Vaccine hesitancy in the vaccination of children in Brazil

Since 2016, there has been a decrease in vaccination coverage for the childhood schedule of the National Immunization Program (PNI) in Brazil. To identify the reasons for vaccine hesitancy, we conducted a household survey of 31,001 live-born children living in the 26 Brazilian state capitals and the Federal District in 2017 and 2018. Census tracts were stratified according to socioeconomic status, we interviewed parents and/or guardians to collect information on the mother, child, reasons for not vaccinating, and other data. To identify the determinants of vaccine hesitancy, were used the "5Cs" (confidence, complacency and convenience, communication and context). Confidence: 94.5 % of parents/guardians of children trust the vaccines; 98.4 % believe it is important to vaccinate their children, and 20,0 % believe that vaccines are associated with serious adverse events. Complacency: 96.7 % decided to vaccinate their children with all the vaccines recommended; 7.2 % experienced difficulties with vaccination (distance and opening hours of the vaccination service, lack of time, problems with the child's health) despite going to the vaccination appointment; 22.9 % did not vaccinate their children (vaccine unavailable, clinic closed, health care provider absent, fear of adverse events). Communication: 24.5 % decided not to take their child for vaccination because of the pandemic; 24.4 % feared a reaction to the vaccine, and 9.2 % did not have the vaccine recommended by their doctor or health care provider. Socioeconomic status: vaccine confidence was lower among mothers with low education levels and lower-income families. Conclusions: Operational difficulties in the health care network were the main reasons for vaccine hesitancy in Brazilian state capitals during the study period. Although the proportion of parents/guardians who do not vaccinate their children voluntarily is low, this is a problem that needs to be consider so that it does not increase over time due to the infodemic.