Peer-reviewed article
Immunization Coverage and Associated Factors Among Children Aged 18 to 72 Months in Communities With High Malaria Transmission, Bioko Island.
Esther Eburi Losoha, Maria Silvia A Lopez Mikue, Guillermo A García, Thabith Athuman, Amanda Ross et al. ·
Summary
Written by AI, not yet AICS's view · claude-haiku-4-5-20251001This study measured routine immunization coverage among children aged 18 months to 6 years living in malaria-endemic communities on Bioko Island, Equatorial Guinea. Only 29% of children were fully immunized according to the national schedule. Younger children (18 months to 2 years) had higher completion rates at 45% compared to only 22% in older children (2-6 years). Coverage estimates were similar whether information came from vaccination cards or caregiver recall.
Key points
- Overall immunization coverage was low at 29% (86 of 297 children fully immunized)
- Younger children aged 18 months to 2 years had significantly higher completion rates (45%) than older children aged 2-6 years (22%)
- Vaccination card data (28% coverage) and caregiver recall data (30% coverage) produced similar estimates
- Sex, ethnicity, and community area were not significantly associated with immunization status
- Study calls for further community-based research to identify reasons for vaccination gaps and inform targeted interventions
Limitations
The study is cross-sectional and cannot establish causation or track changes over time. The reasons for incomplete immunization are not investigated, limiting understanding of what barriers or program factors drive the low coverage.
Abstract
OBJECTIVE: To estimate routine immunization coverage, compare coverage estimates derived from vaccination cards and caregiver recall, and investigate factors associated with incomplete immunization among children aged 18 months to 6 years in communities with a high malaria prevalence in the Malabo district of Equatorial Guinea. METHODS: A cross-sectional survey was nested within a larger study and was conducted between September 2019 and March 2020. Children aged 18 months to 6 years living in 13 malaria-endemic communities in Malabo District, Bioko Island were enrolled. Immunization status was ascertained from vaccination cards or caregiver recall. RESULTS: Of the 297 children, with verified immunization status, 86 (29%) were fully immunized according to the national schedule. Coverage estimates were similar whether verified by vaccination card (28%, 34/121) or caregiver recall (30%, 52/176). Children aged 18 months and 2 years had higher completion rates than children aged 2-6 years: 45% (39/86) versus 22% (47/211), aOR = 0.42, 95% CI [0.20, 0.87]). The other factors examined (sex, ethnicity andcommunity area) were not significantly associated with immunization status. CONCLUSION: Overall immunization coverage in this population was low. Younger children had higher completion rates, possibly reflecting improved program performance in recent years or differential recall bias. Further community based studies, in both urban and peri-urban areas needed to identify reasons for gaps in vaccination coverage and to inform targeted interventions.
Findings the Hub has extracted
Each claim below is labelled by its type of design and links back to this report.
- Intervention
- Routine immunization program implementation according to national schedule
- Population
- Children aged 18 months to 72 months in 13 malaria-endemic communities in Malabo District, Bioko Island, Equatorial Guinea (n=297)
Key finding
Only 29% of children were fully immunized according to national schedule
Losoha et al. · PubMed (US National Library of Medicine) · 7 May 2026