Is sickness always due to a virus?

[Frog253]

My DS was sick again on Sunday (in back of MIL's car of all places), he must manage a pukey episode about 3 times a year and has done for as long as I can remember (he's 6).

Now sometimes we all get it and sometimes we don't. This time I called it a DS1 classic ie he woke feeling OK, ate his breakfast OK, started feeling ill and sleepy around 10am and finally threw up at midday-ish. He was only sick the once and was pretty keen to eat and drink soon afterwards, we starved him for 24 hours and kept him off school.

What puzzles me is where does this come from? How can I tell if we are all going to get it? How can I stop it? I do try and get the children to wash their hands lots but nothing seems to stop the seemingly endless round of sickness. SO far no one else has had it but am not sure we are out of the sickness woods yet. I have three DCs btw. Am pretty sure DS1 is not sick because of emotional things. Any thoughts appreciated.

my kids get pukey about that many times a year. I would say its fairly normal, and they pick it up in school, little kids dont ever wash there hands like we would. I go into total melt down everytime it happens.

I was never as ill as often as this as a child and my sister and parents never seemed to catch it from me. I seem to catch these things more as an adult than as a child.

Also DS1 was ill after a week of no contact with any other children. Could something else have made him ill.