Researchers have developed a new experimental drug in the fight against a virus that causes Argentine hemorrhagic fever. According to a report from UPI, scientists are calling the infection a “bioterror” threat that can lead to a number of bad health outcomes, including death.

Researchers say they have successfully tested the drug in guinea pigs, but it still isn’t ready for human trials. They’re rushing to produce a drug that can battle Argentine hemorrhagic fever, caused by the transmission of the Junin virus.

There is currently no medication for the fever – the best treatment doctors can give is a plasma transfusion from another person who has already survived a bout with the disease. The antibodies developed in survivors are the only known effective method of treating the virus.

The drug, produced by Mapp Biopharmaceutical in San Diego, would be in perilously short supply were an outbreak to arise. Dr. Larry Zeitlin, the president of Mapp Bio, is pushing for an increase in production to create a stockpile should the virus start to get out of hand.

Junin virus is currently confined to rural parts of Argentina, and is carried by a number of different species of rodents. Humans can contract the virus if they contact droppings, urine or saliva that has been contaminated. It’s rare for the virus to pass between people, but doctors say it is possible.

While roughly 10 to 50 people are infected by the virus each year, Dr. Delia Ernia, a scientist with Argentina’s National Laboratories and Health institutes Administration says the areas affected are expanding each year.

“As we’ve seen with the Ebola outbreak in West Africa and the ongoing Zika epidemic, it’s very difficult to predict when and where viruses like these will spread,” said Zeitlin. “Junin is not a virus I lose sleep over, but it’s one to keep a watchful eye on.”

More information from the CDC about viral hemmohagic fevers can be found here.