JOPLIN, Mo. —
Kevin Badgley said that in the spring he can sometimes see tick nymphs “questing.”
They climb to the tops of plants, weeds or blades of grass, attach their back legs to the plant, and reach out and flail their front legs, waiting to attach to any animal that passes by.
Sometimes, said Badgley, a naturalist and education outreach specialist with the Missouri Department of Conservation, the young ticks seem to line up.
When that animal is a biped that lives in Missouri, the eagerness that ticks demonstrate to attach to some host can become a problem.
That ticks cause illnesses — Rocky Mountain spotted fever, tularemia, Q fever and Lyme disease — isn’t new, but what is new is being called the Heartland virus.
Two farmers in the St. Joseph area in 2009 were treated at Heartland Regional Medical Center there for fever and fatigue. Doctors initially suspected ehrlichiosis, a tick-borne illness common in Missouri, but the patients didn’t respond to antibiotics used to treat the disease. Doctors sent blood samples to experts at the Centers for Disease Control and Prevention.
CDC scientists then traveled to northwest Missouri, finding the new virus in ticks collected on the patients’ farms and in the Honey Creek Conservation Area. What has been dubbed the Heartland virus was detailed recently in a paper published in the American Journal of Tropical Medicine and Hygiene.
The author of the study, CDC research entomologist Harry Savage, was back in Andrew County near St. Joseph last week in the field, collecting more ticks.
Savage said by telephone that at this point, only the two human cases have been documented, but he’s sure there are others.
“Other Heartland cases out there probably have been misdiagnosed,” he said.
Savage said the lone star tick carries the virus. The female adult has a white spot.
The virus causes a fever, chills, body aches, nausea and diarrhea. The symptoms are similar to those associated with other tick-borne illnesses.
“This is just one more disease,” Savage said. “All we know now is it’s in northwest Missouri. There’s no reason to believe it’s not more widespread. Surveillance will be broadened to detect more human cases.”