Yes, the scope of the avian flu epidemic in the Fraser Valley staggers the imagination. How do we digest the idea of 19 million birds, mostly chickens, all being killed over a matter of a few weeks? It's hard enough to imagine 19 million chickens living, much less all dying at once, between here and Hope. How did there get to be so many of them, so close to us, so close to each other, so vulnerable to viral infections? But if you really want to test your mental elasticity, try the official version of what happened, which is that the $850-million-a-year B.C. poultry industry was brought to its knees by a couple of mallards and some chickens with the nasty habit of walking around outside. First the Canadian Food Inspection Agency identified wild waterfowl as "natural reservoirs for the influenza viruses," and "the likely vector that first brought the disease into the region," a refrain repeated by all the major media outlets. The CBC web page on avian flu reported that "wild birds - ducks, in particular - carry the virus, but aren't killed by it. They can spread the virus to farm birds through direct contact or through contaminating water supplies." Wild birds 'must die' No surprise then, to hear a CBC radio phone-in caller demanding to know why, if the disease came from wild birds, they weren't going to be killed too. Then there was the April 6 Vancouver Sun editorial, "Lessons to be learned from avian flu ordeal," which called for conservation authorities to take steps, "given the threat wild birds pose to commercial poultry, and potentially to people." Happily the writer stopped short of urging a wild bird kill, since "it's not possible, nor desirable, to kill every wild bird in the affected region." The stakes are certainly high enough. If the avian flu virus comes into contact with human influenza virus, it could unleash a disease against which we have limited defenses. In fact, the stakes are so high, it's worth questioning the prevailing mindset that all is well within the poultry industry, and what's good for the industry is good for us, and for the chickens. Chickens spared gas for knife An example: the happy news reports that came out on April 7, when Canadian Food Inspection Agency officials announced that most of the broiler chickens, which make up about 15 million of the 19 million birds, would be would be "salvaged." This was indeed good news, although not necessarily for the chickens, since it only meant that healthy flocks of broiler chickens would be going to slaughter by the normal route -- a truck ride in a crowded cage to the processing plant. Had they not been "salvaged," they'd have been gassed on the dim and crowded barn floors where they spent their lives -- which, from a chicken's point of view, might well be preferable. CFIA veterinarian Cornelius Kiley, speaking at a press conference on April 8, expressed his confidence in the poultry producers. "It's a sophisticated industry," he said. "They know what they're doing." What they're doing right now, of course, is pointing their fingers at wild birds and promising heightened "bio-security." Once happy together Yet ever since chickens arrived in the Fraser Valley, at least 120 years ago, migrating ducks have shared pastures, ponds and avian flu viruses with them. It's true, as Ron Lewis, chief veterinarian for the province, points out, that for much of that time we knew very little about avian influenza. An outbreak that killed a flock or two might not have been recorded, or might have been ascribed to some other cause. During the last 40 years, on the other hand, we have known about influenza, and this is the first time we've faced a serious outbreak. In fact, until now, barnyard chickens, like the wild birds, have been able to carry avian flu viruses and remain symptom free. Here's another puzzling fact. The outbreak did not begin where we might have expected it, in a backyard flock or on a free-range farm, where chickens might be exposed to wild birds. Instead, sick birds first turned up in a broiler-breeder operation, where the chickens are protected not only from contact with wild waterfowl but from venturing outside at all. Broiler breeders lay the eggs that hatch into the chickens we eat. A broiler-breeder barn, for those who have never seen one, is like a very large and densely populated avian live-sex show, with thuggish roosters and harried hens. Although crowded, the chickens are not in cages -- they're allowed more square footage than any other commercially raised chickens short of free-range. Big barns breed 'better' bugs We may never know how the H7N3 virus got into the barn -- car tires, boots, carried on the wind? Nor do we know when. The birds were a year old when some of them started refusing their feed and a few more than is normal started to die, so the virus could have been present in the barn for several months. We do know that when it was first detected it was a low-pathogenic form, meaning that it caused illness but not a high mortality rate. While officials deliberated on how best to destroy the flock and sterilize the barn, the flu broke out in another barn on the same farm, among younger birds, and began to kill in earnest. By then it had mutated into a new and powerful high-pathogenic form. Mutation is something viruses do with amazing speed and regularity. Everything we know suggests that the broiler-breeder barn presented perfect conditions for mutation: a large number of genetically homogenous birds held at close quarters under considerable stress - and you haven't seen stress until you've seen a hen in a broiler-breeder operation. At first the virus moved to other broiler-breeders, then it moved into a broiler barn, where day-old chicks grow into boneless, skinless breasts and thighs. Here, chickens in flocks of 20,000 or more in a single barn are free to run around, but the average space allotted them is less than what you see when you look at a sheet of 8.5-by-11-inch paper. That's big enough for a day-old chick, rather less comfortable for a grown bird. High stakes demand care So far, a few voices, among them organic poultry farmers and Green Party leader Adriane Carr, have argued that avian flu is a wake-up call that demands a serious look at poultry production in the Fraser Valley. They haven't had much play in the mainstream media, which is a shame. After all, it was in one of the sophisticated barns of this sophisticated industry that a previously harmless virus turned into a highly pathogenic killer with the potential -- slight, but still there -- of jumping the species boundary and killing us too. Perhaps now we might turn our attention away from wild waterfowl, and look instead at the profitable vulnerabilities built into our food supply. Vancouver writer Eve Johnson is the author of "Eating My Words", a collection of essays on food published by Whitecap Books. She eats chicken.