Chinese aids activists hand out condoms in a subway train in Wuhan, central China's Hubei province on December 1, 2014. The World Health Organization issued a call to action to China on December 1, 2014 over HIV/AIDS as government figures said nearly half a million people are living with the disease or its precursor, with hundreds of thousands more thought to be undiagnosed. (Photo by AFP Photo)

Hotel staff practice self-defence skills after a training session given by team member of Special Weapons and Tactics (SWAT) team, in Hangzhou, Zhejiang province, April 7, 2016. (Photo by Reuters/Stringer)

Hospitality staff members laugh as they stand on Tiananmen Square before the closing ceremony of China's 19th Party Congress at the Great Hall of the People in Beijing, Tuesday, October 24, 2017. The ruling Communist Party on Tuesday formally lifted Xi Jinping's status to China's most powerful ruler in decades, setting the stage for the authoritarian leader to tighten his grip over the country while pursuing an increasingly muscular foreign policy and military expansion. (Photo by Mark Schiefelbein/AP Photo)

A woman cries while sitting on a road amid the destroyed city of Natori, Miyagi Prefecture in northern Japan March 13, 2011, after a massive earthquake and tsunami. Five years on from the tsunami that triggered meltdowns at Japan's Fukushima nuclear plant, the page is anything but turned. A magnitude 9 earthquake and towering tsunami on March 11, 2011 killed nearly 16,000 people along Japan's northeastern coast and left more than 2,500 missing. The 10-metre (33-foot) tsunami swept away everything in its path, including houses, ships, cars and farm buildings. (Photo by Asahi Shimbun/Reuters)

Gertrude “Billie” Murphy, 22, is brought in for questioning in the murder case of Michael Stopec, who was shot and killed in an apartment hotel, circa July 1927. Murphy had been friends of the married Stopec and his suspected killer Henry Guardino, 31. It is said that Stopec and Guardino were “bitter rivals for the favor of Billie” and that Murphy had tired of Guardino and was going to stay with Stopec. Murphy was also married to a man in the Joliet penitentiary. (Photo by Chicago Herald & Examiner Historical Photo)

This combination of August 30, 2005 and July 29, 2015 aerial photos shows downtown New Orleans and the Superdome flooded by Hurricane Katrina and the same area a decade later. Katrina's powerful winds and driving rain bore down on Louisiana on August 29, 2005. The storm caused major damage to the Gulf Coast from Texas to central Florida while powering a storm surge that breached the system of levees that were built to protect New Orleans from flooding. (Photo by David J. Phillip/Gerald Herbert/AP Photo)

Ukrainians wearing traditional costumes sing Kolyadky or Ukrainian Christmas Carols, as a part of Orthodox Christmas in Kiev, Ukraine, Thursday, January 7 2016. Orthodox Christians mark their traditional Christmas Day Jan. 7, with many ancient symbolic events. (Photo by Sergei Chuzavkov/AP Photo)

A vendor carries her products in a bucket on her head as she walks through the neighborhood of Jalousie, in the commune of Petion Ville, Port-au-Prince, on December 17, 2018. On the hills of Port-au-Prince, a chaotic jumble of structures stretches ever farther into the distance: Haiti's capital is suffering under the weight of high inflation, endemic corruption and a perilous drop in the value of its currency. Jalousie is a poor neighborhood of the capital which lacks sanitation and potable water. (Photo by Hector Retamal/AFP Photo)