H1N1 is spreading more widely than official figures indicate, with a footing established in at least three regions – North America, Asia and Europe.

One in 20 cases is being officially reported in the U.S., meaning more than 100,000 people have probably been infected nationwide with the new H1N1 flu strain, according to the Centers for Disease Control and Prevention. In the U.K., the virus may be 300 times more widespread than health authorities have said, the Independent on Sunday reported yesterday.

Japan, which has reported the most cases in Asia, began reopening schools over the weekend after health officials said serious medical complications had not emerged in those infected. The virus is now spreading in Australia.

Forty-six countries have confirmed 12,515 cases, including 91 deaths, according to the World Health Organization’s latest tally. Almost four of every five cases were in Mexico and the U.S., where the pig-derived strain was discovered last month. Most of those infected experience an illness similar to that of seasonal flu. The main difference is that the new H1N1 strain is persisting outside the Northern Hemisphere winter.

“While we are seeing activities decline in some areas, we should expect to see more cases, more hospitalizations and perhaps more deaths over the weeks ahead and possibly into the summer,” Anne Schuchat, CDC’s interim deputy director for science and public health program, reported on a May 22 conference call.

So is it a pandemic?

This outbreak has certainly met the WHO’s criteria for a pandemic – what is getting in the way of WHO raising the level is the politics.  Most countries and companies plans are based on the WHO levels.  WHO cites that moving the level to 6 could be damaging, as those plans will reach that critical trigger.  Is WHO assuming that those plans are on automatic pilot?  What happened to the use of good judgment on the part of these entities?

Rather than changing the definition it would be far more helpful if WHO helped everyone understand that our current is more like 1957 or 1968 rather than 1918.  And of course….it could change.