Monday, February 27, 2012

A New Flu Comes Up To Bat


UPDATED:  Helen Branswell has a report on this story HERE, and you’ll find another report by Virginia Gewin  on HERE.



Photo Credit- Wikipedia


# 6177


A fascinating story today coming from the journal PNAS, that is eerily reminiscent of fictional MEV-1 virus from the movie Contagion


Researchers report the discovery of never before seen influenza virus, that surprisingly, was detected in bats. Specifically, from little yellow-shouldered bats (Sturnira lilium) captured at two locations in Guatemala.


Scientists have previously identified 16 different hemagglutinin (HA) proteins, and 9 different neuraminidase proteins.


And while birds are the natural host for influenza viruses, they’ve never been isolated in bats before.


This new influenza is described as deviating from the 16 known HAs and is designated as H17. The neuraminidase (NA), and internal genes, are also highly divergent from previously known influenzas.


Despite all of these differences, the authors state this bat virus appears to be genetically compatible with human and avian influenza viruses, and the potential for reassortment exists.


Unfortunately, the entire report is behind a pay wall, but according to an AP report by Mike Stobbe, there remains some questions over exactly what these researchers have uncovered.


One scientist - Richard Fulton of Michigan State University - pointed out that the authors have not been able to grow the virus in cell cultures or egg embryos, and that they only have isolated fragments of the virus.


More research will be needed to determine what, if any, implications this new found pathogen will have to public health. Meanwhile, researchers are already looking for it, and similar viruses, in other hosts and bat colonies.



A distinct lineage of influenza A virus from bats

Suxiang Tong, Yan Li, Pierre Rivailler, Christina Conrardy, Danilo A. Alvarez Castillo, Li-Mei Chen,Sergio Recuenco, James A. Ellison, Charles T. Davis, Ian A. York, Amy S. Turmelle, David Moran, Shannon Rogers, Mang Shi, Ying Tao, Michael R. Weil, Kevin Tang, Lori A. Rowe, Scott Sammons, Xiyan Xu, Michael Frace, Kim A. Lindblade, Nancy J. Cox, Larry J. Anderson, Charles E. Rupprecht, and Ruben O. Donis


Influenza A virus reservoirs in animals have provided novel genetic elements leading to the emergence of global pandemics in humans. Most influenza A viruses circulate in waterfowl, but those that infect mammalian hosts are thought to pose the greatest risk for zoonotic spread to humans and the generation of pandemic or panzootic viruses.


We have identified an influenza A virus from little yellow-shouldered bats captured at two locations in Guatemala. It is significantly divergent from known influenza A viruses. The HA of the bat virus was estimated to have diverged at roughly the same time as the known subtypes of HA and was designated as H17. The neuraminidase (NA) gene is highly divergent from all known influenza NAs, and the internal genes from the bat virus diverged from those of known influenza A viruses before the estimated divergence of the known influenza A internal gene lineages.


Attempts to propagate this virus in cell cultures and chicken embryos were unsuccessful, suggesting distinct requirements compared with known influenza viruses. Despite its divergence from known influenza A viruses, the bat virus is compatible for genetic exchange with human influenza viruses in human cells, suggesting the potential capability for reassortment and contributions to new pandemic or panzootic influenza A viruses.