This time of year the common cold germs of Rhinovirus and Coronavirus and the dreaded Influenza, known as the flu, seem to come looking for you.
Researchers say those germs actually toughen up in cooler temps, but you have to be in contact with them to get sick.
The cold sends many of us inside, where we're surrounded by co-workers, classmates, family or friends who may be coughing and sneezing and spreading germs.
The heat we seek inside provides for dry air that allows those viruses to live and linger longer on surfaces such as door knobs.
You then come in contact with it and then touch your eyes, nose, or mouth and get infected.
Or someone sneezes or coughs in your direction, and the aerosol gets into your system for the same effect.
That's why it's so important that you routinely wash your hands.
If your sniffles and sneezes last longer than ten days and seem to respond to antihistamines, chances are it's not a cold, but your winter allergies making you miserable. You might want make an appointment with your doctor or allergist for relief.
For those with chronic illnesses, such as diabetes or heart disease, prolonged exposure to cold may weaken the immune system and make them more susceptible to infection if exposed.