A surge in cases of H1N1 swine flu in Australia may tip the balance and cause the World Health Organization to soon declare the first flu pandemic since 1968, agency officials said Tuesday.

Cases in Australia rose by more than 1,000 on Monday, with most occurring in the southern state of Victoria. Rapid spread of the virus in a region beyond North America has been considered a key factor in labeling the outbreak a pandemic.

"We are getting really very close to knowing that we are in a pandemic situation," WHO influenza chief Keiji Fukuda said in Geneva.

He said the agency was conce

The World Health Organization is holding off on declaring a flu pandemic while it prepares governments and the public for the announcement, said Keiji Fukuda, the agency’s assistant director-general of health security and environment.
The Geneva-based United Nations health agency wants to educate countries further about the meaning of a pandemic to prevent overreaction, Fukuda said on a conference call with journalists today. Raising the WHO’s six-step pandemic scale to its highest level might cause people who are healthy to flock to hospitals, preventing the sick from getting care, he said.
“We are really working pretty hard to get these messages out to people,” said Fukuda. “We know that we are getting closer probably to a pandemic situation.”

In the U.K., according to virologist professor John Oxford, the virus may be 300 times more widespread than health authorities have said...

...Oxford's estimate comes as leading scientists are warning that estimates by the U.K. and other governments on the spread of the disease are "meaningless" and hiding its true extent.

This led other experts to become concerned that the new virus strain could mutate over the coming months. Guan Yi, a leading virologist from the University of Hong Kong, for instance, described the new H1N1 influenza virus as "very unstable", meaning it could mix and swap genetic material when exposed to other viruses. During an interview he said "Both H1N1 and H5N1 are unstable so the chances of them exchanging genetic material are higher, whereas a stable (seasonal flu) virus is less likely to take on genetic material." The H5N1 virus is mostly limited to birds, but in rare cases when it infects humans it has a mortality rate of between 60% to 70%.[128] Experts worry about the emergence of a hybrid of the more virulent Asian-lineage HPAI (highly pathogenic avian influenza) A/H5N1 strain (media labeled "bird flu") with more human-transmissible Influenza A strains such as this novel 2009 swine-origin A/H1N1 strain (media labeled "swine flu"), especially since the H5N1 strain is and has been for years endemic in a variety of wild bird species in countries like China, Indonesia, Vietnam and Egypt.[128]