LIHUE — New research from the University of Hawaii at Manoa shows the parasite that causes rat lungworm is on at least five of the six largest islands in Hawaii, including Kauai.
The study also reveals the parasite’s distribution may expand into higher elevations as the climate warms and could expand globally in tropical, subtropical and temperate regions.
The data will be important to the state Department of Health in targeting epidemiological surveys and interventions, according to researchers.
“Local residents and visitors need to know what the risks are,” said RobertCowie, senior author on the study and a research professor at the UH Manoa Pacific Biosciences Research Center in the School of Ocean and Earth Science and Technology.
Cowie continued: “Also, remember that it is not possible to say that rat lungworm is absent from locations where we did not detect it. One can never do a totally comprehensive survey of all snails present in Hawaii, so people must not be complacent and assume, for instance, that based on this study rat lungworm is not in their yards.”
The study screened 1,300 snails and slugs from 37 species at almost 200 sites across the Hawaiian Islands using molecular techniques and then developed mathematical models to predict likely areas where rat lungworm could occur, if it isn’t there already.
Research also indicated rat lungworm tended to occur in warmer and rainier locations generally, but not exclusively, windward.
Knowledge of where rat lungworm is or could be across the Hawaiian Islands is important from the perspective of prevention of human and animal infection, according to UH.
The parasitic nematode that causes rat lungworm uses rat, snail and slug digestive systems to continue its lifecycle. The parasite is deposited onto vegetables, fruits and other plants by slugs and snails and then can be transferred to humans.
Human infection by this parasite is considered an emerging infectious disease according to UH and the range and incidence of the disease are expanding throughout the tropics and subtropics, including in the Hawaiian Islands.
Symptoms include severe headache and stiffness of the neck, tingling or painful feelings in the skin, low-grade fever, nausea and vomiting, according to the state Department of Health.
Temporary paralysis of the face and light sensitivity may also occur.
Lead author of the study as a UH graduate student, Jaynee Kim, said helping to inform the public was a main motivation for the study.
“We encourage the public to buy local and support Hawaii‘s economy but, at the same time, to be vigilant about washing produce, especially to inspect and wash greens leaf by leaf. Buying and planting native plants instead of non-native plants can also help keep invasive snail hosts from being introduced and spread throughout the islands,” Kim said.
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Jessica Else, environment reporter, can be reached at 245-0452 or at jelse@thegardenisland.com.
