<p>PLOS human subjects research checklist.</p>

Introduction

Market priming strategies use communication to prepare target audiences for service uptake when services become available. In 2025, a health worker strike in Abuja, Nigeria resulted in the suspension of HPV vaccination services for approximately four months. Services were temporarily restored for five days (July 16–20, 2025) during a Maternal, Newborn, and Child Health (MNCH) week. This study assessed whether caregiver recall of a digital market priming campaign was associated with HPV vaccine uptake during this brief service resumption.

Methods

We conducted a cross-sectional exit survey of 271 caregivers of adolescent girls aged 9–17 years attending vaccination sites during MNCH week. The survey collected data on socio-demographic characteristics, Facebook use, recall of HPV vaccine advertising on Facebook or Instagram, and caregiver-reported adolescent vaccination status. Survey findings were triangulated with administrative data on the number of HPV vaccinations delivered during the MNCH week. Analyses included descriptive statistics and multivariable logistic regression. A two-stage residual inclusion (2SRI) model was used as a sensitivity analysis to assess potential bias from unobserved confounding related to social media use. Ward-level regression analyses using administrative data compared vaccinations delivered in wards targeted by the digital campaign with those in non-targeted wards.

Results

Overall, 33.6% of caregivers recalled HPV vaccine advertising on Facebook or Instagram, and 64.2% reported that their adolescent had received the HPV vaccine. Message recall was associated with higher odds of caregiver-reported vaccination (adjusted odds ratio = 3.36; 95% CI: 2.75–4.11). Model-predicted marginal effects indicated a 23.3 percentage-point difference in reported vaccination probability between caregivers who did and did not recall messages, corresponding to an estimated 7.9 percentage-point difference in vaccination prevalence when applied to the caregiver population attending vaccination services. The 2SRI analysis found no evidence of endogeneity (p = 0.736). Administrative data were consistent with survey findings, suggesting an approximately 3 percentage-point higher vaccination coverage in wards targeted by the digital campaign compared with control wards during MNCH week.

Conclusions

Caregiver recall of a digital market priming campaign was associated with higher HPV vaccination uptake during a short-term resumption of services following a prolonged disruption. These findings suggest that insights-informed, subnational digital priming strategies—when combined with complementary offline approaches to ensure equitable reach—may help maintain caregiver readiness and support HPV vaccine delivery during periods of service instability.