Clutching an umbrella, medical records and her 2-year-old daughter, Kani Fall negotiated the brown puddles lapping at the hospital gate, the final hurdle in a two-hour, rain-soaked journey to her nearest vaccination clinic in western Gambia.

Fall waited with dozens of mothers and babies in the flooded courtyard of Bundung Hospital. Then a doctor emerged with bad news. The hospital had run out of measles vaccines, and it wasn't clear when they would receive more.

"They told me there was no vaccine. But I am coming back," said Fall, 27, who had closed her catering business for the day to make the trip. "It's for my daughter, it's for her health," she added, fighting back tears of frustration.