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)

Ivanelis Jimenez, front, and Veronica Barreto pose for the camera wearing Puerto Rican flag dresses as they welcome passengers exiting Carnival's Mardi Gras cruise ship, docked in the bay of San Juan, Puerto Rico, Tuesday, August 3, 2021, marking the first time a cruise ship visits the U.S. territory since the COVID-19 pandemic began. (Photo by Carlos Giusti/AP Photo)

A woman cools off at a fountain in central Cordoba, southern Spain, 11 August 2021. Andalucia was put on orange alert for high temperatures, with a new heatwave forecast to reach temperatures of over 41 degrees Celsius in the region. (Photo by Salas/EPA/EFE)

A lemur inspects a camera at Tarsus Nature Park in Mersin, Turkey on July 25, 2021. The population of lemurs, one of the inhabitants of Tarsus Nature Park, increases with new births every year. Lemurs are among the most interesting species in the zoo. (Photo by Serkan Avci/Anadolu Agency via Getty Images)

Models pose during the Paul Costelloe Presentation during London Fashion Week September 2021 on September 17, 2021 in London, England. (Photo by Matt Crossick/Empics Entertainment/Getty Images)

A masked dancer performs as part of “Devi Pyankha” (Devi Dance) to mark the beginning of the Indra Jatra Festival in Kathmandu, Nepal on September 15, 2021. Nepali celebrate the Indra Jatra festival to worship “Indra”, the god of rain and to mark the end of monsoon season. (Photo by Sunil Sharma/ZUMA Press Wire/Rex Features/Shutterstock)

Dinosaur mockups are installed in Danghangpo, Goseong, some 466km southeast of Seoul, South Korea, 06 September 2021, 25 days ahead of the Gyeongnam Goseong Dinosaur World Expo 2021 set for 01 October until 07 November. Goseong is one of the world's three largest fossilized dinosaur footprint sites, along with Colorado in the United States and the west coast of Argentina. (Photo by Yonhap/EPA/EFE)

Bicycle rickshaw drivers chat as they wait for customers near the Drum Tower in a traditional neighbourhood on September 30, 2021 in Beijing, China. China will mark National Day and the Golden Week holiday from October 1st. (Photo by Kevin Frayer/Getty Images)