Yes, there are lots of studies on how the cold or flu is transmitted, and what can makes people susceptible. This is one example in which weather data is compared to respiratory infection visits at a children’s hospital in Mainz, Germany. The conclusion is that rhinovirus (primary cause of “colds”) is correlated to relative humidity and influenza A (a flu virus) is correlated with cold temperatures. They looked at a bunch of other respiratory infection viruses, too. Combining that with data from other studies such as this one in guinea pigs (a common model for respiratory infection studies) which suggests that aerosol virus spread is easier in low humidity, suggests that the weather and environmental conditions do a play a part in the spread of respiratory viruses.
Searching on Google Scholar should bring up lots of references.
The answer to the OP seems to be that it isn’t the individual being cold (because of not wearing warm clothing) which causes on increase in colds, but rather the cold weather and low humidity which favor the viruses, making the viruses more abundant and easier to catch. So putting on a warm coat isn’t going to do a thing to change the temperature.
You’re best bet to prevent colds is to frequently wash your hands (senior center, child care centers, elementary schools). And IT workers, remember to always wash your hands after touching somebody’s keyboard, those things are disgusting.
I have a memory which I haven’t tracked down (I’m at work), that what flu correlates to most is the bird migration schedules - apparently they carry the virus around the world as they migrate - when they leave the north in the winter and fly south, for example, the south gets more flu.
Note: Can’t remember if it was a specific kind of bird or the details - it was in a science magazine some years back, is all I remember.
I’m not aware of any studies, but since middle school (I grew up in Ohio), I have taken my morning shower, dressed, and walked out the door with wet hair. Okay, there were probably a few years there in high school when I actually did my hair in the mornings. But since college, definitely not.
So my own personal 20-year study: there is no causation.
My secretary at my old job was very old school and she would scold me every morning. “You should dry your hair! You’re gonna get the flu!”
One day, I whipped around on her and said, “J. We have worked together for five years. Have you known me to get sick, ever?”
“Well… no.”
“That’s because colds and flu are caused by viruses, not from catching a chill. You wanna not get sick? Wash your hands more. My wet hair has fuck all to do with anything except the fact that I prefer sleeping to fussing with my hair.”
Yep. Strange thing is, soon after that thread had run its course, I aired my apartment out, only to come down with something soon after. I know I know, I must have caught a virus from someone in the previous 24 hours, but that kind of thing makes it easy to understand why people come up with such nonsensical theories.