Routines, Disruptions, Revised Decisions: A Biographical Analysis of Vaccination Trajectories among Filipino Caregivers

"Given the evidence for intrapersonal changes in vaccination attitudes, more in-depth explorations of the developments of vaccination attitudes over the course of a person's life could provide starting points for targeted vaccine promotion efforts."

Individuals' vaccine attitudes and practices are not static but, instead, are shaped and iteratively revised based on new information and experiences. However, insights into the dynamic nature of vaccine biographies across the life course are limited, particularly from low- and middle-income countries (LMICs). This paper aims to contribute to filling this gap in the literature by investigating life-course vaccination trajectories of caregivers in the Philippines, where a large-scale dengue vaccine controversy has dealt a critical blow to vaccine confidence.

As outlined here, in November 2017, Sanofi Pasteur released information that their dengue vaccine (Dengvaxia), which had been rolled out in the Philippines for over a year, predominantly to schoolchildren, increased risks for a specific subgroup of vaccine recipients. While the Dengvaxia vaccine programme was immediately halted, a highly politicised controversy ensued. Large-scale outbreaks of measles followed shortly thereafter, and the Philippines lost its 19-year polio-free status. Just as vaccine confidence seemed to be rebounding, the COVID-19 pandemic and associated lockdowns, as well as strict and controversial COVID-19 vaccine mandates, resulted in the Philippines becoming among the top 20 countries with the highest absolute number of unvaccinated children worldwide in 2022.

To explore vaccination biographies in this setting, characterised by high proportions of vaccine hesitancy (VH), in June 2022, the researchers conducted and biographically analysed 29 narrative in-depth interviews with caregivers of small children in two urban and two rural barangays (smallest administrative unit in the Philippines) in the Calabarzon region, southwest of the Manila metropolitan area.

The results outline how the perceived relevance of vaccination and an individual's own attitudes and practices repeatedly changed over the course of their life. While respondents narrated vague memories of early vaccine encounters in their families, at schools, or during vaccination campaigns, vaccine relevance accelerated drastically during respondents' or their partner's first perinatal period. Some mothers, particularly those who became pregnant with their first child at an earlier age, recounted that they did not feel informed or confident enough to make their own decision about their child's vaccination, but that they instead relied on older, and in their eyes more experienced, family members.

Over the following life phase as caregivers, respondents described iterative shifts in their vaccine stance (based on their own experiences, broader discourses, or changing contexts) until their youngest child had completed (or was perceived to have outgrown) the recommended childhood immunisations. For example, some respondents outlined how negative vaccine-related reporting, especially during Dengvaxia and COVID-19 discourses, caused them to reject vaccines.

Respondents' later adulthood and old age were commonly marked by little engagement with immunisation (except for the COVID-19 vaccines), until the birth of grandchildren sparked renewed motivation to guide younger generations (whether for or against vaccination). The authority of elderly community members was not limited to their own family; instead, one vaccine hesitant respondent recounted how her own mother had been advised by an elderly community member to not vaccinate her children.

In short, across life phases, the results indicate caregivers' repeated and multidirectional changes in vaccine attitudes and practices over the life course, mirroring previous scholarship. However, while respondents in existing studies predominantly exhibited one (from VH to vaccine confidence or vice versa) or two (e.g., from confidence to hesitancy and back to confidence) changes in their trajectories, caregivers in this study often narrated less clear patterns and several shifts in their perception of vaccination relevance over the course of their lives. The researchers suggest that the frequent and multidirectional changes in the data might also link to specific characteristics of the Philippines or LMIC settings. They call for future research across societal groups and settings to explore how setting-specific contextual factors emerge within individuals' vaccine biographies.

The researchers suggest that vaccine promotion efforts could incorporate biographical dynamics to align with respondents' informational needs - for example, by increased engagement in first perinatal periods, eye-level communication at later phases to acknowledge caregivers' increased sense of expertise, and encouragement of vaccine-confident grandparents to engage in younger generations' vaccination decisions.

In conclusion, researchers and practitioners may wish to acknowledge how vaccine behaviours (both rejection and acceptance) observed at a specific point in time do not necessarily remain stable over the life course. They can repeatedly change based on intrapersonal developments, new experiences, information, or societal discourses. The researchers recommend personalised approaches that reflect both an individual's spatial setting and their temporal situatedness within personal vaccine biographies to sustainably foster vaccine confidence and provide required information at vulnerable biographical points.