..hand, foot, and mouth disease

    Believe it or not, there is such a thing.  It's an infectious disease of children, usually under 5, that is characterized by a high fever and blisters on/in the hands, feet, and mouth.  It does not require any treatment and resolves without complications in 5-7 days.
    It is caused by the Coxsackie virus and, like most viral illnesses, is probably most contagious before symptoms develop.  Chicken pox, for instance, is most contagious during the several days of non-specific upper respiratory symptoms that precede its pathognomonic rash, and much less contagious once the rash develops.  Therefore, isolation of those both of these illnesses is probably unnecessary (minimally contagious by then) and ineffective (too late!).
    Several sites describe this illness further:

• article 1 - from Dr. Koop.com

• article 2 - click on the very nice pictures at the bottom for a bigger view

• article 3 - from CDC

    In closing, a few more thoughts about viral illnesses:

• A flu shot only prevents influenza, which is a particular kind of viral infection, primarily affecting the respiratory tract.  It does not prevent any other viral illnesses, including the common cold, hand/foot/mouth, chicken pox, polio, measles, hepatitis, etc.

• I have often been told by people, "when I was a kid, and the kid next door got chicken pox, my mother sent us all over to play with him so that we would get it, too, so we would all get it over with at the same time and when we were small".  While this seemed to work, it was probably unnecessary, since the illness had already been contracted in the several days before.  The incubation period is about 1-3 weeks, so it is difficult to know when the illness was actually contracted.