COMPARISON OF FULL IMMUNISATION COVERAGE IN IBADAN NORTH-EAST AND IDO LOCAL GOVERNMENT AREAS, OYO STATE

Abstract

Nigeria is among the countries yet to achieve universal childhood immunisation coverage. Several studies have assessed immunisation coverage using the World Health Organization cluster survey which is limited in identifying specific areas with low coverage. Few studies had utilized Lot Quality Assurance Sampling (LQAS), to assess specific areas with unacceptable low coverage. This study was conducted to identify administrative wards with unacceptable full child immunisation coverage and compare overall coverage in Ibadan North-East (IBNE) and Ido Local Government Areas (LG As) of Oyo state. A cross-sectional survey involving 1,178 (IBNE = 588, Ido = 590) mothers with children aged 12-23 months was conducted. Using a two stage LQAS, 49 mothers from each of the 12 wards in IBNE and 59 mothers from each of the 10 wards in ldo were selected. A semi-structured interviewer-administered questionnaire was used to obtain information on socio-demographic characteristics, immunisation status and reasons for immunisation failure. Immunisation status was assessed using immunisation card and mother·s verbal report. Children were considered "fully-immunised" if they received Bacille Calmette Guerin (BCG), three doses each of Diphtheria, Pertussis and Tetanus, Oral Polio, and Hepatitis B, and one dose each of measles and yellow fever vaccines. Full child immunisation coverage per ward was unacceptable if the proportion of fully immunised children was <53% based on the estimate from the National Immunisation Coverage Survey, 2006. Samples were weighted based on the population by ward to estimate overall coverage in the two LGAs. Descriptive statistics, Chi-square test and logistic regression were used for data analysis. Mean ages of mothers were 28.5±5.6 and 28.1±6.0 years in IBNE and Ido respectively. The proportion of mothers with no education were 3.7% in IBNE and 18.1% in Ido, while traders were 66.5% and 51.5% in IBNE and Ido respectively. Majority of the children (59.1%) in IBNE received immunisation from public hospitals, while 55.7% in Ido received from Primary Health Center (PHC). Ten wards in IBNE and 8 wards in I<lo had unacceptable coverage. The weighted proportion of fully immunised children was 65.3% in IBNE and 42.2% in ldo. The BCG vaccine had the highest coverage i n both IBNE (81.0%) and ldo (71.7%) while yellow fever had the lowest; 41.5% and 38.8% respectively. Common reasons given for immunisation failure in both LGAs included fear of side effect (15.9%), unaware of the need for immunisation ( 13.0%) and travelled (11.3%). Mothers aged 15-24 years (OR: 1.9, 95%CI: 1.2-3.0), had no education (OR: 7.5, 95%CI: 2.6-21.7), and used outreach centre for immunisation (OR: 4.6, 95%CI: 2.3-9.0) were more likely to have incomplete immunisation in both LGAs. However, being a trader (OR: 2.1, 95%CI: 1.3-3.4) and living at a distance of ≥30mins from health facility (OR: 3.1, 95%CI: 1.2-7.8) were associated with incomplete immunisation in IBNE LGA. Lot Quality Assurance Sampling proved useful in identifying administrative wards with low immunisation coverage. The proportion of full immunisation coverage was lower in ldo. Measures to improve immunisation coverage should be targeted towards wards in both LGAs with unacceptable coverage.