Medical residents, who removed their clothes to protest against working conditions, take part on a protest during a strike in Barcelona, Spain, Tuesday, October 20, 2020. Regional authorities across Spain continue to tighten restrictions against a sharp resurgence of coronavirus infections that is bringing the country’s cumulative caseload close to one million infections, the highest tally in western Europe. (Photo by Emilio Morenatti/AP Photo)

A migrant worker wearing face masks to help curb the spread of the coronavirus walks up to a pedestrian bridge in Beijing, Sunday, December 6, 2020. Provincial governments across China are placing orders for experimental, domestically made coronavirus vaccines, though health officials have yet to say how well they work or how they may reach the country's 1.4 billion people. (Photo by Andy Wong/AP Photo)

A woman wears a face mask on her chin and walks past a cake depicting the coronavirus on display at the annual cake show organized as part of new year celebrations in Bengaluru, India, Tuesday, December 29, 2020. India's confirmed coronavirus cases have crossed 10 million with new infections dipping to their lowest levels in three months, as the country prepares for a massive COVID-19 vaccination in the new year. (Photo by Aijaz Rahi/AP Photo)

A Rohingya Muslim girl, Saira Begum carries food items distributed in aid as she walks towards her shelter in Taiy Khali refugee camp, Bangladesh, Tuesday, September 19, 2017. With a mass exodus of Rohingya Muslims sparking accusations of ethnic cleansing from the United Nations and others, Myanmar leader Aung San Suu Kyi on Tuesday said her country does not fear international scrutiny and invited diplomats to see some areas for themselves. (Photo by Dar Yasin/AP Photo)

A protester wearing improvised protective headgear walks away from a cloud of tear gas on July 18, 2021 in Bangkok, Thailand. Student protesters called for a demonstration demanding the resignation of Thailand Prime Minister Prayuth Chan-o-Cha, despite a ban on gatherings because of the country's current Covid-19 outbreak, and folded a demand for better action in combating the virus into their demands. (Photo by Sirachai Arunrugstichai/Getty Images)

A three-day-old Bengal tiger calf is cared for after being fed at the National Zoo in Masaya on August 30, 2021. A female Bengal tiger calf was born in the National Zoo of Nicaragua, the fourth of this species in risk of extinction born in captivity in the country, and is under special care due to a limited breastfeeding capacity of the mother. (Photo by Inti Ocon/AFP Photo)

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)

A 180 degrees rotated photograph shows the shadows of Polina (L), a six-year-old Belarusian first grade school girl, and her father, cast on the street while on their way to Polina's first day of school, which marks the traditional start of the academic year, in Minsk, Belarus, 02 September 2019. The start of a new academic year in Belarus, officially called Day of Knowledge, is a festive day for all school and university students in the country. (Photo by Tatyana Zenkovich/EPA/EFE)