What factors promote vaccine hesitancy or acceptance during pandemics? A systematic review and thematic analysis.

Examine the factors that promote vaccine hesitancy or acceptance during pandemics, major epidemics and global outbreaks. A systematic review and thematic analysis of 28 studies on the Influenza A/H1N1 pandemic and the global spread of Ebola Virus Disease. We found seven major factors that promote vaccine hesitancy or acceptance: demographic factors influencing vaccination (ethnicity, age, sex, pregnancy, education, and employment), accessibility and cost, personal responsibility and risk perceptions, precautionary measures taken based on the decision to vaccinate, trust in health authorities and vaccines, the safety and efficacy of a new vaccine, and lack of information or vaccine misinformation. An understanding of participant experiences and perspectives toward vaccines from previous pandemics will greatly inform the development of strategies to address the present situation with the COVID-19 pandemic. We discuss the impact vaccine hesitancy might have for the introduction and effectiveness of a potential COVID-19 vaccine. In particular, we believe that skepticism toward vaccines can still exist when there are no vaccines available, which is contrary to contemporary conceptualizations of vaccine hesitancy. We recommend conducting further research assessing the relationship between the accessibility and cost of vaccines, and vaccine hesitancy.