Question: Can you get or spread a cold by shaking hands (at work, for example)?
Answer: Loss of time at work is a very important side effect of having the cold or the flu. However, it's important not to go back too soon because you do need your rest and you do need to recuperate.
The most important thing, however, is that you're at risk for transmitting your infection to your colleagues, so you want to be a good neighbor if you do go back to work.
It's very important to realize that the cold and the flu viruses are transmitted from hand to hand or through sneezing or coughing and so you want to make sure that you wash your hands when you're at work and that you don't shake hands with people or cough or sneeze on them inadvertently.
It's important to make sure you're feeling better, but it also makes sure that you don't get anybody else sick when you go back to work.