Scientists find that ticks carry Heartland virus

Scientists found that a new virus that infected two men from northwestern Missouri in 2009 is being carried by ticks in the region, according to a study published on Monday.

Heartland virus, also known as HRTV, was discovered when a doctor treating the two infected men sent the blood samples to a U.S. Centers for Disease Control and Prevention laboratory in Atlanta for testing. Since the men reported being bitten by ticks, the scientists assumed the tests would reveal a common tick-borne disease, ehrlichoiosis. The tests instead revealed a virus that had never been recognized.

Researchers from the CDC and the Missouri Department of Health collected 56,428 ticks to test infection rates. The researchers found the virus infection rate in nymph stage tick from one farm owned by a patient was approximately one in five hundred ticks during the study period.

"Ten samples of ticks tested positive for the Heartland virus, nine of which were collected from the property of one of the patients and one that came from conservation lands nearby," Harry Savage, the lead author of the paper, said. "It's pretty strong evidence that the virus is persisting from season to season in tick populations and that these ticks play an important role in disease transmission."

While the ticks that carry the virus, known as lone star ticks, are common in many other parts of the country, there are no other reports of HRTV in any other tick populations aside from the ones isolated in northwestern Missouri.

"This research illustrates the ever-changing world we live in and why we must sustain our nation's investment in research into these types of diseases that the majority of Americans will never hear of," David Walker, the president of the American Society of Tropical Medicine and Hygiene, said. "It is only by getting trained experts into the field and doing the necessary work of collecting and testing thousands of specimens, as these scientists did, that we can be one step ahead of what could become another serious health threat carried by ticks."

Symptoms of HRTV include fever, headaches and low white blood cell and platelet counts. The CDC recommends that individuals avoid Heartland virus and other tick-borne viruses by wearing repellent, showering soon after being outdoors, checking for ticks daily and contacting a doctor in case of fever or rash.