Missed opportunities and inappropriately given vaccines reduce immunisation coverage in facilities that serve slum areas of Nairobi

Abstract

Objectives: To quantify missed opportunities for immunisation, document reasons for their occurrence and evaluate the extent of inappropriately given vaccine doses. Design: A cross sectional study of children under two years of age attending health facilities. Setting: Six health facilities predominantly serving the slums of Nairobi. Methodology: Information on vaccination was extracted from child immunisation cards as well as from mothers or guardians of children. Results: Effective immunisation coverage for Bacille-Callmette Guerin (BCG) was 91%. Coverage for the birth dose, first, second, and third doses of oral polio vaccine (OPV0, OPVI, OPV2, and OPV3) was 44%, 83%, 79% and 75% respectively. Effective coverage for first, second and third doses of diphtheria-pertusis-tetanus (DPTI, DPT2 and DPT3) vaccine was 88%, 87% and 85% respectively. Measles coverage was 80%. Immunisation coverage for all antigens except OPV0 and OPV3 would have been increased to over 90% had missed immunisation opportunities and inappropriately administered vaccination been avoided. There would have been an 11% increase in OPV3 coverage to 86%. Increases in coverage for OPVI and OPV2 would have been 16% and 18% respectively. Coverage would have increased by 10% for diphtheria pertusis-tetanus (DPT) doses DPTI and DPT2, and 7% for DPT3. Measles immunisation coverage would have increased by 19% had missed immunisation opportunities and inappropriately administered vaccinations been avoided. The overall missed opportunities rate was 3%. The proportions of missed opportunities were higher for the OPV series than DPT series. Conclusion: Missed immunisation opportunities among clinic attendees in Nairobi occur and routine supervision should be strengthened in these health facilities in order to minimise such missed opportunities and inappropriately administered vaccines.