polio

An Afghan child was one of Gilkey's "little buddies." David P. Gilkey/NPR hide caption

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. Mohammad Sajjad/AP hide caption

A Pakistani mourner sits alongside bodies of blast victims following a bombing near a polio vaccination center at a hospital in Quetta. Banaras Khan/AFP/Getty Images hide caption

Measles, the reorganization of the World Health Organization and the Zika virus could all make global health headlines in 2016. Rich Pedroncelli, Raphael Satter, Felipe Dana/AP hide caption

If you're heading to China, check out the list of recommended vaccines. And be careful on that ice! Kevin Frayer/Getty Images hide caption

Ukrainian deputy minister of health Igor Pereginets holds a 2-year-old getting a polio vaccination in Kiev on October 21 — part of a campaign launched after two cases were reported in September. Genya Savilov/AFP/Getty Images hide caption

Polio survivors compete in a para-soccer tournament in Abuja, the capital of Nigeria. Lemmy Ijioma/Courtesy of Rotary International hide caption

Two polio cases have been reported in Ukraine, where some parents are fearful of vaccinations. Above: A child receives the diphtheria, whooping cough and tetanus vaccine in a children's hospital in Kiev. Sergei Chuzavkov/AP hide caption

A strain of polio virus, magnified. RCSB PDB hide caption

These two Portuguese language posters are pro-inoculation. The one at left, produced in 1977, says, "Vaccinate and protect the children." The one at right, from '87, sends a similar message, noting that vaccination offers an opportunity for every youngster. National Library of Medicine hide caption

A patch that's the size of a nickel could one day administer the measles vaccine. Gary W. Meek hide caption