The SARS epidemic of 2003 was caused by a corona virus, but it was not the Bird Flu. One of our smart readers caught my mistake. I was confused by my recollection of the high mortality of bird flu, like corona virus infections.
The H5N1 and H7N9 influenza A strains cause bird flu in humans. Problem of tramsmission from bird populations to humans started with the first case in 1997, and mortality is 50 percent or more. No pandemic has occurred but the disease is considered epidemic since it has been seen in a number of countries. The virus is still around and in the bird population with high bird mortality. Just doesnt jump to humans easily.
http://www.webmd.com/cold-and-flu/what-know-about-bird-flu
Now we have a corona virus with high mortality called the Middle East Respiratory Syndrome CO V.
Also antibodies have been found in camels. More than likely the barrier to a jump to humans will make it less likely to cause an epidemic
Just like we found with SARS, which had a limited spread and impact.
http://www.who.int/csr/disease/coronavirus_infections/faq/en/
Thanks, I was mistaken on the bird flu, thought the chicken flu SARS virus was called the bird flu at the time, not so. I was thinking corona virus though, because it is different in size and virulence and also its tramsissibility.
John, I am sure you meant something other than bird flu, which is a flu virus, just like human flu. Bird flu getting into pigs stirred the press at about the same with SARS virus discovery in Asia — maybe that was the source of confusion? SARS was indeed caused by a coronavirus.
Bird flu types differ from human types in their preference to 2,3-Gal-linked sialic acid which are more common in birds than in humans and many other mammals, whose receptors are 2,6-linked. Pigs are peculiar in that they have both type of receptors and so they can be co-infected with bird flu and human flu, giving rise to new flu types.
http://en.wikipedia.org/wiki/Avian_influenza