Question of priorities | 'Epicentre' commuters | Helen Rumbelow | Ben Macintyre | Dr Mark Porter | WHO updates | Swine flu: full coverage

Mexico's President has told citizens to stay at home for five days from tomorrow as the embattled country begins a partial shutdown of its economy.

The message came after the World Health Organisation raised its alert level and gave warning that a swine flu pandemic was imminent, while three more countries confirmed cases of the deadly virus.

Costa Rica, Switzerland and Peru bring to 12 the number of countries that have reported cases of the H1N1 strain, and Texas officials said that a 22-month-old boy had died while on a family visit from Mexico, the first confirmed swine flu death outside the country.

In his first televised address since the crisis erupted last week, President Felipe Calderón told Mexicans to stay at home with their families. The country will suspend non-essential work and services, including some government ministries, from May 1 to 5.

"There is no safer place than your own home to avoid being infected with the flu virus," President Calderón said.

Mexico reported another 17 deaths potentially linked to swine flu, bringing the total to as many as 176.

"Influenza pandemics must be taken seriously precisely because of their capacity to spread rapidly to every country in the world," Margaret Chan, director-general of the WHO, said yesterday, as she raised the official alert level to phase 5, the last step before a pandemic.

"The biggest question is this: how severe will the pandemic be, especially now at the start," Ms Chan said. But she added that the world "is better prepared for an influenza pandemic than at any time in history".

In Mexico City, a metropolis of 20 million, all schools, restaurants, nightclubs and public events have been shut down to try to stop the disease from spreading, bringing normal life to a virtual standstill.

Almost a week after the H1N1 swine flu virus first emerged in California and Texas and was found to have caused dozens of deaths in Mexico, Spain reported the first case in Europe of swine flu in a person who had not been to Mexico, illustrating the danger of person-to-person transmission.

Both US and European officials have said that they expect to see swine flu deaths.

President Obama said yesterday that there was no need for panic and rejected the possibility of closing the border with Mexico. "At this point [health officials] have not recommended a border closing," he said.

"From their perspective, it would be akin to closing the barn door after the horses are out, because we already have cases here in the United States."

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