# 3144
A terrific report this morning on NPR’s Morning Edition (with audio file) on the probable origins of the new H1N1 virus.
Richard Knox manages to cover a wide range of issues in his report, including what we are learning about the history of this virus, how viruses reassort in pigs, and our lack of knowledge over which genetic changes affect the virulence of an influenza virus.
The audio file and the written article cover the same ground, albeit with some differences. Well worth your time to review both.
Inside The New Flu Virus
by Richard Knox
Listen Now [4 min 23 sec]
The H1N1 swine flu virus in the influenza laboratory at the Centers for Disease Control and Prevention in Atlanta. Centers for Disease Control and Prevention
Morning Edition, May 7, 2009 · A crash effort to analyze the genes of the swine flu virus has revealed that it first emerged in humans last year — most likely last fall.
"The consistent range we're getting out is the second half of last year — between June and December," says Oliver Pybus of Oxford University. "The best estimate is the middle of that range, kind of September."
That means the newly recognized virus has been hiding in plain sight for the past eight months or so. Researchers say it probably had been circulating in Mexico and causing disease there, but its presence was masked by cases of regular flu and the absence of lab tests to identify the newcomer.
