the child was already in the clinic

Problem statement

A "missed opportunity for vaccination" (MOV) is WHO's term for "any contact with health services by an individual (child or person of any age) who is eligible for vaccination ... which does not result in the person receiving one or more of the vaccine doses for which he or she is eligible." The child is already in the building — brought for a fever, a weighing, a sibling's appointment — and leaves unvaccinated. Sridhar et al.'s systematic review of 45 LMIC studies (41,310 participants, 1991 onward) put the pooled MOV prevalence among children at 32.2% (95% CI 26.8–37.7) "with no change during the study period," and WHO's own page states that "the extent of MOVs have remained high (and unchanged)" for more than 30 years while "the underlying causes of MOVs have not changed significantly." WHO's assessment methodology (updated in 2015 and piloted in Chad and Malawi) found that 51% and 66% of eligible children respectively had at least one MOV on the survey day — and that during non-vaccination visits the rate was 77% (Chad) and 92% (Malawi), against 46% and 31% at vaccination visits. The unsolved problem is not vaccine supply, cold chain, or caregiver demand: it is that the routine behaviour of clinic staff at the sick-child window, the nutrition table and the maternal-health room does not include checking and completing a vaccination card, and thirty years of guidance saying it should has not changed that.

Why this matters

Global immunization strategy spends heavily on reaching "zero-dose" children who never touch the health system, yet a large share of under-vaccinated children are already making health-facility contacts that go unused. WHO notes that "interventions to reduce MOVs are generally low-cost and feasible in most settings," which is exactly what makes the persistence of the problem instructive: the constraint is not money or technology. In Chad and Malawi, 92% and 88% of health workers "were unable to correctly identify valid contraindications for vaccination," meaning eligible children are turned away for false contraindications such as a mild fever. Every MOV is a child returning later — or not — and a caregiver's trip wasted; at the coverage margins where measles outbreaks start, converting even a fraction of existing contacts into doses would move national coverage without a single additional outreach session.

What’s been tried and why it hasn’t worked

The remedy has been known and repeated since the 1990s — screen every child at every contact — and codified in WHO's ten-step MOV strategy (methodology updated 2015; planning guide, assessment methodology and intervention guidebook published 2017). Country assessments in Chad, Malawi, Kenya, Timor-Leste and Jordan all reproduce the same causal picture. Sridhar et al. catalogued 352 distinct reasons across studies, dominated by "health care practices, false contraindications, logistic issues related to vaccines, and organizational limitations, which did not vary by time or geographic region," and concluded that "the large number of identified reasons precludes standardized solutions." The Kenyan qualitative study makes the mechanism concrete: "there were no standardized practices for vaccination checks on all children, and identification of children needing vaccination was left to the discretion of the health worker," with checks often confined to vaccination visits ("[Vaccination]…that is the work of the MCH staff"); staff in curative departments do not see vaccination as their job; single-staff facilities tell caregivers to "come tomorrow because I am busy"; and workers "send mothers away because reluctant to open a vial of vaccine for one child" — a wastage-avoidance norm that is plausibly reinforced by how vial wastage is reported upward (an inference from the wider vaccine-wastage literature the Kenyan authors cite, not a finding stated in the Kenyan study itself). Ogbuanu et al. summarize the two binding barriers as "a lack of coordination between vaccination and curative health services and incomplete vaccination during vaccination visits." Training and job aids have been the default response, but the Kenyan findings show knowledge is only part of it: the failure sits in habits, role boundaries and wastage incentives at the individual clinic, which one-off training does not reach and which vary facility to facility.

What would unlock progress

The reframing the evidence points to is that MOV is a workflow-and-norms problem inside a single small organisation — a health centre — rather than a knowledge deficit or a supply problem, so the unlock is a facility-level behaviour-change design that (a) makes the vaccination-card check an unavoidable step at every patient-contact point (registration, triage, sick-child, nutrition), (b) resolves the multi-dose-vial dilemma explicitly (a stated policy that opening a vial for one eligible child is correct, with wastage reporting that does not punish it), and (c) is cheap enough to survive without project funding. Adjacent fields have solved structurally similar problems: surgical safety checklists and hospital hand-hygiene "moments" changed clinician habits by embedding a prompt in the workflow rather than by more training; opportunistic screening in primary care (blood pressure at any visit) is a direct analogue. Because reasons vary by facility, the tool must be a rapid local diagnosis-and-fix kit rather than a single national protocol.

Entry points for student teams

The door that needs no partner is WHO's own MOV toolkit, free to download without application — the planning guide, the assessment methodology, and the instruments themselves (health-facility exit survey, register form, health-worker knowledge-attitudes-practice questionnaire, focus-group discussion guide, pre-assessment checklist). A team can re-read the published Chad, Malawi and Kenya assessment findings against those instruments' own categories to work out which contact points — registration, triage, sick-child, nutrition, maternal health — leak the most eligible children, then prototype a low-cost card-check prompt for each (a registration-desk stamp, a colour tag on the weighing card, a one-line addition to the outpatient register) and deliver it with a pre-registered before-and-after evaluation plan the facility can run itself. Measuring eligible-but-unvaccinated exits inside a live clinic takes national ethics clearance, district or ministry permission and sustained on-site presence — access owned by the ministry of health and the facility's own management, not by a student team — so the semester deliverable is that trial's design rather than its results; a team that does have a reachable domestic partner can pilot the same prompt against a paediatric practice's immunization register, where missed opportunities also occur. A behavioural-design team could test message and incentive framings for the vial-opening dilemma with nurses and clinical students recruited through a school of nursing (what wording, and what reporting form, makes opening a ten-dose vial for one child feel like correct practice rather than waste). A systems team could build a facility-level MOV self-audit that a nurse-in-charge can run monthly from existing registers, using the WHO register form's fields as the data model. Relevant skills: human-centred design, implementation science, health-systems research, behavioural economics, and basic data analysis on facility registers.