Trump is reportedly such a germaphobe that aides aren't allowed to cough in his presence and visitors must wash their hands before entering the Oval Office

NICHOLAS KAMM/AFP/Getty Images

US President Donald Trump shakes hands with supporters as he arrives for a campaign rally at Southport High School in Indianapolis, Indiana, on November 2, 2018.

• Aides to President Trump have told Politico that he hates it when staff cough or sneeze in his presence because of his longstanding germaphobia.
• Trump also reportedly asks visitors to wash their hands in a bathroom off the Oval Office, and uses hand sanitizer after shaking hands at campaign events.
• In an interview, Trump described shaking hands as "barbaric" because it spreads germs.
• In June, Trump ordered acting chief of staff Mick Mulvaney from his office after he coughed during a TV interview.
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President Donald Trump is such a germaphobe that he asks visitors to the Oval Office to wash their hands before entering the room, and will "scowl" at staff for coughing or sneezing in his presence, according to a report from Politico.

"If you're the perpetrator of a cough or of a sneeze or any kind of thing that makes you look sick, you get that look," a former Trump campaign official told the publication.

"You get the scowl. You get the response of - he'll put a hand up in a gesture of, you should be backing away from him, you should be more considerate and you should extricate yourself from the situation."

According to the report, so keen is the president to avoid contact with germs, that he will ask visitors to wash their hands in a bathroom off the Oval Office before entering the room.

Read more: In hour-long Fourth of July speech, Trump mistakenly claims US soldiers 'seized airports' during the Revolutionary War

Ron Sachs/Pool/Getty Images

President Donald Trump signs a National Manufacturing Day Proclamation in the Oval Office of the White House on October 6, 2017.

As soon as he is done shaking hands with members of the public at campaign events will ask a personal aide for hand disinfectant when he steps back into his car.

Flights on board the confined spaces of Air Force One reportedly present a particular problem, with aides who have colds acting on the understanding that they must stay away from Trump.

The president once even ordered the White House physician to inspect former press secretary Anthony Scaramucci after he coughed on a flight to Ohio, Politico reported.

Read more: Trump kicked his acting chief of staff out of the Oval Office for coughing during a TV interview

Trump's germaphobia has long been known, and was plain to see in June when he interrupted an interview with ABC's George Stephanopoulos to order coughing Acting Chief of Staff Mick Mulvaney from the room.

"I don't like that, you know. I don't like that. If you're going to cough, please, leave the room," said a visibly irate president.

His public disdain for germs was evident in a 1999 interview when he called shaking hands a "barbaric practise," because it spreads flu germs.

Researchers in Denmark have even suggested that Trump's germaphobia may be linked to his hostility to mass immigration. They found that test subjects with a high degree of "disgust sensitivity" were more likely to be opposed to immigration.