Factors Associated with Timely First-Dose Pentavalent and Measles-Rubella Vaccination: A Cross-Sectional Study in...

Immunization coverage varies across Papua New Guinea. In East New Britain (ENB) Province in 2022, only 65.5% and 50.2% of children under one year received their first dose of pentavalent (DTP1) and measles-rubella (MR1) vaccine, respectively. This study aimed to examine barriers and enablers to routine immunization in areas of un(der)-vaccination in ENB.

A face-to-face survey was conducted with caregivers of children aged 12-23 months in ENB. We used Poisson regression to calculate incidence rate ratios (IRR) and 95% confidence intervals (95% CI) for factors associated with timely receipt of DTP1 or MR1 vaccines, defined as a child who was vaccinated between -2 and +30 days of the vaccine schedule. Delayed receipt is defined as a child who was vaccinated >30 days from the recommended due date.

Among 237 caregivers surveyed, 59.9% of children were vaccinated within the "timely" window for DTP1 and 34.1% for MR1. Timely DTP1 receipt was associated with a facility-based birth (IRR:1.93; 95% CI: 1.10-3.38) and trusting healthcare workers "very much", compared to "a little or moderately" (IRR:1.53; 95% CI: 1.17-1.99). For MR1, the caregiver having completed tertiary/vocational education (IRR:1.79; 95% CI: 1.15-2.78), reporting taking a child to be vaccinated is affordable (IRR:1.52; 95% CI: 1.04-2.22), and healthcare workers explaining immunization services and answering associated questions (IRR:1.68; 95% CI: 1.18-2.41) were associated with timely vaccination.

Activities to improve timely vaccination in ENB could include strengthening healthcare worker interpersonal communication skills to optimize trust and incentivizing women to give birth in a health facility.