When the cold or flu virus strikes:

* Go to bed. Your body needs rest to fight the invading virus.

* Drink a lot of liquids, especially those of citrus fruits. Although tests do not confirm the usefulness of massive doses of Vitamin C, the body does seem to use more when it is battling a virus.

* Aspirin or aceteminophen may help lessen aches and pains and lower fevers in adults. Neither should be given to children or teen-agers with chicken pox or flu. Aspirin appears to be a link in the causation of Reye's syndrome. Acetominophen can affect the liver which is also dangerously affected in Reye's. Check with a pediatrician immediately if vomiting or behavioral changes occur in a child recovering from flu or chicken pox.

* Chicken soup does seem to help; it is nourishing, hot and wet, all things your body craves when you're sick.

* Check with your doctor if you run a fever more than two days, or if it is higher than usual.

* A vaporizer is useful for chest congestion, but keep it away from tiny hands.

* Stop smoking, whether to protect your own small airways or your child's. Children with smoking parents are more vulnerable to bronchial illnesses and take longer to recover.