Killer Snails: What They Are and Why They Are Dangerous for Dogs

A new threat to pet health has emerged in Australia: the so-called “ killer snails ”. The rapid increase in cases has alarmed veterinarians and health authorities, who are calling for greater vigilance and preventive measures to be taken to protect our four-legged friends. Here's what they are and what you need to know.

Australia has seen a rapid spread of the so-called “killer snail,” which carries the rat lungworm (Angiostrongylus cantonensis), as highlighted by recent research from the University of Sydney. Researchers analyzed 180 samples from dogs suspected of infection between 2020 and 2024, confirming 93 cases mainly in the Sydney and Brisbane areas, with a gradual increase and a peak in 2022 related to heavy rainfall that favors the spread of the snails.

Matteo Bassetti, director of Infectious Diseases at the Policlinico San Martino in Genoa, explained that giant snails, originally from Africa, can transmit this parasite, which is also dangerous for humans , as it can cause serious meningitis. Recent heavy rains have favored the proliferation of snails, especially between Sydney and Brisbane.

The rat lungworm, originally from Southeast Asia, has spread to many regions of the world, including North America, Europe, and Australia. Wild rats are the natural hosts, while snails and slugs serve as intermediate hosts. Infected rats release larvae in their feces, which are ingested by snails and slugs. Dogs and people become infected by eating infected snails or vegetables contaminated with parasitic slime.

Dangerous 'killer' snails: symptoms and precautions to take

Bassetti stressed that angiostrongyliasis is a globally emerging disease , favored by its geographic spread due to globalization, and called for international collaboration to monitor the situation . In humans, it manifests as eosinophilic meningitis with symptoms such as headache, neck stiffness, fever and nausea , and in rare cases can cause severe brain damage or be fatal. In dogs, symptoms include paralysis of the limbs and tail , incontinence and abnormal pain, with an incubation period of one to two weeks.

Health authorities recommend taking some precautions to reduce the risk of infection. It is important to wash fruits and vegetables thoroughly before eating them, avoid dogs eating snails, slugs or wet grass, especially in parks after rain, and limit direct contact with snails or frogs, especially in rural or tropical areas.