The Hawaii Department of Health has confirmed the third case of rat lungworm disease contracted in 2019 on Hawaii Island.

The individual who tested positive for rat lungworm is a resident of East Hawaii, according to a press release from DOH on Thursday.

Lab testing by DOH confirmed the infection in mid-April, although the person may have been infected as early as February.  The individual was hospitalized, and the exact source of infection could not be identified, DOH said

“Diagnosis and treatment of this disease is incredibly difficult, especially since there is still much we don’t know about the parasite and the disease,” said Health Director Bruce Anderson in the press release.

“The Governor’s Joint Task Force on Rat Lungworm Disease has done extensive work to develop preliminary clinical guidance for local physicians who may encounter patients with the disease and physician trainings will continue this year. That work, along with immediate reporting by physicians is critical to facilitate prompt, accurate diagnosis and appropriate patient management.”

Rat lungworm disease is caused by a parasitic worm called Angiostrongylus cantonensis, which reproduces itself in the lungs of rats. The larvae is released in rat feces, gets passed on to carriers such as slugs and snails, as well as freshwater shrimp, land crabs and frogs. Humans, in turn, can contract the disease by eating contaminated produce — or ingesting the carriers themselves.

The disease attacks the brain and the spinal cord, causing eosinophilic meningitis and often leaving the victims with long-lasting effects

DOH reported that there were a total of 9 laboratory-confirmed cases in Hawaii in 2018 and 19 laboratory-confirmed cases in 2017.