Zoonotic Parasites of Reptiles

Reptiles have been generally associated with bacterial zoonotic pathogens, such as Salmonella, but reptile-borne parasitic zoonotic diseases have received little attention over the past years.

As other animals, reptiles are hosts of several pathogens. The zoonotic risk is associated with human-reptile interactions such as reptile meat consumption, keeping reptiles as domestic animals or environmental contamination.

The majority of human infections by pentastomids occur through the oral route by ingesting snake meat – more frequently in Asian and African countries. However, alternative transmission routes have been described, such as contact with snake nasal secretion, saliva, and feces.

There are also many hematophagous arthropods (such as species of Ixodidae and Argasidae) that ingest reptile blood and then feed on humans and other mammals, acting as mechanical vectors of pathogens. Among the examples, the authors highlight phlebotomine flies (mainly of the genus Sergentomyia), that are nowadays associated with the transmission of pathogenic species of Leishmania. Other pathogenic species besides Leishmania infantum and Leishmania major have been detected in lizards, suggesting those could be part of the epidemiological cycle of leishmaniasis.

Amphibians and reptiles are also paratenic hosts of nematodes with zoonotic potential. Trichinella encapsulated species have been documented in mammals, but two nonencapsulated species can also be found in large carnivorous reptiles, like crocodiles and monitor lizards.

Reptiles are commonly kept as pets, from ball pythons to green iguanas or tortoises. Most of them live in poor husbandry conditions, which facilitates organic imbalances and leads to a bigger need of medical care. A regular veterinary check-up and attentive veterinarians are essential to prevent infections amongst pet owners, especially those who are immunosuppressed.

Awareness of zoonotic parasitosis with origin in reptiles is important to promote control, prevention, and surveillance of these diseases. To minimize the risk of zoonotic pathogen transmission, preventive measures should be taken into hand: proper sanitary precautions, personal hygiene, good husbandry conditions and regular veterinary assistance.

Mendoza-Roldan J.A., Modry D. and Otranto D. (2020) Zoonotic parasites of reptiles: a crawling threat. Trends in Parasitology, Vol.36, No.8. https://doi.org/10.1016/j.pt.2020.04.014