Margaret Chan, the director-general of the World Health Organization (WHO), has officially declared the first global influenza pandemic in 41 years, for the A(H1N1) virus. “The world is now at the start of the 2009 pandemic,” she said. That makes it the fourth flu pandemic in a century, after 1918, 1957 and 1968. “The scientific criteria for a pandemic have been met,” she said; on 11 June the WHO moved to the topmost of its pandemic threat scale, phase 6, which indicates sustained community-level outbreaks in two or more countries in one other WHO region beyond initial community spread in one WHO region. “Further spread is considered inevitable,” she said.
“The declaration of a pandemic does not suggest there is a change in the behaviour of the virus, just that it is spreading in more parts of the world,” added Thomas Frieden, director of the US Centers for Disease Control and Prevention in Atlanta, Georgia. “It does send a strong message that the virus is here, in all likelihood here to stay.”
The virus has spread to 74 countries, with evidence of community spread in Australia, the United Kingdom and Chile, among others. More than 28,700 cases have been confirmed by lab tests worldwide — likely only a fraction of the total number — with 144 deaths documented.
