A new study of the influenza virus shows the path the virus took to colonize humans is different than originally thought, according to research published in Nature.
Influenza infects many species, including birds, pigs and horses. The virus may mutate once it has colonized an original host, which may pose a danger to humans, depending on the mutation. To determine the path the flu virus has taken to infect humankind, scientists analyzed more than 80,000 genetically different influenza viruses, creating a genetic evolutionary tree.
In particular, scientists discovered that the avian flu, also known as the bird flu, is most likely a recent mutation of the influenza virus, originating around the 1870s, according to a news release. Previously, scientists had believed the virus was much older.
The horse flu pandemic of the 1870s in North America coincided with the beginning of reports of chickens being killed by what was then described as influenza. The period news reports were supported by genetic findings in the virus' family tree.
The finding also clarifies the origins of the influenza pandemic of 1918, showing the genome of the deadly virus passed directly from birds to humans, possibly specifically in North America. In addition, the tree suggests domestic birds, rather than wild birds, are the major reservoir of flu virus.
Since 2003, the H5N1 avian flu has caused 600 deaths after the virus, termed "highly pathogenic" for its ability to spread rapidly among birds, mutated on many occasions to a form able to colonize human hosts.
The H7N9 avian influenza virus has been particularly problematic in China in 2014, passing from domestic poultry to humans and possibly occasionally from human-to-human transmission, though rarely. As of Feb. 14, the strain has caused 205 infections and 26 deaths, according to the World Health Organization.
More Articles on Infection Control:
Kodak, PurThread Collaborate for Hard Surface Disinfection
Collaborative Pharmaceutical Care Decreases Medication Errors
Patient Safety Tool: Infection Prevention for Cancer Patients