Most people do not worry too much about minor cuts and scrapes or coming down with the sniffles, but for patients undergoing cancer treatments those can be dangerous situations.

Richard Thornhill says he never washed his hands so much or even cared about sanitation until he began his treatment for cancer.

Since his immune system has been weakened by chemotherapy, anything that might have a germ could be a threat to Thornhill and the progress of his treatments.

"You come back and you immediately sanitize your hands or wash your hands," he said.

"I mean, I washed my hands to the point where I've got just about (rubbed) all of the hair off of them."

And it's not just what he touches that can be a threat -- it can also be what he breathes.

Pollen or fungus in the air can cause respiratory infections this time of year -- and insects can be much more than just a nuisance.

In fact, any exposure to any microbes that might not be harmful to someone with a normal immune system can be very harmful to someone who is undergoing chemotherapy.

Any fever in a chemotherapy patient is regarded as an emergency and they should contact their physician right away.

Depending on the type of chemotherapy, it can be weeks or months before the immune system recovers as the bone marrow works to replenish cells.

Besides frequent hand washing, other strategies for chemotherapy patients include:

-Staying away from crowds, using the stairs to avoid crowded elevators and drinking bottled water.

-Women are more vulnerable to getting sick during the second half of their menstrual cycle, so they should be especially vigilant during this time.

-Avoid anything that makes cuts in your skin -- no matter how small, you might consider switching to an electric shaver rather than using a razor. Always wear gloves when gardening.

-Use toothbrushes with soft bristles and floss gently.

"If friends or family feel ill at all, even with a simple upper respiratory tract infection, try to avoid contact with the patient or if you must, you should wear a mask and be to sure to wash their hands vigilantly," says James Cancer Hospital oncologist Dr. Jeremy Young.

Otherwise, you may be putting a loved one at risk and jeopardize all they've done to battle and beat cancer.

With a report from CTV British Columbia's Dr. Rhonda Low