LIHUE — Slugs and rats.
Those are the vectors for rat lungworm disease, around which the state has launched a public education and awareness campaign.
It’s a disease that some people don’t even know they have contracted, and one that leaves others with fevers, headaches or temporarily paralyzed — which is a challenge for healthcare professionals working on diagnosis.
“As with many other diseases, persons with milder symptoms may not be present to a doctor and will resolve over time,” said Anna Koethe, spokeswoman for Hawaii Department of Health.
Variable levels awareness and a wide array of symptoms make it even more difficult to pinpoint the disease, even when it’s more severe.
In fact, a spinal tap is really the only way to confirm diagnosis of rat lungworm disease, and not all patients have taken that route.
Knowledge is key
Rat lungworm disease is caused by a parasite that hatches from eggs inside rodents. The parasite larvae are passed out of the rodent body through feces, and then they move to their next host: mollusks.
Snails and slugs are infected by first-stage larvae and they become the intermediate hosts for the parasites. After two molts, the larvae reach the infective stage.
Humans who eat food containing the third-stage, infective larvae become infected with the parasite. That food includes the uncooked mollusks themselves, or vegetables contaminated with snails and slugs or their slime.
Crabs and freshwater shrimp can also be hosts, according to the Center for Disease Control.
In 2017, there were a total of 18 laboratory-confirmed cases of rat lungworm disease statewide, confirmed with a lumbar puncture sample. Of those 18, all but one were adults.
In September 2017, DOH confirmed a case in an infant from the Puna District of Hawaii Island. After an investigation, DOH learned the infant likely became infected after accidentally eating a slug or snail.
In addition, there were three statewide probable cases in 2017, which means symptoms and background history and other lab tests were consistent with infection.
Since 2007, when rat lungworm disease became reportable to DOH, 45 cases have been confirmed and 37 probable cases have been reported.
On Kauai, there were no confirmed rat lungworm disease cases in 2017. In 2016, there was one probable case in a resident and in 2015 there was one case confirmed in a visitor to the island, according to DOH.
But prevention education was conducted for farmers and growers across the island in 2017 in order to boost awareness. Presentations on the disease were also given to Kauai County department heads, the County Council, and other regulatory offices across the island in 2017.
“Community education is conducted regularly at health fairs, farmers markets and other events around the island, such as Kauai Farm Fair and Arbor Day,” Koethe said.
The goal is to arm Hawaii’s people with the knowledge they need to protect themselves from the disease.
Hawaii’s Department of Agriculture is also part of the education effort, and the entity ran Public Service Announcements in 2017 to help bolster awareness.
“One PSA was directly for RLWD (rat lungworm disease) which ran for two months, June and July 2017,” said Janelle Saneishi, spokeswoman for HDOH. “We also ran three food safety PSAs aimed at agriculture from September through December on Spectrum Cable.”
Currently, HODA is in determining if there’s enough money left in 2018 to do additional runs of the last three PSAs that were released.
“While we don’t have any data available on whether growing awareness has materialized into a decrease in cases, we do hope people are more aware and taking proper steps to prevent the spread of the disease,” Koethe said.
As awareness increases and the public becomes educated, health officials are preparing for an uptick in cases because as more people become aware of the disease, they are more likely to visit a doctor.
“Likewise, with awareness growing in our medical community, we believe a growing number of doctors are more likely to recognize the symptoms and take proper steps to provide proper diagnosis,” Koethe said.
Visitor awareness
While most of the educational information is directed at residents, DOH is working with Hawaii Tourism Authority to provide critical updates to visitors.
For instance, two monitors in Honolulu’s Daniel K. Inouye International Airport, donated by the CDC, warn travelers of potential health risks, such as rat lungworm disease.
Since 2007, there have been four confirmed visitor cases and one probable case of rat lungworm.
A probable case was reported in 2009 on Hawaii Island. There was one confirmed visitor case on Kauai in 2015, one confirmed visitor case on Hawaii Island in 2016, and two confirmed visitor cases on Maui in 2017.
“We know that many visitors and residents frequent malls across the state. We’ve worked to place large-scale graphic advertisements with rat lungworm disease prevention information, including Kukui Grove on Kauai,” Koethe said.
Prevention
It takes actually rinsing and removing contaminants in order to prevent rat lungworm disease, and it doesn’t really matter what kind of soap-like product is used, according to studies from the University of Hawaii.
That research has shown that thoroughly rinsing and rubbing produce under clean, potable, running water is the most effective way to remove slugs, snails and other contaminants from fruits and vegetables.
“Careful attention should be paid to leafy greens, which should be rinsed leaf by leaf and inspected before eating,” Koethe said.