Travellers to the Canaries, Balearics and Valencia on mainland Spain should be aware of an emerging new zoonotic disease that – in very rare cases – can lead to coma and death in humans.
It’s called rat lungworm, and it’s caused by a parasitic nematode worm with a complex life cycle that infects gastropods such as slugs and snails (but also marine invertebrates such as prawns) and then secondary hosts such as rats.
Humans and dogs can pick it up by eating uncooked infected hosts or accidentally consuming rat faeces. Symptoms – though rare – can include severe headaches, stiffness in the neck and back and sensitivity to light, and they can lead to the victim falling into a coma and even dying.
Though the parasite Angiostrongylus cantonensis was first discovered in China in the early 20th century and is largely associated with Southeast Asia, India and the Pacific Islands, in the past decade it has been found in rats on Tenerife in the Canary Islands, hedgehogs on Mallorca in the Balearics and (again) rats in and around the port of Valencia on mainland Spain.
The discovery of A. cantonensis in Valencia shocked researchers. “This is the first of its kind in continental Europe and could pose a public health challenge to most European countries and the world at large if no proper measures are put in place to quickly mitigate its spread,” they wrote in a paper in the International Journal of Surgery. More research into the prevalence of the disease in wildlife should be carried out, they added.
Scientists have also found rat lungworm infections in dogs are increasing on Australia’s east coast. A new paper found there were 32 cases in 2022, mainly around Brisbane and Sydney, with peak incidence in the autumn, at times of optimal temperature and moisture conditions for snail and slug activity.
Infected dogs exhibit a range of symptoms such as hindlimb and tail paralysis, urinary incontinence and being overly sensitive to touch. "Dogs serve as a critical sentinel population for humans, experiencing significantly higher infection rates that provide an early warning of emerging human risks,” the paper in The Journal of Infectious Diseases warned.
There is no suggestion at this stage that the disease has found its way to Britain, but the British Pest Control Association says climate change and globalisation are contributing to its spread across the world. Its advice to prevent infection is to thoroughly wash raw fruits and vegetables and cook any molluscs (or similar food stuffs such as prawns and shrimps) well before eating them.
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