Taking advantage of a 1993 truce in the Liberian civil war, the health authorities with the help of UNICEF and others launched a campaign to vaccinate the children of the capital, Monrovia. CIET assisted, shortly afterwards, in carrying out an evaluation of measles vaccination coverage and the children’s immune response in 18 representative sentinel sites. Blood samples were gathered onto filter paper by pricking the children’s fingers and analysed for measles antibodies. Vaccination coverage was 77%, but its efficacy, in terms of antibody production, was very different from one site to the other. The possible reasons for vaccine failure in some of the sites was the topic of a Master’s thesis by Dr Arcadio Morales of CIETmexico. The thesis, in Spanish, is available from the Library.