As you take steps to avoid the germs and viruses that proliferate as winter progresses, you've no doubt received a good share of advice on how to avoid catching whatever's going around.
ABCNews OnCall+ spoke with experts about some of the popular myths about germs that tend to spread as fast as the bacteria themselves this time of year.
Is a dog's mouth cleaner than a person's? How unsafe are public toilet seats? Some of these questions lack hard data, and the study findings sometimes conflict.
So before taking advice from your friends, you might want to check their wisdom about our microbe neighbors.
Fact or Myth? You can get infections or illnesses from sitting directly on a public toilet seat.
"Just sort of sitting on the seat and having that contact with the skin on your butt isn't going to be a way of transmitting an infection, " said Elizabeth Scott, co-director and founder of the Simmons Center for Hygiene and Health in Home and Community Settings at Simmons College in Boston.
"I think that one's associated with the fact that we all find public toilets very disgusting, " she said, adding that you were more likely to get sick from touching the toilet seat or the flush handle with your hand.
Dr. J. Owen Hendley, professor of pediatric infectious disease at the University of Virginia Children's Hospital, said that this myth has been a persistent one.
Of getting an infection, he said, "I guess you could, but I've never known of a documented case where that actually happened."
But that has not stopped the myth. Hendley noted that the concern might have originated with a fear that syphilis could spread through toilet seats. He said that that fear is likely behind the design of many public toilet seats in which the seat itself is open in the front, preventing contact between the person and the seat in that area.
But the knowledge that sitting directly on the seat doesn't spread the germs doesn't seem likely to make it more appealing.
"It probably was true in the sense that inside of an aircraft cabin, if filled to capacity, you would have a lot of people breathing germs in and out, " said Sattar.
But, he said, "More recent aircraft design has created engineering controls which reduce that risk."
Sattar notes that HEPAs, or high efficiency particulate arresters, which were developed around World War II, trap tiny particles in the air so that any particle that might be carrying viruses or bacteria is caught when viruses pass through the air system in the aircraft.
So planes, like any crowded area, pose an increased disease risk, but it isn't clear how much, if any, of that is due to the recirculated air.
Sattar also noted that the World Health Organization will be examining this issue to ensure that passengers aren't sharing illnesses with their fellow travelers.