Doubt cast on Mexican flu toll

The World Health Organization raised its alert system to a step away from full-blown pandemic level yesterday, though new evidence circulating among scientists suggests that far fewer people have died from the swine flu in Mexico than thought.
WHO officials said a pandemic is now inevitable, and urged countries to go on high alert against the new H1N1 virus, saying the bug's spread will affect "all humanity."
Yet an in-depth analysis of some of the 150 or so Mexican deaths linked to the flu found that few were actually caused by the new flu bug, suggesting a relatively modest fatality toll, said a well-placed Canadian infectious-disease expert.
The number of Canadian cases, meanwhile, jumped to 19 with three more each in B. C. and Ontario. Like the Canadian patients identified earlier, they were all described as having relatively mild infections.
Canadaearnedinternational praise at the same time for the scientific support it has lent to the WHO and Mexico, including agreeing to test yesterday a rush shipment of 200 Mexican blood samples at microbiology labs in Winnipeg.
In Geneva, Dr. Margaret Chan, director-general of the UN agency, said she had decided to move the pandemic alert scale to phase five, while another WHO official said a pandemic is now inevitable.
Dr. Chan urged that the world work together to fight the virus, with affluent nations donating anti-viral medication to developing countries, which she said are always hit the hardest by such diseases.
"Influenza pandemics must be taken seriously precisely because of their capacity to spread rapidly to every country in the world," said the Canadian-educated official.
"This is an opportunity for global solidarity as we look for responses and solutions.... It really is all of humanity that is under threat during a pandemic."
Pandemic phase five denotes a novel virus that has shown sustained transmission between humans in at least two countries of a particular region -- Mexico and the United States in this case.
Level six -- the pandemic phase -- involves such transmission in at least one additional country in another region.
Dr. Chan, though, said the most important unanswered question about the virus -- a combination of pig, bird and human flu genetics -- was how severely it will affect people.
The close to 1,900 cases and 150 or more deaths linked by Mexico to the microbe have inspired much fear. But pathologists and other scientists are now thoroughly investigating those deaths through autopsies and tests, and uncovering a different picture.
Dr. Gerald Evans, head of the Association of Medical Microbiology and Infectious Disease Canada and a member of a federal pandemic-planning committee, said he was told that of about 25 "highly suspicious" deaths investigated, only seven were found to be a result of the swine flu. "There was a lot of speculation and what seemed to be evidence there were dozens and dozens of deaths. Careful analysis showed these people likely died of something else, and not flu," he said.