Friday, August 14, 2009

It's not the flu that kills - it is the secondary infection (MRSA?)

Why does this matter? Because in 1918, many of the deaths were not directly due to the influenza virus. Instead, they were caused by ’secondary’ bacterial infections that ordinarily wouldn’t have killed people:

Their findings are striking in the context of modern conceptions of the 1918 pandemic; the great majority of deaths could be attributed to secondary bacterial pneumonia caused by common respiratory pathogens, particularly pneumococci, group A streptococci, and staphylococci, and not to the virus itself. In fact, although evidence of severe viral bronchiolitis was found, often the primary viral insult appeared to be resolving at the time of the secondary infection responsible for the fatality. Their conclusions are strengthened by the remarkable consistency in theme, if not details, displayed across the many studies reviewed and the inclusion in their review of not only gross pathologic findings but blood and lung tissue culture data. In only 4% of the more than 8000 cases reviewed was no bacterial superinfection documented.

The article also reports that K. pneumoniae was implicated in the deaths of these patients (although it was less frequent than the Gram-positives), along with other Gram-negatives, such as E. coli. And if we can’t treat these patients due to antibiotic resistance, the number of deaths which are kicked started by influenza, but utlimately due to bacterial infection, will be higher than anyone is currently thinking about.

Complete article: It’s not the Flu that kills you, it’s the secondary infection (MRSA?)