(INDYSTAR.com) - The Centers for Disease Control and Prevention has confirmed that two southern Indiana residents have fallen ill over the past two years after contracting a newly discovered tick-borne virus, state health officials announced Tuesday.

Both individuals survived the infection of the Heartland virus, which first sickened two people in Missouri in 2009. By 2014 six additional cases had been found in Missouri and Tennessee.

Oklahoma and Arkansas have also seen cases of the virus, according to the Indiana State Department of Health.

Most people who fall ill require hospitalization. At least two people have died, according to federal health officials. People who fall ill usually do so between May and September.

The virus, thought to be transmitted to humans by ticks, causes fever, flu-like symptoms and a drop in the blood cells that fight infection and help with blood clotting. It can also cause diarrhea, loss of appetite and nausea.

Scientists think that the Lone Star Tick, which also carries the bacteria that cause ehrlichiosis, a bacterial illness, is the only tick species that carries this virus. Scientists have found the virus in animal species in 13 states.

State health officials caution Indiana residents to take precaution against ticks, which can carry a variety of diseases and check carefully for their presence whenever they have been outside. In 2016, the state saw more than 200 cases of tick-borne illness.

Call IndyStar staff reporter Shari Rudavsky at (317) 444-6354. Follow her on Twitter and on Facebook.