If you use public transportation, I have good news: Taking trains and buses does not raise your risk for catching a cold or the flu, even if you’re getting coughed and sneezed on left and right. 

In fact, a new survey by the London School of Hygiene and Tropical Medicine has found that commuters who use public transportation actually get sick less often than people who drive to work. And it’s because they’re getting sneezed on. 
According to infectious disease expert Dr. Alma Adler, constant exposure to new germs, actually makes commuters less susceptible to illness because the more germs you’re exposed to, the stronger and better your immune system is. 
So if your cramped commute isn’t the cause of your sniffles, what is? Your kids. When researchers tracked the infection rates of nearly 6,000 people, they found that the adults almost always got their symptoms between three and seven days after their children got sick.