The World Health Organization says flu viruses are unpredictable and constantly changing.  It says countries must not let down their guard, but must remain vigilant in monitoring the evolution of the Influenza A, H1N1 virus, which is being called Swine Flu.  The number of cases officially reported to WHO from 20 countries stands at 1025 confirmed cases, including 26 deaths.  

The World Health Organization says people should not focus too much on the figures, as they are fluid and change with great frequency.  It says the influenza A H1N1 virus is continuing to evolve and no one yet knows whether it will be a mild or serious outbreak.  

Assistant Director-General for Health Security and Environment, Keiji Fukuda, says the largest number of cases continue to be reported from Mexico, the United States and Canada, although infections are reported in Asia, Europe and Latin America.

He says WHO is maintaining its international influenza pandemic alert at phase five.   He says there has to be evidence of sustained community transmission of the virus in a country in a region outside North America for phase six to kick in.  

He says phase six has nothing to do with the severity of the disease.

"Phase six means that we are seeing continued spread of the virus to countries outside of one region," said Keiji Fukuda. "And, if we are seeing community outbreaks occur in multiple places of the world, it really tells us that the virus has established itself and that we can expect to see disease in most countries in the world.  So, that is different than the severity of a pandemic.  The severity of a pandemic has to do with when people get infected, how often are they going to develop really severe disease."  

Dr. Fukuda says it is very important to closely monitor the evolution of the disease.  He says the world is much better prepared to respond to a potential pandemic than it was in 1918.    

The so-called Spanish flu, which circulated around the world in 1918 and 1919 killed an estimated 50 million people.  WHO says there is no indication right now that the world is facing a situation like that, which occurred in 1918.

In a related issue, Dr. Fukuda reiterates WHO's position that people are getting infected with the H1N1 virus from other people and not from pigs.  He says people will not get infected from eating pork and pork products.  And, when handled correctly and cooked properly, they pose no problems.  

He says pigs are not a danger to people.  It is people who are a danger to other people.