Princess Mary of Denmark Apologizes for Forgetting Coronavirus Precautions and Shaking Hands

Ole Jensen/Getty Princess Mary

Crown Princess Mary of Denmark is apologizing for her "mistake."

The 48-year-old royal visited the Grenaa sea aquarium on Wednesday, marking her first royal engagement since the summer holidays.

Upon her arrival, Mary shook hands with one of her hosts for the day, going against the Danish National Board of Health guidelines amid the COVID-19 outbreak. The following day, Princess Mary expressed her regret on Instagram.

"On land, at sea and in the air — we have to get used to wearing a mask. It is important that we all follow the health authorities' recommendations together," she captioned two photos of herself wearing face masks, translated from Danish.

"Yesterday I was in Grenaa for my first official visit after the summer holidays," she continued. "At sea and in the air it went fine, but on land I made a mistake and I unfortunately shook hands. It reminded me how important it is that we help each other live up to the recommendations. Stay safe and take care of each other."

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Princess Mary's visit to the aquarium came as she was appointed as President for the World Wildlife Foundation. During the outing, she helped release 50 sea rays to the wild, even kneeling down on a dock to hold five thornback rays in a net.

"The release of the sea stingrays must create new knowledge for both researchers and fishermen, as the majority of the 13 Danish stingrays today are threatened with extinction," according to an Instagram post about the engagement.

HENNING BAGGER/Ritzau Scanpix/AFP via Getty Princess Mary

Ole Jensen/Getty Princess Mary

The Australia native's family was directly affected by the COVID-19 outbreak. Mary and Prince Frederik's four children had to cut short their study abroad experience at Lemania-Verbier International School in Switzerland, returning to Denmark weeks early.

Ole Jensen/Getty Crown Prince Frederik and Crown Princess Mary with their children

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Mary's brother-in-law, Prince Joachim, is recovering at home after undergoing brain surgery on July 24. Prince Frederik paid his brother a visit last week, posing together for an outdoor photo.

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Prince Joachim is expected to make a full recovery.