Rat lungworm disease detected in adult on Kaua‘i

A case of neuroangiostrongyliasis, or rat lungworm disease, was identified in an adult on Kaua‘i for the first time since 2019.

The individual experienced symptoms including headaches, nausea, vomiting, neck stiffness and photophobia (aversion to bright light) and sought medical care, according to a news release from the Hawai‘i Department of Health. The diagnosis of rat lungworm was confirmed by newly available sensitive testing at the department’s State Laboratories Division.

The investigation was not able to identify an exact source of infection.

Rat lungworm disease is known to be endemic in all islands of the state of Hawai‘i. This individual had no history of travel to other neighbor islands or outside the state or country, according to health officials.

From Jan. 1, 2014, to the present, 102 cases of rat lungworm disease have been reported statewide — 78 from Hawai‘i County, 13 from Maui County, seven from Honolulu County and four from Kaua‘i County (including the case reported in this release). Hawaiʻi residents make up 84% of that count, with the other 16% of cases reported in visitors.

Seventy-three percent of those with a laboratory-confirmed diagnosis were hospitalized.

Rat lungworm disease is caused by a parasitic roundworm and can have debilitating effects on an infected person’s brain and spinal cord. In Hawai‘i, most people become ill by accidentally ingesting a snail or slug infected with the parasite Angiostrongylus cantonensis. Symptoms vary widely between cases; the most common ones include severe headaches and neck stiffness. The most serious cases experience neurological problems, severe pain and long-term disability.

“Thoroughly inspecting and washing all fresh fruits and vegetables under clean, running water is the most effective way to reduce the risk of rat lungworm disease,” said Dr. Sarah Kemble, state epidemiologist. “Small slugs and snails on produce can be difficult to see. Cooking food thoroughly also kills the parasite that causes rat lungworm disease.”

The Department of Health also offered these recommendations to prevent coming in contact with the illness:

• Control snail, slug and rat populations around homes, gardens and farms. Get rid of snails, slugs and rats safely by clearing debris where they might live. Consider using traps and baits.
• Maintain water catchment systems and replace filters regularly. Cover and protect catchment tanks, as slugs can crawl up the tank and get into the water.

For more information about rat lungworm disease and how to prevent its spread, visit: https://health.hawaii.gov/docd/disease_listing/rat-lungworm-neuroangiostrongyliasis/.