Childhood immunisation in Bungoma County, Kenya, from 2008 to 2011: need for improved uptake.

Uptake of immunisations in children aged 1-2 years in Bungoma County, Kenya, was determined as part of the 6-monthly Health and Demographic Surveillance System surveys. A total of 2699 children were assessed between 2008 and 2011. During this time period, full immunisation declined significantly from 84% to 58%, and measles vaccine declined uptake from 89% to 60% (P < 0.001). Each year there was a significant fall-off for the third doses of the oral polio and pentavalent vaccines (P < 0.001). These findings are of concern, as low immunisation coverage may lead to vaccine-preventable disease outbreaks. Further investigations into the reasons for declining immunisation trends are required.