Factory farming obviously meant that the disease spread like wildfire, so it is relevant.
I personally think factory farming should be abolished. It is the worse form of animal cruelty. If people ate more expensive, humanely produced meat, but far less of it; and relied on other cheaper food sources, such as vegetables and pulses to their diet, then we would be a healthier nation.
Whilst people insist on eating loads of poultry and loads of meat and are blinkered to the cruelty involved, then factory farming will continue.