Global Misinformation Meets Local Context: COVID-19 Vaccine Conspiracy Theories and Their Impact on Immunization Acceptance in Nigeria

Background Conspiracy theories about COVID-19 vaccines containing microchips or tracking devices have spread globally, but their penetration and influence in sub-Saharan African populations remain poorly understood. Understanding how global misinformation narratives affect vaccination acceptance is crucial for developing effective immunization strategies in low- and middle-income countries. Methods We conducted a cross-sectional survey from October 2020 to April 2021 across Nigeria's six geopolitical regions using convenience sampling. Adults aged 18 years and above from urban, rural, and informal settlements completed structured interviews about COVID-19 vaccine intentions, specific conspiracy beliefs, information sources, and trust networks. Multivariable logistic regression identified factors associated with conspiracy theory endorsement and vaccine refusal. Results Among 870 participants, 742 were vaccine-hesitant, with 89.4% endorsing at least one conspiracy theory. Microchip or tracking device theories were cited by 32.1% of vaccine-hesitant individuals as their primary concern, making this the most prevalent specific reason for vaccine refusal. Overall vaccine acceptance was only 14.7%, with conspiracy theory believers showing near-universal refusal (2.9% acceptance vs 24.1% among non-believers, p < 0.001). Conspiracy theory endorsement was associated with lower educational attainment (aOR = 2.34, 95% CI: 1.45–3.78), rural residence (aOR = 1.87, 95% CI: 1.23–2.84), and obtaining health information primarily from social networks (aOR = 3.12, 95% CI: 1.98–4.91). Conclusions COVID-19 vaccine conspiracy theories have achieved widespread penetration in Nigerian communities, becoming the dominant driver of vaccine refusal. These findings demonstrate how globally circulated misinformation can undermine local immunization programs and highlight the urgent need for culturally-adapted counter-misinformation strategies that engage trusted community intermediaries.