The deaths of 83 people in Mexico, 14 in the United States, two in Canada and one in Costa Rica have now been linked to swine flu. But WHO's flu chief said the virus hadn't yet reached the level of pandemic and said a global outbreak designation would change little about how governments are already responding.

"We are comfortable that countries are doing the kinds of public health actions that they need to be taking right now," Keiji Fukuda said Tuesday during a press conference.

Governments continued to take steps to try to limit the virus' spread.

In Australia, about 2,000 passengers from a cruise ship that docked in Sydney were advised to quarantine themselves for a week after at least nine cases of swine flu were confirmed on board. The passengers disembarked Monday after nine days cruising the Great Barrier Reef.

Singapore's health ministry said it was searching for passengers on a flight from New York after a 22-year-old woman on the plane came down with the country's first case of swine flu.

In Chile, health authorities were keeping a 38-year-old woman in isolation with severe symptoms. Health authorities in Panama reported three new cases Tuesday, for a total of 79.

According to WHO's current pandemic criteria, the world is now in phase 5, meaning a global outbreak is imminent. To reach phase 6, the highest level, the agency's current definition requires established spread of the disease in a region beyond North America.

Fukuda said other countries would have to report big outbreaks similar to those seen in Mexico and the U.S. before WHO raises its pandemic alert. More than half of the swine flu cases are in the U.S.

Twenty schools reopened Tuesday in New York City, including one whose assistant principal was the first person in New York City to die of swine flu. But five more schools were closed, and the confirmation that two people who died Friday had swine flu brings the number of deaths possibly caused by the virus to four.

"Our hearts go out to their families," Health Commissioner Thomas Frieden said.

The outbreak began more than a month ago when hundreds of students at St. Francis Preparatory School in the Fresh Meadows section of Queens became sick.

The four known victims also had other underlying health conditions, Frieden said.

The two people whose deaths were disclosed Tuesday were a 41-year-old Queens woman and a 34-year-old Brooklyn man. Lab results confirmed that they had swine flu, but the exact cause of their deaths will be determined by autopsies, Frieden said.

Meanwhile, the Queens school whose assistant principal became the first New Yorker to die of swine flu again bustled with activity Tuesday.

The Susan B. Anthony Intermediate School, Intermediate School 238, was among 20 schools or programs that reopened after being shuttered as a precaution amid the city's 330 confirmed cases of swine flu.

"We just want to keep things moving," said principal Joseph Gates as he helped load two buses of students headed for a school trip to Washington, D.C.

Mitchell Wiener, I.S. 238's assistant principal, died May 17. A woman in her 50s died Saturday. The names of the swine flu victims other than Wiener have not been released.

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Associated Press writer Deepti Hajela contributed to this report.

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On the Net:

World Health Organization, http://www.who.int

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