Higher gas prices are driving more people to take public transportation -- and as a result could drive up the number of cold and flu cases this season.
The American Public Transportation Association announced that in the second quarter of 2008, more Americans opted to ride public buses and trains rather than take their own cars -- 140 million more trips than the same time last year.
However, as more and more commuters pack into trains and buses, the chances that they will be placed in close proximity to someone who is already infected with a cold or flu virus are significantly higher.
So what can we do as passengers to avoid the cold and flu, otherwise known as the "crowding disease"?
We have all been in this situation before: The person you're sitting next to is constantly coughing and sneezing. It is pretty obvious that they are sick, and you start to get that creepy sensation as if some of their illness has seeped into your system. How does one escape from this scenario to avoid getting sick?
"Get somewhere and sit somewhere else," advises Dr. Howard Markel, professor of the history of medicine and of pediatrics and communicable diseases at the University of Michigan Medical School. "If someone is coughing, I would avail myself that opportunity. Our mothers were right when they said, 'Don't let anyone cough on you.'"
More often than not, however, trains and buses are so packed that it's difficult to remove yourself from such situations. So, what do you do when you find yourself trapped?
"Breathe shallowly," Markel recommends. "Try not to let them cough on you." In that way, he explains, transmission of germs can be reduced.
If you are seated next to a child who is hacking up a storm, you should get up even faster.
"Children do not have good respiratory etiquette," says Markel. One might say that this is an understatement; children have the tendency to drool, and mostly do not cover their mouths when sneezing or coughing.
In addition to this, once adults have children, they double their risk of getting the cold and flu, according to Charles Gerba, professor of environmental microbiology at the University of Arizona. And children tend to touch themselves with their hands about 40 times per hour, about twice as often as adults do.
Also, washing your hands after you get off the subway or train is probably a good idea. Good old soap and water can eliminate any of the germs you may have collected while riding alongside someone with the cold or flu.
There is little evidence to suggest that some surfaces on public transportation are germier than others. According to Gerba, there haven't been many studies done on germs and public transportation.
However, there are some facts to keep in mind.
The metal poles and straps that passengers hold on to are often contaminated with microbes and bacteria.
"Stainless steel is a good transfer surface," Gerba points out, adding that about 50 percent of the germs on those poles are picked up by human hands, making them great carriers of the cold and flu virus.
You can also try and be aware of your surroundings and scope out where people are sitting. That way, you can possibly reduce your exposure to the virus.
"Go to the least used part of the bus," Gerba suggests. "The back of the bus seems like the least used part."