Lizard and Snake Zoonoses

Lizards and snakes present problems to handlers and owners not just because of their venom and size but also due to the possibility of zoonosis. Care must be taken with all lizards when they are handled even if they are not perceived as dangerous. Consider the following points.

Zoonoses

The common zoonosis associated with reptiles is salmonellosis. Subclinical infections of reptiles are common and Salmonella spp. can often be isolated from faeces. However, most reptiles naturally carry these bacteria as a component of their indigenous gut flora, and they are rarely a cause of primary disease. Over 2400 different serotypes of Salmonella spp. are known and all should be considered pathogenic. Shedding of Salmonella organisms can be intermittent and therefore all reptiles should be considered positive and managed appropriately, regardless of fecal culture results.

• Pregnant women, children under five years and immunocompromised persons should avoid contact with reptiles and reptile implements.
• The CDC recommends that reptiles should not be kept in child-care centres and households in which persons at risk reside.
• Provide information to potential purchasers and owners about the risk of acquiring Salmonella.
• Proper hygiene measures should be conducted around reptiles at all times in order by reducing exposure to faeces of infected animals.
• Reptiles should be kept out of sites where potential for transmission exists.

Salmonella spp. are the most important zoonotic agent. Reptiles can also harbour several different opportunistic Gram-negative bacterial pathogens that can infect humans. These include Aeromonas, Campylobacter, Enterobacter, Klebsiella, Erysipelothrix rhusiopathiae, Pseudomonas, Mycobacterium spp., Coxiella burnetti, Chlamydophila psittaci, Aspergillus, Zygomycosis, Candida, Trichosporon, Trichophyton and ticks. These potentially zoonotic diseases can be managed by practicing routine hygiene practices.

Hygiene

The majority of reptile-related salmonellosis reported in humans could be avoided if common sanitary practices are followed. Washing hands with soap is an effective method to remove Salmonella spp. organisms and minimize contamination of the environment. This should always be carried after handling any animal. Disinfectants, such as sodium hypocholorite, should be used to disinfect the reptile enclosure including food and water dishes, and other cage furniture. Gloves should always be worn, and cleaning should not take place in the kitchen or bathroom.

For more information, see lizard and snake day to day practice and quarantine.

Useful resources

• Zoonoses - WHO