Flu update

Hong Kong is preparing for the worst.
Remember the Hong Kong flu?
They don't take these things lightly.

The authority which manages all of Hong Kong's public hospitals fears an explosion of bird flu cases in the city early next year, a Chinese-language daily reported on Saturday, quoting a source at the authority.

"Spring is the peak season for human influenza. Once the human influenza virus mixes with bird flu, it will pose a big threat," Wen Wei Po said in a front-page story, quoting an unidentified source at the Hong Kong Hospital Authority.

"If bird flu explodes in the community, the first wave will be very severe. It will pose the biggest threat to young people," the pro-Beijing daily said.

Experts fear that the H5N1 bird flu virus could mutate and become easily transmissible between people, setting off a pandemic in which millions might die. The virus in its current form has killed around half of the people it has infected.

A study, published in the online medical journal Respiratory Research, suggested that if H5N1 did cause a pandemic, it could disproportionately affect the young and healthy as compared to seasonal flu, which kills many elderly but few young adults. In Hong Kong, the seasonal peak for human influenza is between January and March.

This link comes from H5N1 Blog.

Those interested in science might be interested in this.

The more you understand of this report from Respiratory Research, the less you'll like it: Proinflammatory cytokine responses induced by influenza A (H5N1) viruses in primary human alveolar and bronchial epithelial cells.
[...]
If I understand what they're saying, H5N1 has a talent for provoking the immune system into inflaming and destroying the lung tissue where the virus is thriving. The abstract goes on to say that recent virus strains from Vietnam are even better at inducing "chemokines" than the original 1997 strain of H5N1.

Or this via another bird flu blog.

Bird flu might cause such severe disease and kill so many people because it makes the immune system 'overreact', say researchers.

They say that suppressing the immune response could be a way to treat infection by the H5N1 virus, which has killed 64 people in Asia — about half of all confirmed cases.

In a study published online today (11 November) by Respiratory Research, the researchers showed that lung cells infected with the virus produce considerably more 'messenger' chemicals than cells infected with a normal human flu virus.

These chemical messengers alert the immune system to send white blood cells to attack the source of infection.

The production of so many messenger molecules could explain why H5N1-infected people's lungs are "full" of a kind of white blood cell called macrophages, says lead researcher Malik Peiris of the University of Hong Kong.

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