Rat Lungworm Disease - Information

Rat Lungworm disease is a parasite that's officially known as Angiostrongylus Cantonensis and is a nasty little creature that can affect the brain and spinal cord. It's clearly something you do not want in your body! But where does it come from? How can you get it? More importantly, how can you avoid it? These are all questions we'll answer right here in our guide to Rat Lungworm Disease in Hawaii. You may also be interested in checking out Hawaii Living: Pests & Traffic.

What Is Rat Lungworm?

I promise not to give you parasites.

As briefly mentioned above, it's a disease that can affect your brain and spinal cord. It is caused by a parasitic nematode (roundworm) that is found in rodents. The rodents can pass the larvae through their feces and then other animals, such as snails and slugs, can become infected when they eat the rat feces. That's right, snails and slugs eat rat feces.

How Can I Get Rat Lungworm?

In Hawaii, snails and slugs are pretty common. Those snails and slugs can get the disease from the feces of rodents who carry the worm. Snails and slugs love plants and moist areas where plants grow (like gardens and farms). If you eat produce (lettuce being especially common) that an infected slug / snail was on then the disease can pass to you if that produce wasn't properly cleaned.

So, eating raw or undercooked snails and slugs is one way. Eating raw produce that hasn't been properly washed is the other way (either by eating a tiny snail or slug that didn't get washed off or possibly from the slime or fecal trail left on the produce). It's also possible to get it from drinking straight from your garden hose (as a snail may have been in there).

What Are Rat Lungworm Stages & Symptoms?

The parasite can only fully mature in rats. Snails and slugs only serve as an intermediate host where the parasite can grow to a point where it is then capable of causing infection but not to full adulthood and thus cannot reproduce.

When the parasite gets into a human it cannot complete its lifecycle (it can only do that in a rodent) and actually gets lost in the human. It tends to go to the brain and stays there. Some people who get the disease actually have no systems while others can become violently ill. When it's in the brain you can develop eosinophilic meningitis which is a swelling of the thin membrane that covers your spinal cord and brain.

Common symptoms may include a severe headache, stiff neck, possible painful or tingling feelings in the skin or extremities, nausea, vomiting, and fever. Some cases have also reported temporary face paralysis and sensitivity to light. Symptoms usually start one to three weeks after being exposed to the parasite but could happen anytime between a day and six weeks after exposure.

Symptoms often last from two to eight weeks. Although most cases of infection are not severe, there have been rare cases that can lead to a coma or even death.

How Is Rat Lungworm Treated?

While there is no cure for the diseases, the most common form of treatment is with antiparasitic drugs, pain medication, and steroids. Because the parasite cannot fully mature in humans it cannot reproduce and thus will eventually die. Until that happens, there can by physical pain and problems. In some cases, the parasite will find its way to the eye where you can develop ocular Angiostrongylus. If that happens it may be possible to surgically remove the worm.

In the best case scenario, patients may experience a mild illness and then get better on their own. Because it's a difficult parasite to detect, doctors rely a lot on the habits of the person who is experience symptoms. In Hawaii, around 80% of land snails are carriers of the parasite (based on a 2014 research paper) so if you're experience symptoms it's important to let your doctor know you've been to Hawaii.

How Can I Avoid Rat Lungworm?

This is the one we all care about, right? Fortunately, preventing Rat Lungworm disease is incredibly easy! First off, stop eating snails and slugs. They're slimy and gross and there is better food out there. I mean, you read the part when I mentioned that they eat rat poop, right? If you must eat them, make sure they are fully cooked. Never eat raw or undercooked snails or slugs. And stop drinking from your garden hose where they may have been hanging out. That's half the battle right there, but it's a war you shouldn't be fighting.

For the other half, simply make sure that you wash all produce thoroughly before eating, especially if you're eating them raw (in a salad, etc). This is usually easy with vegetables like carrots, peppers, and celery (use a scrub brush if you're extra paranoid). Lettuce is the tougher one so to make sure you're lettuce gets extra clean use a Salad Spinner #ad. You plop in your individual lettuce leaves, add water, make it spin. Repeat as needed, dry, and you now have clean lettuce. Do yourself a favor, go buy a salad spinner now #ad, they're inexpensive.

I know what you're thinking now. What about restaurants washing lettuce properly? Well, you're certainly relying on the fact that restaurants know how to properly clean and prepare food. Fortunately, the vast majority of restaurants do. But there are things you can do here as well. First up, understand how Hawaii's Restaurant Grades work. Only visit establishments that clearly display the "green" health inspection sign in their window (which they are required by law to do). If you're still worried you can simply skip the snails and slugs appetizer and the salad as well.