SAN JOSE, Costa Rica - Costa Rica reported the death of a 53-year-old patient with the H1N1 virus on Saturday, the first death from the epidemic outside of the North American mainland, while a third death was reported in the U.S. and Japanese authorities scrambled to limit contacts with their first confirmed cases of the disease.
The Costa Rican man, who also had diabetes and chronic lung disease, was one of eight swine flu cases in the Central American country that have been confirmed by the U.S. Centers for Disease Control and Prevention, Health Minister Maria Luisa Avila told The Associated Press.
In Seattle, the Department of Health said a man in his 30s, who had underlying heart conditions, died last week with what appears to be complications of swine-origin influenza.
Mexico has recorded 48 H1N1 deaths, three have been reported in the United States and Canadian officials say a woman who died last month had the virus.
Avila said officials had been unable to determine how the Costan Rican man who died became infected, but she said he had not recently travelled abroad. Many flu sufferers in other countries have been linked to recent trips to the United States or Mexico.
In Japan, authorities quarantined a high school teacher and two teenage students who returned Friday from a school trip to Canada after they tested positive at the airport. Australia and Panama joined the list of countries with confirmed cases of swine flu.
The chief medical officer for Alberta, Andre Corriveau, said Friday that a Canadian woman who died on April 28 had been infected with the H1N1 flu virus. The woman, who was in her 30s, had other health problems.
Officials said she had not left the country recently, but could not confirm whether she was in contact with anyone who had recently returned from Mexico.
The World Health Organization has that said based on past outbreaks, it is possible that a third of the world's population, or about two billion people, could become infected if this outbreak turns into a two-year pandemic. Independent experts agreed it was possible but pointed out that many would not show any symptoms.
People with chronic illnesses are at greatest risk for severe problems from flu, along with the elderly and young children. So far, however, most of Mexico's victims have been aged 20 to 49 and the disease has claimed few lives among the very young and very old.
A report by the CDC said the two U.S. swine flu deaths -- a toddler and a pregnant woman who both died in Texas -- each suffered from several other illnesses.
Mexico's federal Health Department said Friday that about a quarter of those who died there were obese or suffered from diabetes, while 11 per cent had cardiovascular problems and 9 per cent smoked.
It listed no complicating factors for most of Mexico's first 45 deaths, however, and none of them were reported to have respiratory ailments or other infectious diseases.
Hard-hit Mexico said only one new infection has been reported in the past four days and the country was gradually lifting a nationwide shutdown of schools, businesses, churches and soccer stadiums. It raised its count of confirmed cases to 1,626 based on tests of earlier patients.
Japan's national laboratory confirmed the virus in a teacher and two students who arrived in Tokyo Friday on a Northwest Airlines flight from Detroit. The Health and Welfare Ministry said it was working with the World Health Organization to contact at least 13 people on that flight who had gone on to other destinations in transit.
Local news media reported that as many as 11 people on the flight avoided screenings for swine flu.
Japanese Health and Welfare Minister Yoichi Masuzoe acknowledged it would be difficult to trace all those who came into contact with the three infected Japanese, who visited Oakville, Ont., on a home-stay program with about 30 other students. The three were isolated and recovering at a hospital near Narita International Airport.
"There are limitations to what we can do, but we will continue to monitor the situation and strengthen or relax such measures as needed," he told reporters.
Public broadcaster NHK TV urged people who were aboard the flight to call a special telephone number for consultations. So far, 49 have been traced and will be monitored for 10 days, officials said.
But a handful of cases have cropped up elsewhere in the region, including in South Korea and Hong Kong. The Chinese territory quarantined more than 200 people in a hotel after confirming its first case in a guest a week ago. They were released on Friday.
Australia reported its first case on Saturday in a woman it said was no longer infectious. She first noticed her symptoms while travelling in the United States, federal Health Minister Nicola Roxon told reporters.
New Zealand -- the first country in the Asia-Pacific region to confirm cases -- reported two more on Saturday for a total of seven. The two high school students returned last month from a school trip to Mexico. Six of the country's cases were in students and a teacher on that trip; the seventh travelled on the same plane as the group.
