Scientists recently discovered a new virus that can be transmitted through blood transfusions, but the jury is still out on how dangerous it is. So far, the researchers claim the virus resembles both hepatitis C, a serious infection that can cause permanent liver damage, and pegivirus, which is often harmless in humans. Their findings are recorded in the journal mBio.

Researchers say that the new virus, which they are calling hepegivirus-1, or HHpgV-1, should not cause alarm yet.

“It’s the first transfusion-associated virus that’s been described in a long time,” Dr. Ian Lpikin, infectious disease expert and co-author of the study, told NBC News. “We don’t know if it is going to be a significant cause of human hepatitis.”

But it doesn’t seem to be that way. “So far there is no need to be concerned,” said Amit Kapoor, assistant professor at Columbia University and lead author of the study. “We don’t really know if there is ongoing transmission of this virus. It may be good for you.”

Similarly, Lipkin noted that this new virus should not be taken as something akin to SARS, MERS, or HIV, but greater investigation into the nature of the virus must still be done.

For the research team, discovering the virus took sampling from blood decades past, which was preserved at the National Institute of Health’s blood bank. The samples came from 46 participants between the years 1974 and 1980, two of which contained the virus. But, upon reviewing the two patients’ medical histories, both seemed to have “cleared” the virus, and didn’t have any resulting symptoms.

All of the 46 participants in the study had received blood transfusions to treat hemophilia. Researchers observed that those who contracted the virus seemed to get it after the transfusion.

To compare the results from this study, researchers cross referenced it with another study looking at 106 people who received transfusions during the same time period. Out of the total sample, two contracted the virus, and one of them seemed to have it in their system for as long as five years. Both eventually cleared the virus, too.

“We just don’t know how many viruses are transmitted through the blood supply,” said Kapoor. “There are so many viruses out there, and they need to be characterized in order to ensure that transfusions are safe.”

Though hemophilia used to commonly be treated with human blood products, more recent methods involve genetically engineered products to steer clear of potentially unidentified viruses. But, blood transfusions are still a frequent occurrence in U.S. hospitals. As a result, the researchers suggest we make a vigilant effort to identify any possible viruses transmitted through blood that could be dangerous to human health.

“More than 30 million blood components are transfused annually in the United States alone,” researchers wrote. “Surveillance for infectious agents in the blood supply is key to ensuring the safety of this critical resource for medicine and public health.”

Source: Kapoor A, Kumar A, Simmonds P, et al. Virome Analysis of Transfusion Recipients Reveals a Novel Human Virus That Shares Genomic Features with Hepaciviruses and Pegiviruses.