Wellington  - Nearly 70 New Zealanders may have contracted swine flu following recent visits to Mexico or the United States, health officials announced Tuesday.

Another 56 people who had developed flu-like symptoms were being tested to see if they had the influenza A strain, which has been linked with the outbreak of swine flu, H1N1, that the World Health Organization said was evolving rapidly.

Mexico City  - Mexico on Monday closed schools and universities until May 6 and limited commercial activity in the capital to stop the spread of swine flu.

Mexico is believed to be the epicentre of the swine flu outbreak. An estimated 149 people have died from influenza, but only 26 deaths have so far been linked to the swine flu virus.

The US Centres for Disease Control and Prevention and the State Department issued an advisory late Monday urging against non- essential travel to Mexico, in effect through July.

Mexico City  - The bells of Mexico City's cathedral rang in prayer, and the figure of Our Father Jesus of Health was taken out onto the streets of the city's historic centre Sunday for the first time in 150 years to ask God for protection.

As in the times of smallpox, Roman Catholics joined in prayer against the ongoing flu epidemic, including cases of swine flu, that has left 149 people dead in the country in less than a month.

Geneva - The World Health Organization (WHO) has raised its pandemic alert level for influenza one step to phase 4 in light of the developments of the swine flu outbreak, an official said Tuesday in Geneva. Margaret Chan, director general of the WHO, made the decision following an extradited meeting of the organization's emergency committee but did not recommend restrictions on travel.

The WHO's Keiji Fukuda said the heightened alert was a "sign of a step towards pandemic influenza but a stage that says we are not there yet."

Brasilia - The Brazilian government complained Monday that Mexican authorities took too long to inform other countries of its swine flu outbreak. Brazil has so far not reported any cases of swine flu, the Health Ministry said.

"In such cases as these there cannot be such a delay in notification. Brazil has a habit of not hiding serious public health cases," said Agenor Alvares, general director of the public Agency for Health Surveillance (Anvisa).

Washington - The US Centres for Disease Control and Prevention (CDC) was to issue an advisory against non-essential travel to Mexico - the epicentre of the global swine flu outbreak - acting director Richard Besser said Monday. "This is out of an abundance of caution," he said, adding that the Atlanta, Georgia-based CDC had confirmed 26 deaths in Mexico were a result of swine flu. "This is a small fraction of what they are seeing," Besser warned.