Ranavirus is a enveloped double-stranded DNA virus and belong to the family Iridoviridae. They are found worldwide and have a very wide host range infecting different animal species and even classes. Transmission is by direct contact, environmental contamination or cannibalism (or eating infected animals).
In amphibians, ranaviruses are increasingly detected and can cause systemic disease and mass mortality in these animals. A distinction is made between the haemorrhagic and the cutaneous form. Clinically, erythema, especially on abdomen and upper legs, ulceration on the toes, and increased endency to bleed are seen. Some animals die without having appeared ill, while others can be inapparent carriers.
In reptiles, ranavirus occur especially in chelonians, where they are associated with stomatitis, rhinitis, pneumonia and liver disease. In lizards, ranavirus seem to have a role in skin lesions, stomatitis, granulomatous changes and mass mortality. The clinical symptoms of snakes are reported as stomatitis, granulomatous changes and liver inflammation.
Ranavirus is also found in fish. In fish, the infection can extend from clinically inapparent to systemic disease with mass mortality.