This is the Liboi village on the border between Kenya and Somalia…a land of dust and desperation. As part of its response to the crisis hitting the Horn of Africa, UNICEF is carrying out a massive immunization campaign across the drought affected areas, where half a million children face death due to starvation.

Olivia Yambi, UNICEF Kenya country representative, said: "We know that in large parts of this area, immunization coverage has been relatively low around 70 percent so at this time of enormous stress, it's very important to carry out supplementary immunization campaigns."

While the most obvious cure to malnutrition is food, it's not just hunger that can kill. Undernourished children can fall prey to diseases like polio and measles because of their low immunity.

In the coming few months, UNICEF and its partners aim to reach out to more than 200,000 children under the age of 5 with vaccines, Vitamin A supplements and de-worming tablets in Northern Kenya.

Mohamed Sheikh, provincial director of Ministry of Health in Kenya, said: "Because of the new influx of people you know who are coming from Somalia, and who are unimmunized, we are fearing that there will be outbreaks of diseases specially polio and measles. And that's why its important that we conduct this campaign so that we prevent those kind of outbreaks from happening. As we speak, there is already an outbreak of measles in the camps and outside the camps."

Health teams have been going from door to door to vaccinate children. Mohammed, district coordinator of the immunization campaign: "I'm so much committed to this exercise with all my heart and strength to make sure that every child is immunized against polio because I am a victim of polio and I know what a child goes through with polio."

Mohammad is making sure they don't miss a single child along the way. Their work is tough…they have to walk for hours and days in the harsh heat to reach children in remote areas. But heath workers say giving even one child the strength to survive makes their lives worth living.