Saturday, November 22, 2008

Birds and Cold Viruses


Human Rhinovirus

I was a little skeptical when I saw the story tag "Journal article blames birds for giving us the common cold virus 200 years ago" on littlebirdhome.com this morning. The tag links to an article on Medical News Today "Common Cold Virus Came From Birds." This is a slight technical error between the common cold virus and a common cold virus - there are a multitude of viruses responsible for giving us the common cold.

If you google "common cold virus birds" or something similar, you'll already find hundreds of websites referring to an article published in the December issue of the Journal of General Virology on the subject. Well, it may be true that Human metapneumovirus is closely related to Avian metapneumovirus from an evolutionary standpoint, and is the second most common cause of colds in children, but the primary culprit (possibly up to 70% of all colds) are rhinoviruses.

The problem is, as I've recently observed in other stories published on the Internet, many us are headline and bold-print readers when it comes to digesting our daily quota of news. Whether jokingly or serious, I just know members of the birding community are going to hear other people vilify birds for giving us colds. Already, here's a comment I found at the end of one article on this story:

I am beginning to wonder if the migrating crows brought something with them. There are so many people coming down with a bad cold followed by a hacking cough that just lingers for over two weeks. Yes, I know how viruses travel, and that there are a bunch of new colds every season, but this time it seemed to coincide with their arrival in this area.

Coincidence! Rhinoviruses are with us throughout the year and mutate very quickly. So, you can get a common cold any time of the year, but they're more prevalent from September to April because we're spending more time indoors in close quarters with other people - transmission opportunities increase dramatically. True, birds migrate in the fall and spring, but an adequate explanation is no guarantee it is the correct one. The point is, birds are not presently transmitting a pandemic virus to people that causes common cold symptoms; the two forms of metapneumovirus are genetically related. That's the story!