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.
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A government worker sprays mosquito insecticide fog in Kuala Lumpur, Malaysia, earlier this month to block the spread of Zika. The U.S. CDC advises pregnant women to reconsider plans to travel to Malaysia and 10 other countries because of the virus.
Margaret Chan (left), director general of the World Health Organization, is among the dignitaries visiting a military base in Conakry, Guinea, on a tour of west African countries affected by Ebola. Also pictured: Guinean President Alpha Conde (fourth from right) and U.N. Secretary General Ban Ki-Moon (right).
Aedes aegypti mosquitoes are displayed at an exhibition on Jan. 28 in Brazil. The mosquitoes can be carriers of the Zika virus. Several cases of the virus have spread to Puerto Rico.
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A unidentified family member (right) of a 10-year-old boy that contracted Ebola has her temperature measured by a health worker outside an Ebola clinic on the outskirts of Monrovia, Liberia, on Nov. 20. Liberia, Guinea and Sierra Leone have now gone 42 days without a single reported case of Ebola.
Abbas Dulleh /AP
Medical workers surround 34-day-old Noubia, the last known patient to contract Ebola in Guinea, as she was released from a Doctors Without Borders treatment center in Conakry on Nov. 28.
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