Study revives bird origin for 1918 flu pandemicBreaking News
tags: Spanish flu, 1918
The virus that caused the 1918 influenza pandemic probably sprang from North American domestic and wild birds, not from the mixing of human and swine viruses. A study published today in Nature1 reconstructs the origins of influenza A virus and traces its evolution and flow through different animal hosts over two centuries.
“The methods we’ve been using for years and years, and which are crucial to figuring out the origins of gene sequences and the timing of those events, are all flawed,” says lead author Michael Worobey, an ecologist and evolutionary biologist at the University of Arizona in Tucson.
Worobey and his colleagues analysed more than 80,000 gene sequences from flu viruses isolated from humans, birds, horses, pigs and bats using a model they developed to map evolutionary relationships between viruses from different host species. The branched tree that resulted showed that the genes of the deadly 1918 pandemic virus are of avian origin....