Angiostrongyliasis, also known as rat lungworm (RLW), has been in the news a lot recently. Over the past ten years, more than 80 cases of people developing RLW have been reported. Two of the people died from the disease. Some of those who survived have reported continuing effects.
RLW affects the brain and spinal cord. It is caused by a parasitic nematode (roundworm parasite) called Angiostrongylus cantonensis. The adult form of A. cantonensis is only found in rodents, such as rats and mice. Infected rodents can pass larvae of the worm in their kūkae (feces). Then, intermediate hosts which eat the kūkae, such as snails, slugs, freshwater shrimp, coqui frogs, and similar animals can become infected by ingesting this larvae.
Humans can become infected with A. cantonensis by eating a raw or undercooked infected intermediate host, such as a small slug. This is easier to do than one might imagine, as they can be quite small and hide in the folds of leafy greens.
The parasite does not reproduce in humans, but when they are trying to grow, and when they are dying, they can make people very sick.
Pets can be infected with RLW if intermediate hosts such as slugs are crawling on their food, and the pet accidentally consumes the slug while eating.
Eliminating rats and slugs from areas near your home will help to reduce the chance you will come into contact with it. Manu and I have tried many different traps and pest-chasers. We have found the Rat Zapper to be the most effective for getting rid of rats. For slugs, I lay out sheet plastic, then (wearing plastic gloves) “harvest” the slugs from the plastic and squish them. The remains are bagged and disposed of rather than buried, as we do not want pets digging them up.
For more information on the life-cycle of A. cantonensis, visit the CDC website.