Sunday 6 January 2013

Avian flu virus learns to fly without birds' help

New Scientist article January 2013

Avian flu virus learns to fly without birds' help

A strain of bird flu that hit the Netherlands in 2003 travelled by air, a hitherto suspected by unproven route of transmission

POTENTIALLY fatal bird flu viruses can spread on the wind, a hitherto suspected but unproven route of transmission.

Usually, people catch bird flu through close physical contact with each other or, much more commonly, with infected poultry.

The newly identified capacity for wind to spread it opens up a potential route by which the viruses can spread between farms.

The finding came about after Dutch researchers studied an outbreak of the avian flu strain H7N7 in poultry on Dutch farms in 2003, which resulted in 89 confirmed human infections including one death.

Computer models showed that wind patterns at the time of the outbreak explain how different genetic variants of H7N7 ended up on different farms (Journal of Infectious Diseases, doi.org/j3b).

H5N1 is the most harmful strain of avian flu, having killed 360 of 610 infected people since it was discovered in 2003. The fact that a related strain can travel on the wind suggests that H5N1 can too, says Marion Koopmans of the Dutch National Institute for Public Health and the Environment in Bilthoven, who coordinated the research project. "You must assume that this same potential is there for H5N1," she says.




West Antarctica is warming fast

January 2013 New Scientist

West Antarctica is warming fast
The vulnerable ice sheets of West Antarctica are warming as fast as anywhere else on Earth, threatening massive sea level rise

THE ice sheets of West Antarctica are warming much faster than we thought, suggesting swathes of it could melt and send global sea levels soaring.

Climatologists have struggled to work out whether Antarctica is warming, and how quickly, because it has few weather stations and the records from some are incomplete.

David Bromwich of Ohio State University in Columbus and his colleagues filled in the gaps for one key station using statistics and data from a climate model. They conclude that temperatures since 1958 have risen about 0.46 °C per decade – more than twice as fast as previously thought (Nature Geoscience, doi.org/j351).

But Michael Mann at Penn State University in University Park says that warmer ocean water flooding in underneath the sheet poses a greater threat.




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Sketches from scratches is a provocative blogspot that has grown out of the Wuh Lax experience. It is eclectic, which means that it might consider just about anything from the simple to the extremely difficult. A scratch can be something that is troubling me or a short line on paper. From a scratch comes a verbal sketch or image sketch of the issue or subject. Other sites have other stuff that should really be of interest to the broad reader. I try to develop themes, but variety often comes before depth. ... more!