At a Chinese hospital, a woman holds her child, who's receiving a rabies vaccine after being scratched by a cat. Vaccines against rabies were among the millions that were part of a newly discovered racket, reselling vaccines that hadn't been refrigerated.
A Pakistani health worker gives a polio vaccine to students in Peshawar, Pakistan, in March. Polio remains endemic in Pakistan after the Taliban banned vaccinations, attacks targeted medical staffers and suspicions lingered about the inoculations.
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.
Sean Hawkey/Sean Hawkey
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.