle was implicated in the disease found in a 7-month-old baby. In 1975, the FDA ruled it illegal to sell turtles with a carapace (upper shell) length of less than 4 inches (with exceptions made for educational or scientific institutions and marine turtles). This law was enacted because baby turtles are much more likely to shed Salmonella bacteria and because it was assumed that larger turtles were less likely to be purchased or handled by young children (who are more at risk).
There are several problems associated with this unusual group of bacteria. First, it can be difficult to diagnose. While this bacterium usually inhabits the gastrointestinal tract, it is not always passed in the feces. So, performing one fecal culture isn't always helpful. If the culture does not show the presence of the bacterium, it doesn't mean that the herp doesn't harbor the organism. In other words, a negative culture result does not rule out the disease. Sometimes, multiple cultures may be necessary to diagnose Salmonella. Other diagnostics may be employed to try and diagnose this disease. Another problem is that the Salmonella bacterium isn't like most other bacteria that can simply be treated with a 10-day course of antibiotics. By treating with antibiotics, instead of eradicating the bacterium, it is possible to create an animal that becomes a carrier, able to shed the organism during times of stress. It is impossible to tell if a reptile is harboring Salmonella simply by looking at it.
The best way to deal with the entire issue of Salmonella is to treat each reptile as if it is carrying the bacterium. By taking certain precautions, you can minimize the risk of actually acquiring an infection from a pet herp. Make sure everyone in the family knows that they must wash their hands after handling a herp. Wear gloves and face protection when washing herp cages, supplies and soaking pools. Use a safe disinfectant (ask your vet) frequently and correctly. Supervise young children around reptiles. Never clean reptile equipment or cages in a kitchen or bathroom used by humans. Don't soak herps in tubs, sinks or showers used by humans. Keep herps out of the kitchen and bathroom. Make herp cages simple to clean and disinfect. Keep other pets away from herps. And finally, no matter how much you may care for your pet herp, never kiss it (and make sure that your children know this rule, as well!)