A pedestrian wearing a face mask to protect against coronavirus, walks in front of a mural, at a metro station in Athens, Greece, Monday, November 15, 2021. Authorities say the rate of death related to COVID-19 in Greece has reached its highest level in six months as roughly one-third of the country's population remains unvaccinated. (Photo by Thanassis Stavrakis/AP Photo)

An affected boy walks along a muddy street after heavy rain in Nowshera district of Khyber Pakhtunkhwa, Pakistan, Friday, September 2, 2022. Planes carrying fresh supplies are surging across a humanitarian air bridge to flood-ravaged Pakistan as the death toll surged past 1,200, officials said Friday, with families and children at special risk of disease and homelessness. (Photo by Mohammad Sajjad/AP Photo)

A young girl walks with a Ukrainian flag during an event for Ukrainian Independence Day in the historical Grand Place of Brussels, Wednesday, August 24, 2022. European leaders are pledging unwavering support for Ukraine as the war-torn country marks its Independence Day. The commemorations Wednesday coincide with the six-month milestone of Russia's invasion. (Photo by Virginia Mayo/AP Photo)

An aerial view taken with a drone shows people walking past dried lava (L) from a previous volcanic eruption as they make their way to a location closer to watch the fresh volcano eruption near Grindavik, Reykjanes, Iceland, 17 July 2025. According to the Icelandic Meteorological Office, a magma flow has begun at the Sundhnuk crater range on 16 July. (Photo by Jakob Vegerfors/EPA)

Spot, a robot with dog-like movements, walks past a dog in Cathedral Square in Erfurt, Germany on April 20, 2021. Security service provider Ciborius, a provider of robotic security solutions with artificial intelligence, presented its artificial employee with high-resolution 360-degree all-round camera, ultra-bright LED light and a light detection system on Domplatz. (Photo by Michael Reichel/dpa)

In this February 2, 2015 photo, tourists jump as they pose for a picture, after disembarking from the Ocean Nova cruise ship, on King George Island, Antarctica. This tourist season, which runs November through March, more than 37,000 visitors are expected to walk on the coldest continent on Earth, about 10 percent more than the year before. (Photo by Natacha Pisarenko/AP Photo)

In this Tuesday, March 31, 2015 photo, Indian women walk carrying firewood they collected from a forest at Gobhali village on the outskirts of Gauhati, India. Every evening, hundreds of millions of Indian women hover over crude stoves making dinner for their families. They feed the flames with polluting fuels like kerosene or cow dung, and breathe the acrid smoke wafting from the fires. (Photo by Anupam Nath/AP Photo)

People who live in nearby villages make their yearly pilgrimage as they walk up the slopes of the Popocatepetl volcano in Mexico, Wednesday, March 12, 2014. Every year on March 12, residents make their way up the volcano celebrate the day of Don Gregorio Chino Popocatepetl, as the volcano is known to them, with food, music, dance and fireworks. When the sun rises, hundreds of pilgrims head out from the towns of Santiago Xalintzintla, Tlamacas and San Nicolas de Los Ranchos in van and trucks to drive, then walk up the 17,886-foot (5,450-meter) volcano for their daylong celebration. (Photo by Eduardo Verdugo/AP Photo)