I have a small flock of chickens and a wife in the medical field. Naturally, in these uncertain times, that leads to discussion about avian influenza, aka bird flu. My wife recently brought home a copy of the World Health Organization's (WHO) (www.who.int/en) February 2006 “Avian Influenza Fact Sheet.” And the question she also brought home was: What are we going to do with our chickens when the virus reaches North America?
Basically, avian influenza is “an infectious disease of birds caused by type A strains of the influenza virus,” according to WHO. Unfortunately for all of us, it's now considered a worldwide disease. Apparently, all birds are considered susceptible to the infection and many wild birds carry the viruses without signs of harm.
For those of us who live along the migratory bird path (think Bosque del Apache), therein lies the greater problem. Some nice but infected birds fly over from Asia to Alaska, they hang with some other birds—who contract the disease as carriers—then those birds enter the North American flyway for migratory birds. Those birds stop to drink and eat down by your friendly, neighborhood chicken coop (I have lots of ravens that visit daily; I like them too because they keep the hawks away and are beautiful birds in their own right). The visiting carrier birds pass the virus to the chickens and some chickens may develop the disease. According to WHO, “At least some species of migratory waterfowl are now thought to be carrying the H5N1 virus in its highly pathogenic form and introducing it to new geographical areas located along their flight routes.
“The viruses cause two distinctly different forms of the disease [in poultry]—one common and mild, the other rare and highly lethal. In the mild form, signs of illness may be expressed only as ruffled feathers, reduced egg production, or mild effects on the respiratory system. Outbreaks can be so mild they escape detection unless regular testing for viruses is in place.” This means large commercial operations actually have an advantage over small backyard poultry flocks.
Thus far, the virus' success has been honor roll material: First, it spread from bird to bird, then from bird to chicken, which is more difficult, and now there's a downright noteworthy spread from chicken to human, and thus we await the final killing blow—from human to human. That's what makes for a pandemic. Humans travel globally, and if the virus can travel with us, we've got problems. Even locally, if you're infected, just going down to the grocery can infect everyone there, or if you don't have it yet, you can be infected by someone else on your trip to buy canned beans.
WHO states that the “most important control measures are rapid culling of all infected or exposed birds.” They also state that outbreaks in backyard flocks are the hardest to control and offer a heightened risk of human exposure and infection. This is dangerous for New Mexico in particular because we have prevalent smaller poultry flocks mostly in “rural and periurban areas,” adding further risk.
Lastly, like most virulent diseases, the young and old parts of our population are the most susceptible, adding insult to injury. But, according to WHO, there is some good news for our state, “The highly pathogenic H5N1 virus can survive in bird feces for at least 35 days at low temperatures (4 degrees Celsius/39.2 degrees Fahrenheit). At much higher temperatures (37 degrees Celsius/98.6 degrees Fahrenheit), H5N1 viruses have been shown to survive, in fecal samples, for six days.” I guess New Mexico's blistering-hot summer is worth looking forward to, after all.
But the very worst news will be reserved for my chickens. My wife keeps asking, “What are you going to do with them?” And I keep telling her, “It's nothing for you to worry about, I'll take care of it. All I'll need is a bag of lime.”