by Greg Contreras
In a discussion this morning with a cell biologist and medical doctor working at Johns Hopkins, my friend thought this 4-part flu combination is highly unusual and looks like it could be man-made.
Especially because it has an avian strain. My doctor friend (he’s Taiwanese) explained that in Asia, it’s common for a avian-swine-human flu to happen naturally, but this virus first showed up in Mexico, where pigs and ducks are not usually raised together.
From CDC via Wikipedia:
Anne Schuchat, director of CDC’s National Center for Immunization and Respiratory Diseases, said that the American cases were found to be made up of genetic elements from four different flu viruses — North American swine influenza, North American avian influenza, human influenza A virus subtype H1N1, and swine influenza virus typically found in Asia and Europe.
For two cases a complete genome sequence had been obtained. She said that the virus was resistant to amantadine and rimantadine, but susceptible to oseltamivir (Tamiflu) and zanamivir (Relenza).
Preliminary genetic characterization found that the hemagglutinin (HA) gene was similar to that of swine flu viruses present in U.S. pigs since 1999, but the neuraminidase (NA) and matrix protein (M) genes resembled versions present in European swine flu isolates. Viruses with this genetic makeup had not previously been found to be circulating in humans or pigs, but there is no formal national surveillance system to determine what viruses are circulating in pigs in the U.S. The seasonal influenza strain H1N1 vaccine is thought to be unlikely to provide protection.