GENEVA — The World Health Organization declared a swine flu pandemic Thursday — the first global flu epidemic in 41 years — as infections in the United States, Europe, Australia, South America and elsewhere climbed to nearly 30,000 cases.
The long-awaited pandemic announcement is scientific confirmation that a new flu virus has emerged and is quickly circling the globe. WHO will now ask drugmakers to speed up production of a swine flu vaccine. The declaration could also prompt governments to devote more money toward efforts to contain the virus.
WHO chief Margaret Chan made the announcement Thursday after the U.N. agency held an emergency meeting with flu experts. Chan said she was moving the world to phase 6 — the agency's highest alert level — which means a pandemic, or global epidemic, is under way.
"The world is moving into the early days of its first influenza pandemic in the 21st century," Chan told reporters. "The (swine flu) virus is now unstoppable."
On Thursday, WHO said 74 countries had reported 28,774 cases of swine flu, including 144 deaths. Chan described the virus as "moderate." According to WHO's pandemic criteria, a global outbreak has begun when a new flu virus begins spreading in two world regions.
The agency has stressed that most cases are mild and require no treatment, but the fear is that a rash of new infections could overwhelm hospitals and health authorities, especially in poorer countries.
Still, about half of the people who have died from swine flu were previously young and healthy — people who are not usually susceptible to flu. Swine flu is also crowding out regular flu viruses. Both features are typical of pandemic flu viruses.
The last pandemic — the Hong Kong flu of 1968 — killed about 1 million people. Ordinary flu kills about 250,000 to 500,000 people each year.
Swine flu is also continuing to spread during the start of summer in the northern hemisphere. Normally, flu viruses disappear with warm weather, but swine flu is proving to be resilient.
The decision might have been made much earlier if WHO had more accurate information about swine flu's rising sweep through Europe. Chan said she called the emergency meeting with flu experts after concerns were raised that some countries like Britain were not accurately reporting their cases.
After Thursday's meeting, Chan said the experts agreed there was wider spread of swine flu than what was being reported.
Chan would not say which country tipped the world into the pandemic, but said all countries and experts agreed that it was time to declare a global outbreak.
WHO said it is now recommending that flu vaccine makers start making swine flu vaccine. Drug giant GlaxoSmithKline PLC said it could start large-scale production of pandemic vaccine in July, but that it would take several months before large quantities would be available.
Many health experts say WHO's pandemic declaration could have come weeks earlier, but the agency became bogged down by politics. In May, several countries urged WHO not to declare a pandemic, fearing it would cause social and economic turmoil.
"This is WHO finally catching up with the facts," said Michael Osterholm, a flu expert at the University of Minnesota who has advised the U.S. government on pandemic preparations.
Despite WHO's hopes, Thursday's announcement will almost certainly spark panic about the spread of swine flu in some countries.
Fear has already gripped Argentina, where thousands of people worried about swine flu flooded into hospitals this week, bringing emergency health services in the capital of Buenos Aires to the brink of collapse. Last month, a bus arriving in Argentina from Chile was stoned by people who thought a passenger on it had swine flu.
Chile has the most swine flu cases in South America, and the southern hemisphere is moving into its winter flu season.
In Hong Kong on Thursday, the government ordered all kindergartens and primary schools closed for two weeks after a dozen students tested positive for swine flu — a move that some experts would consider an overreaction. The decision affected more than half a million students.
In the United States, where there have been more than 13,000 cases and at least 27 deaths from swine flu, officials at the U.S. Centers for Disease Control and Prevention said the move would not change how the U.S. tackled swine flu.
"Our actions in the past month have been as if there was a pandemic in this country," Glen Nowak, a CDC spokesman, said Thursday.
The U.S. government has already taken steps like increasing availability of flu-fighting medicines and authorizing $1 billion for the development of a new vaccine against the novel virus. In addition, new cases seem to be declining in many parts of the country, U.S. health officials say, as North America moves out of its traditional winter flu season.
Still, New York City reported three more swine flu deaths Thursday, including one child under 2.
In Mexico, where the epidemic was first detected, the outbreak peaked in April. Mexico now has less than 30 cases reported a day, down from an average of 300, Health Secretary Jose Angel Cordova said. Mexico has confirmed 6,337 cases, including 108 deaths.
Cordova said he is concerned that other countries are not taking drastic measures to stop its spread like Mexico, which closed schools, restaurants and theaters, and canceled public events after the government detected the epidemic in late April.
Many experts said the declaration of a pandemic did not mean the virus was getting deadlier.
"People might imagine a virus is now going to rush in and kill everyone," said John Oxford, a professor of virology at St. Bart's and Royal London Hospital. "That's not going to happen."
But Oxford said the swine flu virus might evolve into a more dangerous strain in the future. "That is always a possibility with influenza viruses," he said. "We have to watch very carefully to see what this virus does."