By Dr. Brian McDonough

PHILADELPHIA (CBS) - You’ve heard warnings about heat stroke, sunburn, and heat exhaustion. But there may be another life-threatening danger brought on by the heat wave.

We know of many health problems, obviously heat stroke. People who are at high risk include the very old and the very young. But there is new information about another concern you might not be thinking about – swimming fatalities.

Swimming fatalities are up in many parts of the country. More people are going to areas where they can go swimming and many people who don’t know how to swim are deciding to take the chance because it’s too hot. This is particularly risky.

Obviously you want to cool off, but if you’re someone who doesn’t swim and is not used to swimming or is not a strong swimmer, you have to know about your environment and be careful.