Shifts in routine vaccine confidence during the COVID-19 pandemic in Kinshasa Province, DRC: A mixed-methods approach

The COVID-19 pandemic negatively impacted routine immunizations worldwide, decreasing confidence in vaccination programs. Leveraging a previously validated Shift in Vaccine Confidence (SVC) tool, we measured changes in routine HBV vaccine confidence due to the pandemic among Kinshasa-based participants and factors influencing vaccination confidence, uptake, and intention. We verbally administered SVC surveys in person to HBV-negative adults in Kinshasa who were ≥18 years of age, exposed to HBV in the household, and eligible for HBV vaccination. We measured HBV vaccination status in three ways: vaccinee, willing to receive HBV vaccination, or refused. We interviewed participants at one time point, during which they responded to prompts in the framework of (1) before and (2) during the pandemic. To measure shifts in vaccine confidence, we compared vaccination confidence before versus during the pandemic using Chi-square tests. We also coded open-ended responses to explore context-specific vaccine uptake and perception determinants. From April 2022 to February 2023, we administered the SVC tool to a purposive sample of 41 participants: 7 vaccinees, 23 willing to receive HBV vaccine, and 11 refusers. We observed statistically significant declines in opinion across all five vaccine confidence domains when comparing responses during versus before the pandemic (p<0.01). The most significant shift in perspective was that 80.5% of participants believed that vaccines were safe before the pandemic, compared to 46.3% during the pandemic (p<0.01). Qualitative analysis identified four emergent domains impacting uptake decisions: vaccine confidence, knowledge, risks, and external influences. Rising uncertainty about efficacy, safety, and distrust in the COVID-19 vaccine undermined vaccine confidence among our participants. Factors such as distrust in manufacturers and government, fear of side effects, perceived low illness risk, and inconvenient healthcare access contributed to low vaccine uptake. These insights underscore the pandemic's impact on routine immunization and emphasize the need for consideration in future vaccination campaigns.