Scientists say severe H1N1 outbreak might not occur

Kathleen Blanchard's picture
Flu researcher

Two scientists from the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, says a severe H1N1 outbreak is in not guaranteed. A commentary in the Aug. 12 issue of the Journal of the American Medical Association from David M. Morens, M.D., and Jeffery K. Taubenberger, M.D., Ph.D says an analysis of 14 global or regional influenza epidemics during the past 500 years show no pattern that can predict an upcoming severe outbreak of H1N1 influenza.

The researchers noted that flu outbreaks that occurred in 1957 and 1968 did not recur more than one season, and the outbreaks never became more severe. They say that viruses are unpredictable and follow no pattern. H1N1 flu may not increase in severity, given the possibility of pre-existing immunity and its only modest ability to spread.


The idea that H1N1 flu will increase in severity comes from speculation about the 1918 flu pandemic that may have been mild, and then became devastating. The scientists say there is a widely held belief that viruses follow such a pattern, but their analysis say it is not necessary so.

The two physicians do not suggest we let down our guard – however there is no guarantee that scrambling for protection against H1N1 flu by way of vaccines and other methods is absolutely necessary. Their analysis provides some hope that H1N1 influenza will not take a major toll, nor might it claim as many lives as past flu pandemics.

The authors say "influenza epidemics are lived forward and understood backward”. Close tracking of H1N1 influenza is still needed. However, there is no guarantee that a severe outbreak of H1N1 influenza will occur.

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