Flu virus from bats might pose human threat
ATLANTA, GA - In recent years the influenza virus transmitted from sources such as bird and swine have attracted significant attention because of their ability to spread to humans and possibly cause pandemics. Now, another source of the flu virus has been discovered: bats. Researchers affiliated with the Centers for Disease Control and Prevention (CDC) that they have uncovered genetic fragments of a flu virus in bats. The results of their findings were published online in the journal Proceedings of the National Academy of Sciences.
Although bats have been suspected of being able to harbor the flu virus, this is the first report that furnishes proof. To date, the researchers have not been able to grow it in chicken eggs or cell cultures as they have with other viruses. The researchers noted that influenza A viruses, which are carried by animals, have caused global pandemics in humans.
However, it is currently unclear whether the newly-discovered virus will pose a threat to humans. They note that most influenza A viruses circulate in waterfowl; however, those that can infect mammals are thought to pose the greatest risk for not only spreading to humans but also and the generation of pandemic or panzootic viruses. (Panzootic viruses are those that can infect a wide variety of animals.)
In 2009 and 2010, the researchers collected more than 300 bats. While conducting research on rabies, which can be transmitted by bats, the researchers discovered the presence of an influenza A virus from yellow-shouldered bats captured at two locations in Guatemala. They noted that this new strain was different from other strains of influenza A viruses. They noted that the inability to grow the virus in cell cultures and chicken embryos suggests that it requires different requirements for growth than known influenza viruses. However, despite its divergence from known influenza A viruses, the bat virus appears to be capable of exchanging genetic material with human influenza viruses in human cells. As a result, it may be capable of intermingling genetically with human viruses. If so, it might be able to trigger a pandemic.
The researchers theorize that centuries ago some bats were stricken with a flu virus and the strain subsequently mutated to a new variety. Yellow-shouldered bats eat fruit and insects; however, they do not bite humans. However, it is possible that they could leave the virus on produce and a human could get infected by taking a bite. The researchers suspect that some individuals have been infected with the newly-discovered virus in the past. Now that they have identified it, they plan to search for it in other bat species as well as humans and animals.