WHO declares swine flu pandemic over

Margaret Chan, director general for the World Health Organization, announced August 10 that the swine flu pandemic was officially at an end.

“The world is no longer in phase 6 of influenza pandemic alert,” Chan said during a teleconference. “We are now moving into the post-pandemic period. The new H1N1 virus has largely run its course.”

Chan said the Emergency Committee, which had convened earlier that day, based its decision to declare an official end to the pandemic on the global situation, as well as reports from several countries that are now experiencing influenza.

A word of warning was issued by Chan, however, noting that just because we have entered the post-pandemic period, it does not mean the H1N1 virus has gone away. Based on experience with past pandemics, Chan said, health officials expect the H1N1 virus to take on the behavior of a seasonal influenza virus that could possibly continue to circulate for years to come.

“In the post-pandemic period, localized outbreaks of different magnitude may show significant levels of H1N1 transmission,” Chan said. “This is the situation we are observing right now in New Zealand, and may see elsewhere. In fact, the actions of health authorities in New Zealand, and also in India, in terms of vigilance, quick detection and treatment, and recommended vaccination, provide a model of how other countries may need to respond in the immediate post-pandemic period.”

Chan also noted that, based on experience with past pandemics, it is likely that the virus will continue to cause serious disease in younger age groups during the immediate post-pandemic period. Groups identified during the pandemic as at higher risk may remain at heightened risk. Chan said hopefully the number of such cases will diminish.

“Pandemics, like the viruses that cause them, are unpredictable,” Chan said. “So is the immediate post-pandemic period. There will be many questions, and we will have clear answers for only some. Continued vigilance is extremely important, and WHO has issued advice on recommended surveillance, vaccination, and clinical management during the post-pandemic period.”