Revellers in Leeds, United Kingdom were excited to be out and about again on July 18, 2021. At a minute past midnight, England dropped most of its remaining Covid-19 social restrictions, such as those requiring indoor mask-wearing and limits on group gatherings. These changes come despite rising infections, pitting the country's vaccination programme against the virus's more contagious Delta variant. (Photo by Ioannis Alexopoulos/PA Wire Press Association via Getty Images)

An indigenous man of Mahmeri tribe wearing a costume of Puteri Gunung Ledang character receives a dose of the vaccine against Covid-19 in Banting, near Kuala Lumpur, Malaysia,15 August 2021. Malaysia recorded another 20,670 new Covid-19 cases on 14 August, bringing the cumulative total to 1,384,353 cases. (Photo by Ahmad Yusni/EPA/EFE)

Morenada dancers dance at the Plaza de Armas during the celebrations of the Morenada National Day in La Paz, Bolivia on September 7, 2021. (Photo by Manuel Claure/Reuters)

A woman fills her ballot paper during the State Duma, the Lower House of the Russian Parliament and local parliaments elections at a polling station in St. Petersburg, Russia, Friday, September 17, 2021. (Photo by Dmitri Lovetsky/AP Photo)

British singer and songwriter Ella McMahon, better known by her stage name Ella Eyre performs on stage at SWG3 on October 20, 2021 in Glasgow, Scotland. (Photo by Roberto Ricciuti/Redferns)

A Yemeni pro-government fighter is pictured during fighting with Huthi rebels on the south frontline of Marib, the last remaining government stronghold in northern Yemen, on November 10, 2021. A Yemeni military official said that 28 fighters from the pro-government Obaida tribe and seven government forces were killed in clashes with rebels south of Marib over the previous 24 hours. (Photo by AFP Photo/Stringer)

British Prime Minister Boris Johnson visits the Pavegen stand, a company that converts footsteps into energy, at the Innovation Zone during the UK-Africa Investment Summit in London, Britain on January 20, 2020. (Photo by Leon Neal/Pool via Reuters)

Participants perform parade in the street during Grebeg Sudiro festival on January 19, 2020 in Solo City, Central Java, Indonesia. Grebeg Sudiro festival is held as a prelude to the Chinese New Year, which falls on January 25th this year, welcoming the Year of the Rat. People bring offerings known as gunungan, including Chinese sweetcakes piled up into the shape of mountains, which are paraded in the streets followed by Chinese and Javanese performers. (Photo by Ulet Ifansasti/Getty Images)