Researchers have identified a previously unknown virus that could pave the way for important medical innovations against dangerous mosquito-borne pathogens.
In a paper published September 4 in the Proceedings of the National Academy, researchers at the University of Texas Medical Branch in Galveston (UTMBG) say they have discovered a virus that is closely related to dangerous mosquito-borne pathogens, but with one very important difference.
“This virus is unique — it is related to all of these mosquito-borne viruses that cause disease and cycle between mosquitoes and animals, and yet it is incapable of infecting vertebrate cells,” said Farooq Nasar, a UTMBG graduate student who led the study. “It’s a gift, really, because we can compare it to other alphaviruses and figure out the basis of their ability to infect a variety of animals, including humans.”
Alphaviruses are a genus of predominantly mosquito-borne pathogens that include chikungunya, Venezuelan equine encephalitis and eastern equine encephalitis.
The virus, known as Eilat, was discovered in a virus sample collected over 30 years ago by Joseph Peleg of Hebrew University.
Researchers saw that Peleg’s specimen killed insect cells but left animal cells untouched. The unusual behavior prompted them to send the sample to Columbia University to search for genetic material. The results of this process (known as “deep sequencing”) showed that there were actually two viruses in the sample – one that killed the insect cell, and another, Eilat, that left the cell unharmed.
“We were extraordinarily lucky to have that other virus in our sample, because without the cell death it caused, we never would have done the work that led us to Eilat,” Nasar said.
“Essentially, we found it by accident.”
According to researchers, the Eilat virus could help in the prevention and treatment of its more dangerous relatives.
By combining the Eilat virus with these more dangerous relatives, researchers can create viruses that replicate in insect cells and produce an immune response, yet remain totally harmless – thus making it possible to vaccinate animals and, perhaps one day, people.
The hybrid viruses could also mean safer conditions for humans and animals working with viruses like eastern equine encephalitis, and serve as a basis for new treatments and diagnostic tools in the case of an alphavirus outbreak.