The heartland virus was discovered in 2009, when two men were hospitalized in Missouri. The men suffered from fever, diarrhea, low blood cell counts, muscle aches and other symptoms consistent with tick borne diseases. It was discovered upon further research that the men were infected with a previously unknown virus, which was named “heartland virus” and traced back to lone star ticks.
Since its discovery, over 50 cases of the heartland virus have shown up in people in 11 states in the south and midwestern US. Some of these cases were bad enough to require hospitalization. It is believed that the actual cases of the disease may be higher, as the condition is relatively unknown and tests for the disease are rare. A postmortem test even confirmed that someone in Georgia died of the disease in 2005. Furthermore, research shows that deer in the area have been exposed since at least 2001.
“Heartland is an emerging infectious disease that is not well understood,” said study senior author Gonzalo Vazquez-Prokopec, an associate professor at Emory University. “We’re trying to get ahead of this virus by learning everything that we can about it before it potentially becomes a bigger problem.”
Dr. Yomila Romer, formerly a part of the Vazquez-Prokopec lab, led research to look into the connections between the lone star tick and heartland virus. The researchers collected specimens of the lone star tick, both as an adult and as a nymph in different locations and times. Genetic analysis was carried out to detect the heartland virus. Three samples found the virus and the genetics between the samples were very similar. The samples showed very different genetics from the heartland virus outside of state.
“These results suggest that the virus may be evolving very rapidly in different geographic locations, or that it may be circulating primarily in isolated areas and not dispersing quickly between those areas,” explained Vazquez-Prokopec.
Further sample collecting in Georgia suggests that only one in every 2,000 ticks carries the heartland virus. The team plans on carrying out more research on ticks and tick borne illness in the future as diseases and tick health may change with climate change and growth of human populations.
“We will be gathering data to help support tick surveillance efforts by public health officials in Georgia,” Vazquez-Prokopec says. “Tick-borne diseases are a real and growing threat and the best way to deal with them is not to panic, but to do the science needed to learn everything we can about them.”
The journal is published in the journal Emerging Infectious Diseases.