Continuing Barriers to Optimum Immunization Uptake in Nigerian Children: the Role of Missed Immunization Opportunities and Inappropriately Timed Immunizations

Abstract

Immunizations are effective means of disease prevention. Missed opportunities for immunizations and inappropriately timed immunizations have been shown to impact negatively on immunization coverage. Objective: To evaluate the role of missed opportunities (MOs) and inappropriately timed immunizations to optimal immunization uptake in Nigerian children. Methods: Records of 512 consecutive children attending an immunization clinic were reviewed. Data on the date of birth, and dates of immunization were extracted. The records were evaluated to determine the occurrence of MOs and that of inappropriately timed doses of vaccines. Results: Ninety percent of the missed opportunities occurred during the first visit with 43.2 percent, 48.2 percent and 6.3 percent of children not receiving the requisite BCG, HBVand OPV. Ultimately, 6.3 percent of the children did not receive BCG at all. Many children required extra visits to receive vaccines. Only 20 percent of those who made five visits were fully immunized, while this was achieved by 78 percent of those who made six visits. Four point four percent of vaccine doses were inappropriately timed and resulted in 7.2 percent decrease in coverage when invalid doses were excluded. Conclusion: Missed opportunities and inappropriately timed vaccinations remain barriers to optimal immunization uptake in Nigeria. As part of the strategy to strengthen routine immunization, training of health workers should stress the need to avoid MOs and inappropriately timed immunizations.