Alaska spokeswoman Bobbie Egan says about 270 passengers were affected by cancelled flights. Another 14 flights were cancelled Sunday due to bad weather.
Egan says a "very unusual" cold and flu season hit the airline's Pacific Northwest hub, and the entire region was affected.
Egan says pilots and flight attendants who were off-duty have volunteered to work while their colleagues are out sick.
The airline forecasts a less-busy Tuesday, and says it probably won't have to cancel any more flights because of illness.
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