No possibly related systemic AE was experienced by volunteers from the IRIV group and less flu-like symptoms were reported in the IRIV group when compared to the verum groups.
While acknowledging responsibility for the mix-up, health care company Baxter says it will not reveal the exact chain of events that led the unsuspecting labs to receive H5N1, the highly lethal avian influenza virus, in samples of less dangerous flu strains.
Less often, flu is spread by touching a contaminated surface, then touching one's eyes, nose or mouth.
The less bird flu is present in nature and domestically on farms, the less likely it is for such an evolution to occur, they say.
But public health officials say there appears to be a pattern of areas that had big outbreaks in the spring, like New York, Boston and Philadelphia, seeing less swine flu now.
Vaccine manufacturers commonly use a virus constructed from the backbone of a less infectious flu strain together with the hemagglutinin and neuraminidase genes of the strain they want to make a vaccine against.
Center Evan Eschmeyer came down with the flu less than 48 hours after he received a flu shot.
With the exception of Meridian, these companies are much larger than Quidel and less dependent on flu tests.
A new study suggests that overweight people benefit less from the flu vaccine than those of normal weight, and the heavier they are, the lower their immune response to the shot over time.
Scientists from the National Institute for Infectious Diseases in Tokyo looked at 43 laboratory-confirmed cases from Kobe and reported this week that those who had been vaccinated did not seem to get swine flu less often than other patients.
Mr. Hagemeijer said the strength of the virus among wild birds possibly weakened as the southward migration season progressed, a trait he said was common in less dangerous bird flu viruses.
