Glam revellers have proudly shown off their vaccine passports as they glammed up for a night on the town on the first day of fresh Covid restrictions in Newcastle, United Kingdom on December 15, 2021. Brits donning festive gear decided to tear up nightclub dance floors and booze in pubs despite fears over the Omicron variant. (Photo by Newcastle New Projects)

A resident receives a dose of Pfizer BioNTech COVID-19 vaccine at a rural village on December 01, 2021 in Aringay, La Union province, Philippines. The Philippines is rushing to vaccinate its population as it mulls making COVID-19 vaccination mandatory and amid the looming threat of the Omicron variant of the coronavirus. The country, which has just approved booster shots for its adult population, launched a three-day national vaccination holiday on November 29 to December 1 with the goal of vaccinating at least nine million additional people. (Photo by Ezra Acayan/Getty Images)

Two cats watch a mouse walking on the pavement in Kuwait City on March 8,2017. (Photo by Yasser Al-Zayyat/AFP Photo)

Couples take part in a competition during a mass wedding of 64 doctoral student couples at Harbin Institute of Technology, a university in Harbin, Heilongjiang province, China, June 4, 2017. (Photo by Reuters/Stringer)

An Iranian Shiite Muslim prays in Laylat al-Qadr, or the night of destiny, during holy fasting month of Ramadan after midnight, in central Tehran, Iran, early Sunday, June 18, 2017. Laylat al-Qadr is the night when Muslims believe the Quran was first revealed to prophet Muhammad. Worshipers gather in religious ceremonies to pray, ask forgiveness and make wishes on one of the most important nights of the Islamic calendar. Shiite Muslims, the vast majority of Iranians, believe the night happens either on 19th, 21st or 23rd of the holy month of Ramadan. (Photo by Ebrahim Noroozi/AP Photo)

A woman prays as she touches the carcass of a male elephant after he, according to forest officials, was electrocuted early morning in a paddy field on the outskirts of Guwahati, India, June 20, 2017. (Photo by Anuwar Hazarika/Reuters)

Jackie Barajas of Chula Vista dressed as Loki at Comic-Con in San Diego, USA on July 22, 2017. (Photo by K.C. Alfred/San Diego Union-Tribune via ZUMA Press/Rex Features/Shutterstock)

Convicted murderer Hector Alvarado Mazariegos, right, drops to the ground as he is hit by bullets of a Guatemala firing squad in the public cemetery at Mazatenango, June 28, 1975. His companion, Rocael Ortiz, met the same fate a few seconds later. Both were convicted of murder. (Photo by AP Photo/Anzueto)