Villagers in Sabbatum gather for a round of polio vaccinations. Immunizers travelled through harsh rains to reach this small village – providing one of the few health services currently available to these children. 'Micro-planning' for polio eradication includes creating maps of each village, which also lays the groundwork for future public health campaigns.

Armed guards accompany immunizers during Somali National Immunization Days (NIDs), as clan warfare continues to fracture this country. UN agencies negotiate with numerous factions to ensure access to every community during NIDs.

After all the children under five in a household have been immunized, health workers mark the house to show it has been covered, in a suburb of Ghaziabad, a city in Uttar Pradesh. Uttar Pradesh and Bihar are the only states in India where wild poliovirus is still circulating. In an all-out effort to eliminate the virus, entire districts are being blanketed with 'door-to-door' campaigns that literally target every house.

A child is vaccinated in the village of Agepic in Rumbek county. Vaccinators and polio surveillance teams rely on UN relief flights to access remote southern parts of this vast, sparsely populated country.