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Investigators studied how easily the 2009 H1N1 influenza virus spread and how severely ill it made a community of ferrets, which are known to be a good model for estimating how influenza disease spreads in humans. Their findings are in agreement with observations of human infections, which indicate that the 2009 H1N1 viruses cause generally mild disease but also spread between individuals relatively effectively.
In this study, a swine-origin 2009 A/H1N1 virus isolated in the Netherlands was introduced to the ferrets. Researchers compared the effects of this virus to a strain of seasonal influenza and found that the 2009 H1N1 virus was more pathogenic, meaning that it replicated and spread throughout the respiratory tract more efficiently than the seasonal flu. In addition, the scientists found that virus shedding, or the expelling of the virus from the body, was more abundant in the upper respiratory tract of the 2009 H1N1-infected ferrets than those with seasonal flu. Subsequently, the 2009 H1N1 strain was also found to spread efficiently between ferrets through aerosol or respiratory droplets. Despite these characteristics, the 2009 H1N1 virus did not cause any mortality in the ferret model, whereas highly pathogenic influenza viruses (like avian H5 and H7 subtypes and the 1918 Spanish influenza virus) often prove fatal for ferrets.
VJ Munster et al. Pathogenesis and transmission of swine-origin 2009 A/H1N1 influenza virus in ferrets. Science. 325: 481-483. DOI: 10.1126/science.1177127 (2009).
Last Updated March 06, 2013
Last Reviewed March 06, 2013