Maui Resident Becomes First Rat Lungworm Disease Case of 2020 in Hawai‘i

Rat lungworm photos: Juvenile Parmarion martensi on a nickel (credit: HDOH); Veronicella cubensis (Credit: Rob Cowie, UH Mānoa)

The Hawai‘i Department of Health has confirmed a case of rat lungworm disease or angiostrongyliasis contracted on Maui. The individual is a resident of Maui and is the first person this year to test positive for the disease in Hawai‘i. In 2019, there were a total of nine reported cases.

The individual sought treatment and was hospitalized at Maui Memorial Medical Center. Officials from the Department of Health say the investigation was not able to identify an exact source of infection.

“In the midst of the COVID-19 situation, we need to also be mindful of other diseases such as rat lungworm,” said Dr. Lorrin Pang, Maui District Health Officer. “With many people starting their own home gardens for self-sustainability, we’d like to remind everyone to thoroughly inspect and rinse all fresh fruits and vegetables under clean, running water. For added prevention, cooking food by boiling for 3 to 5 minutes or heating to an internal temperature of 165 degrees Fahrenheit for at least 15 seconds can kill the parasite that causes rat lungworm disease.”

Angiostrongyliasis, commonly known as 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 (A. cantonensis).

Symptoms vary widely between cases, and the most common ones include severe headaches and neck stiffness. The most serious cases experience neurological problems, severe pain and long-term disability.

The Department of Health offered the following tips on how to prevent rat lungworm disease:

• Control snail, slug, and rat populations around homes, gardens and farms. Get rid of these vectors safely by clearing debris where they might live, and also using traps and baits. Always wear gloves for safety when working outdoors.
• Inspect, wash and store produce in sealed containers, regardless of whether it came from a local retailer, farmer’s market, or backyard garden.
• Wash all fruits and vegetables under clean, running water to remove any tiny slugs or snails. Pay close attention to leafy greens.

Dr. Pang said, “We have been routinely monitoring slug populations in vegetable gardens at a sentinel site on Maui since the earlier part of this year. The counts have remained moderate to high and we are setting up a field intervention study to control the slug population.”

The Governor’s Joint Task Force on Rat Lungworm Disease is in the process of updating guidelines for Hawai‘i physicians, which provide clear diagnosis, treatment, and management guidance for timely identification and care for patients who have contracted the disease. The current guidelines are available at: https://health.hawaii.gov/docd/files/2018/08/RLWD_Preliminary_Clinical_Guidelines_FINAL_082918.pdf

For more information about rat lungworm disease and how to prevent its spread, visit:

DOH website: http://health.hawaii.gov/docd/disease_listing/rat-lungworm-angiostrongyliasis/
HDOA website: http://hdoa.hawaii.gov/blog/main/rat-lungworm-information/
CTAHR website: http://manoa.hawaii.edu/ctahr/farmfoodsafety/rat-lungworm/
CDC website: https://www.cdc.gov/parasites/angiostrongylus/index.html

Video on proper produce washing: http://manoa.hawaii.edu/ctahr/farmfoodsafety/wp-content/food-safety-videos/WashProduce-DOH.mp4