The Ebola vaccine from a trial in Guinea needs to be kept at a temperature of minus 60 degrees Celsius, the World Health Organization says. Storage devices use jet fuel to keep the right temperature for up to five days in the field.
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A family receives treatment for cholera at a clinic run by Doctors Without Borders in Port-au-Prince, Haiti, in October 2011, a year after the overwhelming outbreak began.
A security fence surrounds the main part of the U.S. Army's Dugway Proving Ground, a testing laboratory in the Utah desert. The Army says it mistakenly shipped live anthrax from Dugway to several labs in the U.S. and Korea.
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