A man takes a “selfie” with camels at a farm in Taif November 1, 2014. Saudi Arabia said late on Wednesday it had detected six new cases of the deadly Middle East Respiratory Syndrome (MERS) in 24 hours, the biggest daily jump for months with officials blaming lax hospital procedures. Scientists are not sure of the origin of the virus, but several studies have linked it to camels and some experts think it is being passed to humans through close physical contact or through the consumption of camel meat or camel milk. (Photo by Mohamed Alhwaity/Reuters)

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)

A giant river otter, the world's largest otter species, looks out of its enclosure at the newly completed River Safari in Singapore, on March 25, 2013. (Photo by Wong Maye-E/Associated Press)

A girl dances in front of the digital art installation “Light in Dark” created by teamLab, a collaborative of Japanese digital artists, during a special exhibition of “Shake! Art Exhibition! and Learn and Play! teamLab Future Park” at National Museum of Emerging Science and Innovation (or Miraikan) in Tokyo, Japan, 19 January 2015. The exhibition is held through 01 March 2015. (Photo by Kimimasa Mayama/EPA)

A man salts a downtown sidewalk in Washington, Thursday, March 5, 2015, as snow begins to fall. The U.S. federal government said its offices in the Washington area will be closed Thursday because of a new round of winter weather expected in the region. The Office of Personnel Management said non-emergency personnel in and around Washington were granted excused absences for the day. Emergency employees and telework-ready employees were expected to work. (AP Photo/Andrew Harnik)

Tourists take a “selfie” as demonstrators burn a trash container during a May Day rally in Barcelona, Spain, on May 1, 2014. Tens of thousands of workers marked May Day in European cities with a mix of anger and gloom over austerity measures imposed by leaders trying to contain the eurozone's intractable debt crisis. (Photo by Manu Fernandez/Associated Press)

Collided passenger train cars are seen in Taebaek, South Korea, Tuesday, July 22, 2014. Two passenger trains collided head-on in eastern South Korea on Tuesday afternoon, killing one passenger and injuring dozens, fire officials said. (Photo by AFP Photo/Yonhap)

A woman with “I'm Charlie” written on her hand takes part in a Hundreds of thousands of French citizens solidarity march (Marche Republicaine) in the streets of Paris January 11, 2015. French citizens will be joined by dozens of foreign leaders, among them Arab and Muslim representatives, in a march on Sunday in an unprecedented tribute to this week's victims following the shootings by gunmen at the offices of the satirical weekly newspaper Charlie Hebdo, the killing of a police woman in Montrouge, and the hostage taking at a kosher supermarket at the Porte de Vincennes. (Photo by Yves Herman/Reuters)