U.S. Presidential Candidate Hillary Clinton exits her daughter Chelsea Clinton's apartment at 21 E. 26th St. after attending an anniversary event at the World Trade Center 9/11 Memorial in Manhattan. (Photo by Yana Paskova/For The Washington Post)

Being a presidential candidate in 2016 fulfills the perfect formula for illness. Flying to multiple cities in a single day, exhausted from being on your feet for hours-long stretches giving speeches and mingling with voters, eating who knows how much salt and fat in takeout containers, shaking hands with thousands of germy constituents.

Hillary Clinton’s stumble over the weekend in New York as a result of what her aides described as “overheating” while recovering from pneumonia has set off a firestorm of concern about whether the 68-year-old Democratic nominee is fit enough to lead the country. Clinton has been particularly sensitive to attacks about her health because of her age, a concussion she suffered in 2012 and a lot of unsubstantiated talk among conservatives that she has been hiding a serious illness. These rumors have persisted even though her doctor has declared her perfectly healthy.

In the interest of putting Sunday’s incident into perspective, it’s important to point out that Clinton is far from the only politician — young or old — experiencing the health hazards of being on the road for months.

During the Republican primaries in March, Sen. Ted Cruz (Tex.) tookoff  a day and a half to recuperate. Mississippi state Sen. Chris McDaniel wrote on Facebook, “Ted Cruz will not be in Mississippi tomorrow, as he evidently does not feel well. This is difficult news to deliver, but we trust that God has a plan for the campaign and for Mississippi.” Sen. Marco Rubio (Fla.) awkwardly resorted to bumping fists and elbows after a Republican debate after coming down with something. A campaign volunteer, Garrett Ventry, made sure to clarify on Twitter that it wasn’t a snub.

In describing a Democratic debate, New York Times reporter Matt Flegenheimer wrote that both Clinton and her Democratic primary rival, Sen. Bernie Sanders (Vt.), “powered through moments of rasp.”

Clinton’s general-election rival, Republican Donald Trump, has tried to portray himself as more robust than the rest — but might his habits rather than his innate physical health have kept him well this season?

Trump, a known germophobe, has referred to shaking hands as “one of the curses of American society.”

“I happen to be a clean hands freak,” he wrote in his 1997 book “The Art of the Comeback.” “I feel much better after I thoroughly wash my hands, which I do as much as possible.”

While his aversion to the touchy-feely convention of campaigning has generated many a snarky comment about whether he has obsessive-compulsive disorder or some other mental health issue, Trump’s worries are not unreasonable.

A large number of yucky bacteria and viruses can be spread by hand-to-hand contact. These include flu germs, fecal matter that can give you the dreaded norovirus, and “superbugs” with no effective treatment.

One recent survey estimated that a third of Americans don’t wash their hands after using a public restroom and that 70 percent only rinse with water. Moreover, nearly 60 percent of people wash their hands for 15 seconds or less. The Centers for Disease Control and Prevention says that more than 20 seconds is required. The CDC notes that’s about the amount of time it takes to hum “Happy Birthday” twice. The World Health Organization says even that isn’t adequate and recommends a more elaborate method of hand-washing that takes 42 seconds.

It’s important to note that the 2015 survey was conducted by Bradley, a company that makes commercial hand-washing products. But the idea that most people are, uh, not so great at personal hygiene is supported by similar research over many years. A Michigan State University study published in the Journal of Environmental Health in 2013, for instance, found that only 5 percent of people washed their hands long enough to kill infection-causing stuff and that men were much worse at it than women. The study involved having a dozen students stationed at restrooms in bars, restaurants and other public establishments and logging what they saw into their smartphones.

Republican presidential candidate Donald Trump, left, and former Florida governor Jeb Bush talk after the CNN Republican presidential debate at the Ronald Reagan Presidential Library and Museum on Sept. 16, 2015, in Simi Valley, Calif. (Mark J. Terrill/AP)

But while there may be a scientific basis for Trump’s aversion to shaking hands, the flip side — as my colleague Amber Phillips pointed out last year — is that avoiding handshakes may not really be “compatible” with being president. “Part of a politician’s job description is to shake hands — lots of them. An estimated 65,000 a year if you’re president of the United States,” she wrote.

There are a few ways to get around this. Purell, for one. In a March 2003 article in the New Yorker, David Owen noted that George W. Bush used it after shaking hands with Barack Obama. “Bush was ahead of the curve: he also gave a squirt to Obama, and recommended it as a cold preventative,” Owen wrote.

Candidates may also want to consider high-fives and first bumps. A study published in the American Journal of Infection Control pointed out that these greetings can involve less skin-to-skin contact with the other person. High-fives appear to pass on only half as many germs as handshakes, on average, and fist bumps one-20th. Mathematically speaking, that means fewer chances of getting sick — and possibly a bump in public confidence about a politician’s health.

Read more:

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