But until now, there hasn't been a way to test humans for the Keystone virus, which is carried by the Aedes atlanticus mosquito, a cousin to the Zika-spreading Aedes aegypti.
A 16-year-old boy from north central Florida has made history in the least glamorous way - he has become the first documented case of a human Keystone virus infection.
"By finding the virus in a person, this tells us that the virus can infect humans, and that perhaps the former studies that indicated up to 20 percent of Florida residents of the Tampa area have been exposed to this virus (and not another closely-related one) are correct", John Lednicky, a research professor in the University of Florida's College of Public Health and Health Professions and lead author of the study, told Newsweek. Surveys conducted nearly 50 years ago found antibodies to the virus in about 20% of people in the Southeast, indicating that they'd been exposed, though live virus had never been found in a person before.
There is now no straightforward test to identify the Keystone virus, but Dr. Glenn Morris, director of the University of Florida's Emerging Pathogens Institute, said several biomedical companies have reached out about developing one.
"These viruses are known to cause encephalitis [inflammation of the brain] in several species, including humans", he noted. Two relatives of the Keystone virus, the Jamestown Canyon virus and La Crosse encephalitis virus, can cause inflammation of the brain, called encephalitis. "Additional research into the spread of vector-borne diseases will help us shine a light on the pathogens that are of greatest concern to both human and animal health". But it took a year and a half of laboratory work to determine that Keystone virus was present. Since then, it "has been found in animal populations along coastal regions stretching from Texas to the Chesapeake Bay", according to a statement from University of Florida Health. Morris believes that this virus has already infected many people in that region.
A mosquito-borne illness that could seriously affect the brain and was previously thought to be transmitted only to animals has been found in a human for the first time, Fox 13 News reported. They discovered that the patient contracted the Keystone virus after conducting viral cultures.
The unidentified boy, who had attended a band camp in Florida last summer, contracted an infection at the time and suffered with fever and severe rash.
The recent case was found during a screening campaign for Zika virus in Florida in 2016.
Morris said, "We couldn't identify what was going on".