A little girl holding her newborn sister waits for their turn in a queue during a vaccination campaign under the supervision of the Syrian Arab Red Crescent (SARC) humanitarian nonprofit organization, in the besieged Syrian town of Douma, Syria, 23 May 2017. According to a statement from SARC, in the city of Douma some 12,809 children under the age of five were immunized in a vaccination campaign to prevent measles and poliomyelitis. The campaign was the first of its kind with the participation of 100 volunteers. SARC has been delivering vaccines to 17 health centers approved for vaccination campaigns in towns and villages in the Eastern Ghouta area. (Photo by Mohammed Badra/EPA)

A woman plays around as she walks across a glass-bottomed suspension bridge in a scenic zone in Pingjiang county in southern China's Hunan province Thursday, September 24, 2015. The bridge, 300 meters (984 feet) long and 180 meters (590 feet), opened to visitors on Thursday for the first time since its conversion from a regular suspension bridge was completed. (Photo by Chinatopix Via AP Photo)

Teacher Mahajera Armani and her class of girls pose for a picture at their study open area, founded by Bangladesh Rural Advancement Committee (BRAC), outside Jalalabad city, Afghanistan September 19, 2015. (Photo by Reuters/Parwiz)

Graffiti is painted on the bathroom walls at a restaurant in the Williamsburg area of Brooklyn borough in New York, United States, October 1, 2015. Some 2.4 billion people around the world don't have access to decent sanitation and more than a billion are forced to defecate in the open, risking disease and other dangers, according to the United Nations. To mark World Toilet Day on November 19, Reuters photographers captured pictures of toilets in cities, towns and villages around the globe. (Photo by Shannon Stapleton/Reuters)

Members of ASC Tornados, the motorcycle display team of the Indian army, lie in a row on the ground as another performs a stunt by jumping over them during the 225th anniversary celebrations of Army Service Corps in Bangalore, India, Tuesday, December 8, 2015. The Army Service Corps which was established in 1790 is an arm of the Indian Army which handles its logistic support function. (Photo by Aijaz Rahi/AP Photo)

Hundreds of Nigerians celebrate at an intersection in the flashpoint northern city of Kaduna on March 31, 2015 the victory of main opposition All Progressives Congress (APC) presidential candidate Mohammadu Buhari. (Photo by Nichole Sobecki/AFP Photo)

A one month old Turquoise colored Green Veiled Chameleon perches on a finger in the Cardin's Chameleons boothat Repticon 2014 Sunday, August 3, 2014 in Jacksonville, Fla. The vendor specializes in captive bred and born Veiled Chameleons and this particular specimen cost $40.00. The Repticon reptile and Exotic Animal show made its stop in Jacksonville over Saturday and Sunday offering a variety of cold blooded critters and related supplies for sale at the University Center on the University of North Florida campus. The show, which travels nationally stops in Jacksonville several times a year according to event vendor team leader Patty Healey. (Photo by Bob Self/AP Photo/The Florida Times-Union)

A South Sudanese model applies make-up during the Festival of Fashion and Arts for Peace in Juba August 9, 2014. (Photo by Andreea Campeanu/Reuters)