Aussie dog owners on high alert for dangerous parasite spread by slugs Killer parasites on the rise in Australia READ MORE: Man becomes a paraplegic after swallowing a garden slug By MATT JONES FOR DAILY MAIL AUSTRALIA Published: 03:49 BST, 18 June 2025 | Updated: 03:50 BST, 18 June 2025 Aussie dog owners should remain on high alert for a dangerous parasitic disease that cause a lethal brain infection in both dogs and humans. Rat lungworm disease is a rare but life-altering infection caused by larvae of the parasitic worms found in feral rats and spread by snails and slugs. University of Sydney veterinary researchers are reporting a rise in cases in Sydney and Brisbane following heavier-than-usual rainfall. Up to 93 cases of rat lungworm have been recorded in the five years to 2024 with the risk of infection highest between two and 10 months after heavy rain. Dogs can become paralysed or die if they eat an infected snail or slug. Two Australians have died from the disease to date, including Sydney rugby player Sam Ballard who died after eating an infected slug as a dare in 2010. Mr Ballard suffered a severe brain infection and fell into a coma for 420 days. He died in 2018, at the age of 28, following an eight-year battle with the disease. Rat lungworms (pictured) can have potentially harmful affects in humans if consumed Sam Ballard (pictured) fell into a 420 day coma after eating a garden slug as a dare Mr Ballard (pictured left) died after an eight-year battle with the disease 'These snails and slugs, and the infective worm larvae in them, can accidentally be a disease source to us humans and our pet dogs,' researcher Jan Šlapeta said. 'Once in humans or dogs, the worms quickly get to the brain where they cause disease.' People are only at risk if they eat an infected snail or slug, like Mr Ballard did, or consume the slime left behind on lettuce and other raw produce. Most people infected with the disease can recover without treatment over days, weeks and months but for some it can be catastrophic. The disease can cause severe meningitis and in rare instances be fatal. NSW Health has advised Australians wash fresh produce before eating and to wash their hands after gardening or handling snails or slugs. There have been 28 human cases between 1971 and 2018, and most people were infected from eating unwashed lettuce or vegetables. The mortality rate was 18 per cent, 14 per cent suffered long-term neurological issues and 57 per cent made a full recovery. Share or comment on this article: Aussie dog owners on high alert for dangerous parasite spread by slugs Add comment