Kana Covington had a worm in his left eye. He had to go all the way to Phoenix to find an eye surgeon willing to remove it, because doctors in Hawaii wouldn’t recognize the test that detected it. Now, thanks to a budget dispute at the Hawaii Legislature, the test that got him diagnosed may never reach the general public.
Covington, who lives on the Big Island. is a victim of rat lungworm disease.
The Big Island resident believes his nightmare began about two years ago with what he thought then was a “really strange flu” that involved body aches but no stomach or respiratory problems. Then he began noticing flashes of light and “floaters” in his eye.
He saw three different doctors in Hawaii; they prescribed eye drops, antibiotics and steroids and ran a battery of tests for everything from tuberculosis to HIV. All came back negative.
Covington heard from friends about a program run by Dr. Susan Jarvi and the University of Hawaii Hilo’s Rat Lungworm Working Group involving an experimental blood test for rat lungworm. He volunteered for the test group — and the test came back positive.
But the retina specialist he was seeing in Honolulu dismissed the test results.
“I got the feeling that he didn’t have any answers at all,” recalls Covington.
Relatives helped connect him with a specialist in Phoenix who was willing to consider the rat lung disease diagnosis. Since then, Covington has had three eye surgeries — including one that extracted a worm, confirming the diagnosis.
He the prospects for regaining vision in the eye are “iffy.”
Covington is far from alone among rat lungworm victims who’ve had trouble convincing their doctors. Symptoms vary wildly, from barely noticeable to headaches so excruciating that one woman called the pain worse than childbirth.
The disease is caused by a tiny parasitic roundworm that normally lives out its life cycle in rats and in mollusks such as slugs or snails. Instead of metamorphosing like insect larvae, rat lungworm larvae just change into other forms of larvae and change hosts, moving (normally) from rats to slugs, then back to rats.
So far as scientists know, the larvae can infect humans only during the stage when they leave their mollusk hosts. At that point, if ingested in contaminated produce, they can burrow from the human digestive tract up through liver and lungs to the brain.
Currently, the only official way to confirm the disease is through a painful spinal tap that physicians may be reluctant to approve.
Because of Covington’s experimental blood test and his out-of-state surgery, his case is still not listed among the 18 officially diagnosed cases of rat lungworm in Hawaii this year. And the blood test study that gave him that initial diagnosis, as well as the rest of the Rat Lungworm Working Group’s projects, may soon cease to exist. Jarvi’s lab currently has a remaining budget of about $11,000.
Last year Sen. Kai Kahele of Hilo introduced Senate Bill 272, to fund the lab, which has operated so far on a shoestring budget of small grants, donations and Jarvi’s professorial salary.
“The bill went through House and Senate without a ‘no’ vote,” says Sen. Russell Ruderman of Puna. But apparently Kahele ran afoul of the Ways and Means Committee’s then-chair, Sen. Jill Tokuda, who refused to fund the bill.
Instead, WAM gave a million dollars to the Department of Health, which will be working with the Department of Agriculture over the next two years “to educate people about prevention and to raise the safety and quality-control standards followed by our farmers, retailers and food establishments so that we can continue to buy local, while taking basic precautionary measures to safeguard consumers,” Gov. David Ige announced in an online news conference.
That approach, however, may have two weaknesses. First, the agencies’ mandate contains a conflict of interest: they’re tasked not just with preventing the disease, but with convincing consumers to “continue to buy local,” as the governor put it.
That’s a problem, especially on the Big Island, where most of the diagnosed cases have occurred (though this year has also seen cases on Maui and Oahu). A Facebook query brought dozens of responses from residents who said they’d stopped buying local greens or eating salads at local restaurants because of the disease.
The second problem: so many gaps in knowledge about the disease exist that some of the “education” has outstripped the science.
One Department of Agriculture informational spot, for instance, assures listeners that rat lungworm is “easily prevented simply by washing your produce thoroughly and making sure you don’t consume slugs and snails.” The video accompanying the narration shows a pair of hands rubbing leaves of lettuce together under running water. Near the end, the logo “Clean, Healthy and Locally Grown” appears in bold letters across the bottom of the screen.
“The DOH literature so far still says to wash them in water,” Jarvi said. “There’s no evidence that water kills the larvae. They live quite well in water for weeks.”
One of her lab’s projects has been identifying safe vegetable washes that would kill the larvae; until that study is finished, she says, the public won’t know how to safely clean fresh veggies.
The official literature still claims that the disease is foodborne. But Jarvi has heard from several victims in the Big Island’s Puna District, where the majority of the confirmed rat lungworm cases occurred, who believe that they got ill not from accidentally eating slugs, but from drinking catchment water.
County water is not available in most of the district’s subdivisions. Instead, they rely on catchment tanks — usually repurposed above-ground swimming pools or livestock tanks with cloth covers.
“We’ve seen very well-maintained catchment tanks and if you remove the cover, you’ll find dozens of slugs in there,” Jarvi says.
Many Puna residents drink catchment water that’s been run through filtration systems. Jarvi’s group has gotten a $35,000 Karassic Family Foundation grant to test those filters. They’ve found that the larvae pass easily through 20-micron filters, which many homes have. They’ve just begun testing 5-micron filters. Those, and 1-micron filters, should be fine enough to keep the parasites out — ”theoretically.”
“These larvae can bore, and we don’t know that the larvae can’t go around the filter,” Jarvi says. “We just don’t know.”
She thinks a larger study is needed to determine how catchment systems overall can be designed to better prevent rat lungworm. But that study would cost about $600,000.
Completing the “diagnostics expansion study”—which is developing the blood test that that diagnosed Kana Covington — would take another $150,000 to $200,000. To finish the vegetable wash study, Jarvi believes, would require another $60,000 or so. Another crucial study —a “bio-assay” to determine whether rat lungworm larvae are actually dead, and not simply paralyzed or dormant from a treatment — would require yet another $15,000.
Two Puna members of the County Council, Jennifer Ruggles and Eileen O’Hara, are working to come up with the $15,000 in county money for the “bio-assay,” at least. And on Friday, members of the Ways and Means Committee — now chaired by Sen. Donovan Dela Cruz — toured the lab.
Bill 272 could still be revived in the next legislative session.