What Is Rat Lungworm? Toddler Contracts Fifth Case of Disease in Hawaii This Year

A toddler has contracted rat lungworm disease in Hawaii, taking the total number of cases in the state this year to five, health officials confirmed on Thursday.

The child became ill in late July and was seen by doctors in a local emergency room last week, before being hospitalized for several days. Their symptoms improved, and they were eventually discharged, according to the Hawaii Department of Health (DOH).

Lab results later confirmed that the child's illness was caused by the rat lungworm parasite (Angiostrongylus cantonensis), which in its adult form only lives in rodents. Its larvae is excreted in the rodents' feces, going on to infect snails, slugs and other animals—such as freshwater shrimp, crabs or frogs—which come into contact with it.

People can be infected by intentionally or accidentally ingesting uncooked snails or slugs containing the larvae, or eating unwashed food produce, such as leafy vegetables, which contain small snails and slugs, or parts of them. The parasite cannot be spread between humans.

It's possible that eating undercooked or raw animals containing the parasite other than slugs and snails could also lead to infection, however, the evidence for this is not as clear.

"Some infected people don't have any symptoms—or have only mild symptoms that don't last very long," according to the Centers for Disease Control and Prevention (CDC). "Sometimes the infection causes a rare type of meningitis (eosinophilic meningitis). The symptoms can include headache, stiff neck, tingling or painful feelings in the skin, low-grade fever, nausea and vomiting."

In severe cases, which are rare, the disease may lead to long-term neurological damage and disability.

DOH investigators are currently in the process of conducting a detailed investigation to learn more about the patient and possible sources of infection.

"Our children move quickly and are naturally curious about the world around them, which is a normal part of their early development," Aaron Ueno, Hawaii Island District Health Officer, said in a statement.

"We can reduce the risk of rat lungworm disease by controlling slugs and snails around our homes and gardens, and by keeping children away from these harmful vectors as much as possible. The risk of rat lungworm disease exists statewide, and we can work together to take steps to prevent it in our communities."

In addition, officials recommend inspecting and washing all fruits and vegetables—especially leafy greens—under clean running water, regardless of whether it came from a local retailer, farmer's market or garden.

Most known infections of the parasite occur in parts of Asia, the Caribbean, Africa and the Pacific Islands. While several cases have been documented in Hawaii, very few have been reported in the continental United States.

What Is Rat Lungworm? Toddler Contracts Fifth Case of Disease in Hawaii This Year | Health