Group creates rules for faster diagnosis of rat lungworm

A group commissioned by Gov. David Ige has created guidelines for earlier diagnosis and prevention of the potentially crippling rat lungworm disease.

The Joint Task Force on Rat Lungworm Disease announced Thursday a plan to train doctors statewide on detecting angiostrongyliasis, or rat lungworm, following the fifth confirmed case this year in a toddler from East Hawaii.

Many local physicians are unaware of the symptoms associated with the disease, delaying treatment for some patients.

Doctors are now being advised to follow specific guidelines that include the use of the controversial anti-parasitic drug, albendazole, along with steroids to prevent inflammation. They are also being asked to encourage patients with symptoms to get a spinal tap, or lumbar puncture, for timely diagnosis.

“There were no clear, reliable diagnosis and treatment protocols available to Hawaii physicians for this potentially serious and debilitating disease,” task force member Dr. Vernon Ansdell, an associate professor at the University of Hawaii John A. Burns School of Medicine, said in a news release. “Diagnosing angiostrongyliasis can be problematic because patients infected with the parasite do not always present the same symptoms. These preliminary guidelines provide critical guidance to physicians to help them make timely and accurate diagnoses and give their patients the best possible treatment available.”

Last year there were 18 confirmed cases of rat lungworm, most of them on Hawaii island. Patients often start with nonspecific symptoms such as fleeting pain, tingling and numbness in the limbs, headaches and weakness. Within a week or so, symptoms become more severe as the parasite travels into the brain and damages nerves. Other symptoms include stiffness in the neck and neurological problems that can result in long-term disability. Until now state Department of Health officials advised against the use of anti-parasitic medications, saying there was no credible evidence that they actually helped.

“The concern is that you’re killing the parasite, and by doing that you’re creating this inflammatory response in the brain. But the key thing is if you do use that drug, you combine it with steroids that reduces the inflammation,” Ansdell said. “We’re not saying you should use anti-parasitic drugs all the time, but take it into consideration, particularly if you get patients diagnosed early. It’s always a personal judgment based on case by case.”

The new guidelines come after reports of some Big Island patients taking sheep dewormer medication to treat rat lungworm symptoms, according to Ansdell and one Hawaii island patient.

“It just reflects that people are very frustrated. We’re hoping by educating the medical providers across the state, we can help get rid of that sort of issue,” he said. “Any time people try and treat themselves without the backup of a medical expert, it is potentially very dangerous.”

The group spent about a year researching human studies and best-treatment practices from experts around the world before crafting Hawaii’s preliminary guidelines, he said. The next step is training doctors in all counties on recognizing the disease. Doctors will be offered continuing medical education courses through JABSOM starting in Hilo on Oct. 10. Courses will also be offered on Maui, Kauai and in Honolulu in early 2019.

Rat lungworm, first detected in Hawaii in 1960, is poised to expand throughout the tropics and mainland as temperatures warm, according to UH researchers. Rats are the primary hosts, while snails and slugs are considered intermediate hosts that can hide in produce, water catchment systems and garden hoses unbeknownst to the victims who accidentally ingest them.

The Legislature last year granted the Health Department $1 million over two years to help control the spread of rat lungworm. Health officials also are working with experts to develop guidelines for schools, farms and food establishments.

The DOH recommends controlling the population of snails, slugs and rats around homes, gardens and farms, as well as carefully inspecting and washing produce.