A convoy of Syrian Red Crescent trucks arrives in Douma, in the Syrian rebel-held enclave of Eastern Ghouta, on Monday. This aid convoy is the first to reach the besieged area in weeks.
Amer Almohibany/AFP/Getty Images
Smallpox virus, colorized and magnified in this micrograph 42,000 times, is the real concern for biologists working on a cousin virus — horsepox. They're hoping to develop a better vaccine against smallpox, should that human scourge ever be used as a bioweapon.
Chris Bjornberg/Science Source
Workers spray to kill fleas in a public school in Antananarivo, Madagascar's capital. A bite from an infected flea can spread the plague, which has stricken 157 people in the island nation since August.
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A member of the Syrian government forces watches during an evacuation of Syrian rebel fighters and civilians from a opposition-held area of Aleppo on Friday.
George Ourfalia/AFP/Getty Images
One of these candidates will be the next head of WHO. Top row from left: Tedros Adhanom Ghebreyesus, Flavia Bustreo, David Nabarro. Bottom row from left: Miklós Szócska, Sania Nishtar, Philippe Douste-Blazy.
Getty Images, AP and WHO