The temperature's falling and out come scarves, mitts and hats. But besides cooler weather and a wardrobe change, it also means it's cold and flu season. For most Canadians, sneezing and sniffles are unpleasant inconveniences. But for the hundreds of thousands of people living with chronic obstructive pulmonary disease, or COPD, a cold or flu can be very serious. It can trigger a flare-up or lung attack, which can result in hospitalization, restricted mobility and even death.