By Staff
In last week's column on swans I mentioned that a bird flu virus had been found in Michigan swans last year. Just the name bird flu strikes fear in our hearts because of the Asian bird flu, labeled H5N1, which is running rampant throughout Asia and is rapidly expanding into Europe and Africa.
It has not yet reached the Western hemisphere. Though it has caused some human deaths, it has mostly impacted wild birds and poultry but experts fear it could mutate into a more human virulent strain and quickly become a worldwide pandemic. In chasing down the avian flu found in two swans over by Detroit last August I found out there's a lot more to the flu bug than I care to know or can even comprehend. Evidently avian flu comes in a variety of forms and is not uncommon in some form or another in North American birds. What's causing all the fuss over the Michigan swan's bug is that it is the H5N1 avian flu virus. However, don't panic yet.
Apparently there are two types of H5N1 bird flu viruses. The one wreaking all the havoc across The Pond is called a high pathogen H5N1. The one found in the Michigan swans is a low pathogen H5N1. Since I've already been to the dictionary to look up pathogen I'll save you the trip. A pathogen is any micro-organism or virus that causes disease. Thankfully, the one here in North America is low pathogenic, meaning it doesn't easily spread. The U.S. Dept. of Agriculture, Dept. of Health and others are insisting it poses no threat to humans or the poultry industry.
Our two swans don't have a corner on the North American H5N1 bird flu market. Some time ago scientists began monitoring our birds fearing the dreaded Asian bird flu will make it over here and last year they also found other cases of the low pathogenic H5N1. Several mallard ducks in Maryland and Pennsylvania were found with the virus as were a mallard in British Columbia and a goose in Prince Edward Island. Officials emphasize that since 1975 this same strain has been found in U.S. birds six times so there's no need to get our knickers bunched up about it.
That said, some folks aren't taking it so lightly. Scientists at the Recombinomics Company that does testing on avian flu (and a jillion other diseases) say the low pathogenic H5N1 easily recombines with the high pathogenic bad boy to become very virulent. A number of scientists suspect the low pathogenic H5N1 is a lot more prevalent in North American birds than is currently suspected, it just hasn't been found with such limited testing. Should the bad Asian version make it into North America this would give it an easy path to very quickly run rampant.
So what are the chances of the Asian variety coming onshore here? Many experts say that it's not a matter of if, but when. Billions are being spent here and abroad to prevent movement of the disease within the poultry industry but we're finding that's not the only avenue. Many wild birds, especially migratory waterfowl, are highly susceptible to Asian bird flu and may be the largest cause of its rapid spread across Asia, Russia, Europe and down into Africa. And what sits just a stone's throw across the Bering Sea west of Alaska? Siberia. Birds migrate all up and down the Asian and Siberian coast line. Some, such as Tundra swans, also hop over to the Alaskan side on a routine basis. Once a bird carrying high pathogenic H5N1 comes to our side and commingles with the millions of our geese, ducks, swans, cranes, et. al. that migrate from the lower 48 to Alaska each year the barn door would be kicked wide open. If, as some suspect, many of our birds all across the country are already carrying the low pathogen version the two may recombine and the dreaded Asian bird flu could zip throughout the continent in a swan’s heart beat. But, that's a lot of what ifs so let's not get too excited yet. Carpe diem.