Our Desire for Inexpensive Food Is Putting Us in Danger
A dairy worker in Texas contracts H5N1 bird flu after contact with infected cows, and suffers eye inflammation. Weeks later, a dairy worker in Michigan begins to cough and then tests positive for the virus. A ferret in a cage (ferrets are often used as study proxies for humans) becomes infected with the virus by airborne transmission from a sick ferret in a nearby cage. These data and other recent cases of H5N1 suggest that the virus might be evolving to spread more easily to — and among — people.
One implication is that while U.S. health authorities say the risk to the general public remains low, that risk could increase quickly. Another implication, less obvious but worth pondering, is that our collective appetite for on-demand inexpensive meat and dairy is leading us toward another catastrophic pandemic, not just pink eye and coughing in a few people.
It is fair to criticize government bodies, such as the U.S. Department of Agriculture, the Centers for Disease Control and Prevention, and state departments of health and of agriculture, for their laxity, tardiness, lack of transparency and inefficacy in dealing with the dangers of H5N1 on dairy farms. For instance, why isn’t blood testing for signs of the virus among dairy workers now mandatory in all U.S. dairy operations? Why isn’t there widespread use of protective equipment? Why haven’t there been earlier and broader requirements for the testing of cows?
But we should reserve some of the blame for ourselves. Americans are eager customers of the products that industrial-scale animal husbandry provides: milk, eggs, beef, chicken and pork. They arrive on our supermarket shelves wrapped in plastic or in cardboard cartons from vast factory farms perfectly suited to serve as petri dishes for the evolution of novel pathogens — novel to humans, anyway. We have surrounded ourselves with chattel animals, raised and milked and fattened and slaughtered and plucked and butchered in staggering numbers. It’s no surprise that sometimes they give us their viruses.
One contributing factor to the looming threat of H5N1 is that it has spread among poultry flocks. Quantity of hosts correlates with the quantity of opportunities, and there are, by one authoritative estimate, about 34 billion chickens alive on Earth at a given moment. Most of those are in big commercial operations. What makes such scales dangerous is not the inhumanity involved (that’s a separate issue) but the abundance and concentration of animals. Evolution is a numbers game like roulette, though with higher stakes, and for a virus, even in a single host, the numbers are often huge.
One particle of a flu virus replicating in an animal might produce 100 billion more flu particles in a few days. Those offspring will contain many random mutations, which are raw material for evolution. The more spins of that roulette wheel, the greater cumulative chance that the pearly ball will land on a number that breaks the bank.
