Health officials in the United States have come up with a system for dealing with a flu pandemic.
The plan is an early-warning ranking system similar to that deployed at times of hurricanes and is intended to protect and mobilize the country against a flu pandemic.
The system advocates a community-based response which would categorize flu pandemics on a scale of 1 to 5, with 5 being the deadliest.
The "Pandemic Severity Index" (PSI) sets out levels of recommendations, ranging from hand washing to closing schools, which are intended to slow the spread of the virus while a vaccine is being prepared.
The new PSI suggests gradually escalating the strategies when a super-flu's threat becomes great enough to justify doing so.
According to Dr. Julie Gerberding, director of the U.S. Centers for Disease Control and Prevention (CDC), not all pandemics are equally severe and information they now have on epidemiology will help to devise a severity index.
The CDC has quite deliberately copied the nation's hurricane ranking system to help the general public immediately recognize what to expect once a pandemic strikes, and help communities decide what measures to take.
Dr. Julie Gerberding says a pandemic which does not quickly from person to person would be considered a fairly mild pandemic, while one such as the 1918 outbreak moved with extraordinary speed and had an unusually high mortality rate; that would be categorized as a category 5 pandemic.
The CDC has conducted it's first "fully functional" avian flu exercise, in which all personnel at the Atlanta headquarters were involved.
Experts have been concerned for some time that the bird flu virus currently circulating around the globe could mutate into a new type of flu virus for which people have little immunity, triggering a pandemic with the potential to kill millions worldwide.
The current form of H5N1 bird flu doing the rounds is a worry because of its virulence and the ease of transmission among flocks of domestic birds.
According to the World Health Organisation (WHO) bird flu has to date infected 270 people around the world and killed 165, mostly in Asia.
So far, the H5N1 virus does not appear to have developed the ability to jump easily from person to person.
But despite recent reports that a pandemic may not be close-at-hand, U.S. health officials are still concerned.