Despite what appear to be community-level outbreaks of H1N1 in Japan, the WHO has not confirmed a full Phase 6 pandemic.
According to an Associated Press report at roughly 11:15 eastern, “WHO chief Dr. Margaret Chan says the swine flu epidemic is in ‘a grace period’ with the WHO alert remaining at phase 5 out of a possible six for the last month. She told the WHO annual assembly on Monday that no one can say how long this period will last. Chan says the danger now is that the swine flu virus could mix with other flu strains and become more dangerous.”
Phase 6 differs from Phase 5 in terms of how the disease is spreading and its geographic reach. The WHO pandemic alert system does not attempt to communicate the virulence of the contagion. There is, however, a push for a new approach that would begin to reflect comparative impact. Some speculate that reluctance to declare Phase 6 may reflect official concern for how the public could interpret such a move.
According to Bloomberg, the number of laboratory-confirmed cases of H1N1 in Japan is growing rapidly. Most of the new cases in Japan involve teenagers. As has been reported in other nations, the vast majority of individual cases in Japan are presenting with mild symptoms. The May 18 update WHO H1N1 update is available at: http://www.who.int/csr/don/2009_05_18/en/index.html
There is a growing body of evidence that young people are most susceptible to the new influenza strain. The New York Times reports, “This year’s swine flu is concentrated in those ages 5 to 24… and school outbreaks like those under way in New York and Houston are the norm.” Sunday’s Washington Post headlined, “Age of flu victims has big implications.”
While the New York Times report (above) suggests there is probably wide-spread under-reporting in the US figures, the CDC has confirmed over 4700 cases and five deaths in 47 states. A sixth death, a New York teacher, was reported on Sunday. But some are suggesting H1N1 may have played an indirect role in this death.
Today the WHO begins it annual meeting in Geneva. The AFP reports that, “The WHO is still considering whether to halt seasonal flu output in order to free up production capacity for large scale pandemic vaccine production.”
The online American Medical Association Journal, Disaster Medicine and Public Health Preparedness has published open access to a collection of H1N1 related articles.