A Swiss Guard (R) who fell ill is helped as Pope Francis leads the weekly audience at the Paul VI hall at the Vatican January 13, 2016. REUTERS/Alessandro Bianchi 

A Swiss Guard who fell ill (R) is helped as Pope Francis leads the weekly audience at the Paul VI hall at the Vatican January 13, 2016. REUTERS/Alessandro Bianchi 

A Swiss Guard (R) who fell ill is helped as Pope Francis leads the weekly audience at the Paul VI hall at the Vatican January 13, 2016. REUTERS/Alessandro Bianchi 

EDITORIAL USE ONLY - NO COMMERCIAL OR BOOK SALES. Medics carry a seriously ill Syrian refugee child over Greece's border with Macedonia, near the Greek village of Idomeni, September 9, 2015. Most of the people flooding into Europe are fleeing violence and persecution in their home countries who have a legal right to seek asylum, the United Nations said on Tuesday. REUTERS/Yannis Behrakis 

EDITORIAL USE ONLY - NO COMMERCIAL OR BOOK SALES. Medics carry a seriously ill Syrian refugee child over Greece's border with Macedonia, near the Greek village of Idomeni, September 9, 2015. Most of the people flooding into Europe are fleeing violence and persecution in their home countries who have a legal right to seek asylum, the United Nations said on Tuesday. REUTERS/Yannis Behrakis TPX IMAGES OF THE DAY 

Yaw Myaw (L) applies a traditional healing method for fever using a sharp tin can on her mother Zawn Lum at a camp for internally displaced persons in the suburbs of Myitkyina, the capital of Kachin State July 7, 2013. Thousands fled when fighting erupted between Myanmar government troops and the Kachin Independence Army (KIA) after a ceasefire collapsed in June 2011. There are now at least 85,000 internally displaced persons in Kachin and neighboring Shan State, says the United Nations. REUTERS/Damir Sagolj (MYANMAR - Tags: SOCIETY CIVIL UNREST HEALTH) 

Zainab Batool, an 11-year-old girl with fever, rests her head on her mother's lap while waiting for a medical check-up at the Services Hospital in Lahore September 18, 2011. Cities across Pakistan launched a fumigation campaign to eliminate mosquitoes and control breeding to protect citizens from dengue fever. Dengue fever continued its unending spree as six more patients died of the fever in Lahore bringing the total number of deaths in Punjab to 37, local media reported. REUTERS/Mohsin Raza (PAKISTAN - Tags: HEALTH DISASTER) 

Sierra Leonean doctor Donald Samuel Grant (R), accompanied by U.S. medical student Vanessa Raabe, attends to a patient in the Lassa fever isolation ward at Kenema Goverment Hospital in southeastern Sierra Leone, February 7, 2011. Lassa fever, named after the Nigerian town where it was first identified in 1969, is among a U.S. list of "category A" diseases - deemed to have the potential for major public health impact - alongside anthrax and botulism. The disease is carried by a species of rodent, Mastomys Natalensis, found across sub-Saharan Africa and often eaten as a source of protein. It infects an estimated 300,000-500,000 people each year, and kills about 5,000. Picture taken February 7, 2011. To match Reuters-Feature BIOTERROR-AFRICA/ REUTERS/Simon Akam (SIERRA LEONE - Tags: HEALTH SOCIETY) 

Mariam Dagane, who is infected with Rift Valley Fever, rests on her bed at the Garissa hospital, 390 km (242 miles) north-east Nairobi, January 9, 2007. Rift Valley Fever, a highly contagious virus, has killed 74 people in Kenya and infected hundreds more after spreading from the northeastern region to the coast, the health ministry said on Tuesday. REUTERS/Radu Sigheti (KENYA) 

A security guard in an office building screens a visitor for fever in Taipei, December 18, 2003. A medical researcher in Taiwan has tested positive for SARS, the first case in Greater China since the flu-like virus killed hundreds of people and battered the region's economies this year. . REUTERS/Simon Kwong RC/DL 

ZAINAB SALAH, A 3 YEAR-OLD IRAQI GIRL SUFFERING FROM BLACK FEVER IS
COMFORTED BY HER MOTHER IN A CHILDREN'S HOSPITAL IN BAGHDAD.

Zainab Salah, a 3 year-old Iraqi girl suffering from black fever and whose
brother died from the same disease on Monday, is comforted by her mother in
a children's hospital in Baghdad May 27, 2003. Visceral leishmaniasis or
black fever, is a disease which is transmitted through the bite of the
sandfly, and affects 500, 000 people every year accordiing to the WHO, of
which 60,000 die. Pictures of the month May 2003 REUTERS/Damir Sagolj
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