A four-legged robot dog called SPOT patrols a park as it undergoes testing to be deployed as a safe distancing ambassador, following the coronavirus disease (COVID-19) outbreak, in Singapore on May 8, 2020. (Photo by Edgar Su/Reuters)

A pedestrian wearing a form of PPE (personal protective equipment) of a perspex full-face covering, as a precautionary measure against COVID-19, walks across Oxford Street in central London on June 11, 2020, as non-essential shops prepare to re-open on June 15. Britain's current guidelines on social distancing remain at two metres (2M), but business leaders and some politicians are on Thursday calling for it to be reduced to one (1M), or one-and-a-half (1.5M) metres. (Photo by Justin Tallis/AFP Photo)

A face mask discarded in a forest in the Taunus region near Frankfurt, Germany, Sunday, October 18, 2020. (Photo by Michael Probst/AP Photo)

A man is arrested by Police during clashes in Rotterdam, The Netherlands, 25 January 2021. Police's mobile unit is present and has carried out charges to clear the street. Some arrests have also been made and a water cannon has been used. Nationwide protest against coronavirus restrictions and curfew imposed by Dutch government broke out during the weekend in many Dutch cities, leading to some violent riots and clashes with Police. (Photo by Marco de Swart/EPA/EFE)

Vietnamese dentist Tran Phuong Thao and her husband Tran Minh Hieu wearing protective masks, kiss at their wedding ceremony during the coronavirus disease (COVID-19) outbreak in Hanoi, Vietnam on January 28, 2021. (Photo by Kham via Reuters)

The Sea Life Trust team move Beluga Whale Little Gray from a tugboat during transfer to the bayside care pool where they will be acclimatised to the natural environment of their new home at the open water sanctuary in Klettsvik Bay in Iceland on August 7, 2020. The two Beluga whales, named Little Grey and Little White, are being moved to the world's first open-water whale sanctuary after travelling from an aquarium in China 6,000 miles away in June 2019. (Photo by Aaron Chown/PA Images via Getty Images)

Grumpy Cat attends the “Grumpy Cat: A Grumpy Book” Book Event at Bookends Bookstore on October 16, 2013 in Ridgewood, New Jersey. (Photo by Michael N. Todaro/WireImage)

Five-year-old sniffing dog “Vine” wears protection goggles against the sun and dust as he poses together with Giulia Gausemann for photographers, at the sniffing dogs school of the German Army (Bundeswehr) in Daun, Germany, July 24, 2020. The Bundeswehr sniffing dogs school and the veterinarian university of Hanover are developing a training programme to sniff out the coronavirus disease (COVID-19) with dogs at airports, border crossings and other highly frequented places. (Photo by Wolfgang Rattay/Reuters)