From Perception to Practice of Childhood Immunization in Karnataka, India: A Structured Narrative Review

Abstract

Background: Childhood immunization prevents substantial morbidity and mortality, but completion, timeliness, and equity remain important challenges in India. Karnataka, particularly Bengaluru, contains diverse populations including migrant and socioeconomically vulnerable communities. Caregiver knowledge and perceptions interact with access, service organization, and continuity of care.

Objective: To identify and synthesize published Indian evidence from 2020 to 2026 on caregiver knowledge, attitudes/perceptions, immunization uptake, timeliness, hesitancy, barriers, and determinants of routine childhood immunization, with particular attention to Karnataka and Bengaluru.

Methods: This structured narrative review draws on PubMed/MEDLINE-indexed literature, targeted web-indexed searches and backward citation checking for studies published from January 2020 through 8 October 2026. The available manuscript records did not retain complete date-stamped search histories, database exports, duplicate-removal logs, or screening decisions. The evidence is therefore synthesized narratively. PRISMA 2020 was consulted as a transparency framework.

Results: The manuscript represents 19 primary-study reports in its narrative synthesis spanning national NFHS analyses, Karnataka/Bengaluru studies, caregiver knowledge and hesitancy research, COVID-19 disruption studies, and a health-education intervention. National evidence indicates improvement in full immunization while timeliness and socioeconomic inequalities remain concerns. In a Bengaluru migrant-worker sample, 88.6% of children were fully immunized; inconvenient vaccination timing, lack of awareness, and parental work schedules were prominent reasons for dropout. Positive attitudes did not always correspond to detailed vaccine knowledge. Because the selection record is incomplete, the number of studies should be treated as the set represented in the current manuscript, not as a verified PRISMA inclusion count.

Conclusion: Indian evidence supports a multidimensional approach to childhood immunization that addresses knowledge, confidence, timeliness, documentation, service accessibility and continuity. For Karnataka and Bengaluru, practical caregiver education, card verification, due-listing, reminders, flexible session timing, catch-up vaccination and community follow-up are plausible programme responses. The evidence is heterogeneous and predominantly observational; causal inferences should therefore be made cautiously.