Heartland Virus

Several deadly tick-borne viruses have emerged in the Midwest in recent years, including the Heartland virus, first discovered in Missouri. Scientists say there are likely more that have gone undiagnosed.

So far, two Missouri farmers are the only known cases of the tick-borne virus in the world. But experts are sure they'll find more. The men recovered but suffered serious illness that required hospital care and weeks of convalescence.