One interesting thing I've noticed. We Malaysians (Singaporeans too, actually) so freely use the words 'flu' and 'cold' interchangeably. This came up when this Malaysian medical student on elective here casually told me he was feeling unwell and had the flu (kinda ironic, considering he's doing a pulmonary rotation)(sorry buddy! )
But it's true. A cold is a nonspecific upper respiratory tract infection. Usually viral. Flu on the other hand, implies influenza. Something with a mortality rate of up to 10% in the elderly. Not something you wanna fool around with.
I realized this years ago when I callously used the word 'flu' when I meant 'cold'. My consultant almost sent me home. And when dad was visiting 2 years ago and he told a pregnant friend of mine that he had the flu, she literally jumped 2 feet back.
We all do it. Even doctors, freely interchanging these words. But something to think about the next time you're telling someone about your illness.