Is Everyone On The Campaign Trail Getting Sick?

Health experts are weighing in on how the candidates can stay healthy.

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." 

Read: After Attack By Romney, Trump Boasts About His Products During Victory Speech

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.

Read: Hillary Clinton Barks Like a Dog and the Internet Goes Wild

Cruz was feeling so under the weather, he had to cancel events last weekend.

Saturday Night Live made mischief when Larry David, who was playing Bernie Sanders, refused to shake hands with a supporter.

Watch: Why Does Hillary Clinton Keep Having Coughing Fits?