An adult is hospitalized with rat lungworm disease on Oahu, the first case of the illness contracted on the island since 2010, the Health Department announced Wednesday.

The Oahu resident came down with symptoms in July that were consistent with the parasitic disease, which can affect the brain and spinal cord. It was the 16th laboratory-confirmed case statewide in 2017, following cases on Hawaii island and Maui.

The total so far this year is a jump from the 11 confirmed cases in all of last year, and continues the upward trend from seven in 2015 and four in 2014, according to Health Department records.

“This is a serious disease that can be acquired on any of our islands because slugs and snails throughout the state carry the parasite responsible for the illness,” said Keith Kawaoka, deputy director of environmental health. “This is a grim reminder that we all need to take precautions when working in our gardens and on farms, and eliminate slugs, snails and rats from our communities to reduce the risks posed by this parasitic disease.”

Health officials would not specify where the latest patient lived, and the source of the infection is not yet known. But staff from the department’s Vector Control Program and Disease Investigation Branch began doing property assessments in East Oahu Wednesday morning, looking for slug, snail and rat activity. The case was confirmed late Tuesday.

“For this specific Oahu case, our investigation that our vector staff has done so far, they haven’t found any snails or semi-slugs in the places they were able to observe so far,” said Anna Koethe, public health information coordinator for the Health Department. “We are looking really hard into the patient’s previous history as far as where they traveled and what they ate. It can be hard to recall.”

Typically, it takes one to three weeks after infection for symptoms of rat lungworm to appear. Common symptoms include severe headaches, nausea, neck stiffness, fatigue and pain, although some people show no symptoms. The disease can cause neurological problems and severe disability.

Anyone who believes they may have rat lungworm should see their doctor as soon as possible. Patients can be sick for several weeks or longer. The disease is confirmed through a spinal tap.

People can contract rat lungworm disease, or Angiotrongyliasis, by eating raw or undercooked slugs and snails, as well as freshwater prawns, frogs and crabs infected with the parasite. The lungworm parasite infects rats, which pass it on through their droppings.

Health officials urge the public to inspect and carefully wash all fruits and vegetables, especially leafy greens, under running water to remove any tiny snails or slugs. Thorough cooking prevents infection.

Some observers suggest the spread of the semi-slug is contributing to the rise in cases.

“The presence of the semi-slug definitely has an effect,” Koethe said. “It’s such an efficient carrier of the parasite itself. They do move a lot faster than regular slugs.”

Authorities advise residents to eliminate slugs, snails and rats around their homes and gardens, and to use gloves rather than bare hands when handling them.

People with water catchment systems should cover and protect their tanks to keep slugs from crawling inside, and consumers should also keep food and drink in covered containers, officials said.

Find more information on rat lungworm disease and how to prevent it at 808ne.ws/rat-lung.