If a person is exposed to flu virus, can he drink prune juice and eat beans to "flush" his system to avoid getting sick?

This will not work.: Nothing other than frequent and vigorous handwashing will decrease your chances of getting the flu. If you do, see your doctor promptly, since there is medication to decrease the duration and severity of the illness, if taken promptly.

Myths: No foods will postpone or interfere with a viral illness after exposure. Thus this myth, that prune juice or beans will 'flush' the symptom is a false myth with no truth to it.

Flu: Is a self limiting viral disease that can have complications. Healthy people with good immune system get over it without sequelae but the old and the young can have bad complications. Rest, and fluids to avoid dehydration is what is recommended. Don't eat things that can cause diarrhea but fluids is needed. You can't flush your system, your system maintains its own balance.