Human noses too cold for bird flu

BBC ^ | May 14, 2009 | BBC

[CutePuppy]

Human noses too cold for bird flu

Bird flu may not have become the threat to humans that some predicted because our noses are too cold for the virus to thrive, UK researchers say.

An Imperial College London recreation of the nose's environment found that at 32 degrees Celsius, avian flu viruses lose function and cannot spread.

It is likely that the viruses have adapted to suit the warmer 40 degree environments in the guts of birds.

A mutation would be needed before bird flu became a human problem, they said.

Published in the journal PLoS Pathogens, the study also found that human viruses are affected by the colder temperatures found in the nose but to nowhere near the same extent.

In effect, human viruses are still able to replicate and spread under those conditions, the researchers said.

Both viruses were able to grow well at 37 degrees - human core body temperature and equivalent to the environment in the lungs.

They also created a mutated human flu virus by adding a protein from the surface of an avian influenza virus.

This virus - an example of how a new strain could develop and start a pandemic - was also unsuccessful at 32 degrees.

Mutations

Study leader Professor Wendy Barclay said it suggested that if a new human influenza strain evolved by mixing with an avian influenza virus, it would still need to undergo further mutations before it could be successful in infecting humans.

.....

She said swine flu - which was spreading from person to person, seemingly through upper respiratory tract infection - was probably an example of a virus which had adapted to cope with the cooler temperatures in the nose.

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[CutePuppy]

H5N1 (and very likely H1N1, a "swine flu" virus) are not easily transmitted to healthy humans, and thus are far less dangerous than seasonal human influenza viruses and their variable, mutated strains, which kills or temporarily disables several magnitutes the number of people, every year.

So much for pandemic panic. And to all of you, puppies - let's be careful out there, and keep your noses cold and wet.

[muawiyah]

Viruses don't care if you are "healthy" ~ they do not have a "health" detector anyway.

Sick people and healthy people can catch flu ~ swine flu, or old-fashioned flu cooked up over at the neighbors.

I think you are confounding "catch" with "kill". Healthy people may well not have secondary conditions that are assisted in killing us if we catch flu.

[CutePuppy]

Forgive my shorthand, then. By virus being “not easily transmitted to healthy humans” I obviously meant people not being seriously affected by such virus to the point of disease... in the same meaning as “catching a virus” usually means having already developed the symptoms of the disease rather than having copious quantities of virus deposited on the hands and washing them away with soap.

Obviously, “healthy humans” are the ones who at the time don’t have weakened immune system - for many reasons, including stress or other diseases - that makes them more susceptible to be affected by virus.

[Riodacat]

A mutation would be needed before bird flu became a human problem, they said.

And, like that would never happen, eh?

[BlueStateBlues]

Colder than a witch’s. . .nose.

[freebilly]

A mutation would be needed before bird flu became a human problem, they said

Gee, that could never happen........

[freebilly]

Should’ve read your post before responding....