What can the candidates do to stay healthy on the campaign trail?
ABC Chief Health and Medical Correspondent Dr. Richard Besser told IE: "They are constantly meeting people. They are shaking hands, touching people, all of the time. If you think about how cold and flu are transmitted, that is the perfect way."
Some days it seems that just about everyone running for president is feeling under the weather.
Besser said: "My advice, if you are stick stay home. Wash your hands. Use an alcohol sanitizer and get enough sleep. I know that the candidates can't do any of those things."
Remember Hillary Clinton’s epic coughing fit?
Marco Rubio struggled with a strained voice recently.
At the end of last Thursday’s debate, Ted Cruz extended his hand but Rubio didn’t want to shake it. People thought he was being rude but that wasn't the case.
“Marco is sick," his campaign tweeted. "That's why he didn't shake the other candidates’ hands after the debate.
Cruz was feeling so under the weather, he had to cancel events last weekend.