New Flu Virus Found in Guatemalan Fruit Bats, Not Believed to be a Threat to Humans

A new influenza A virus discovered in fruit bats in Guatemala does not appear to present a current threat to humans, but should be studied as a potential source for human influenza, according to scientists from the Centers for Disease Control and Prevention who worked with University of the Valley of Guatemala. The study was published today in the journal Proceedings of the National Academy of Sciences.

This is the first time an influenza virus has been identified in bats, but in its current form the virus is not a human health issue, says Dr. Suxiang Tong, team leader of the Pathogen Discovery Program in CDCs Division of Viral Diseases and lead author of the study.  The study is important because the research has identified a new animal species that may act as a source of flu viruses. 

For the bat influenza virus to infect humans, it would need to obtain some genetic properties of human influenza viruses. This can occur in nature through a process called reassortment. Reassortment occurs when two or more influenza viruses infect a single host cell, which allows the viruses to swap genetic information. Reassortment is a complicated chain of events that can sometimes lead to the emergence of new influenza viruses in humans. Preliminary CDC research on the new virus suggests that its genes are compatible with human influenza viruses.

Fortunately, initial laboratory testing suggests the new virus would need to undergo significant changes to become capable of infecting and spreading easily among humans, says Dr. Ruben Donis, chief of the Molecular Virology and Vaccines Branch in CDCs Influenza Division and a study co-author.  A different animal such as a pig, horse or dog would need to be capable of being infected with both this new bat influenza virus and human influenza viruses for reassortment to occur.

Bat influenza viruses are known only to infect little yellow-shouldered bats, which are common in Central and South America and are not native to the United States.  CDC works with global disease experts to monitor influenza viruses that circulate in animals, which could affect humans.  Previous pandemics of the 20th century, as well as the 2009 H1N1 pandemic, were caused by influenza viruses in animals that gained the ability to infect and spread easily in humans.