Thursday, November 30, 2006



It's only a theory for now, but it reads like something out of a nightmarish horror novel nobody has yet written (as far as I can research online). So what happens if the 1918 bird flu virus comes into contact with today's H5N1 strain? Do they cancel each other out? Or do they recombinate to deliver us the long-feared second global pandemic in 100 years?

From Bloomberg :
Influenza viruses may be preserved in glaciers and Arctic ice for thousands of years and released into the environment when the frozen water is thawed, potentially touching off lethal pandemics, researchers said.

Global warming may speed the release of the microbes, increasing the frequency of outbreaks, according to a study in the December issue of the Journal of Virology.

The study is based on tests of water and ice from three lakes in Siberia, where large populations of migratory waterfowl breed before traveling to North America, southern Asia, Europe and Africa.

The finding may help explain the constant emergence of influenza A-type viruses that cause seasonal epidemics and occasionally set off pandemics capable of killing millions of people. Disease trackers are monitoring flu viruses amid an outbreak of the H5N1 strain, known to have infected 258 people in 10 countries in the past three years, killing 153 of them.

The spread of H5N1 in late 2003 has put the world closer to another pandemic than at any time since 1968, when the last of the previous century's three major outbreaks occurred, according to the World Health Organization.

Many species of aquatic birds flock to Siberia and other areas near the Arctic Circle for breeding during the Northern Hemisphere's summer before flying south during the fall.

As the birds visit lakes along their paths they shed viruses into the water and onto any ice present, and drink water containing viruses discharged by other birds or released from the ice by thawing, the authors said in the study.

In previous studies, the authors, who include researchers from Israel's Bar-Illan University and the Russian Academy of Sciences, documented the preservation of viruses, bacteria, and fungi in glacial ice for as long as 140,000 years.

Surveillance of Arctic lakes may help disease trackers predict which flu strains will cause future outbreaks and shape long-term vaccination strategies, the researchers said.

Until refreezing takes place, viruses of both present and past strains may be contracted by the waterfowl, allowing old and new viruses to continually recombine, the study said.

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