Answer:
You have just as much of a chance catching a cold barefoot than with shoes on; however, the body is more prone to catch a virus the colder it is, so I guess it just depends on the weather you're in.
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That second part of the answer above is a common misunderstanding. You are not more prone to catch a virus the colder it is...that would mean that all or many more people in Alaska and Siberia are always sick with a cold or flu virus. There are some studies that found that people with "hypothermia" have a less active immune system...but just being cold is not hypothermia, there is a very big difference.