Combining COVID-19 and seasonal influenza vaccines together to increase the acceptance of newly developed vaccines in the Eastern Mediterranean Region: a cross-sectional study

Background and aim The World Health Organization (WHO) recommended the concomitant administration (co-administration) of inactivated seasonal influenza and coronavirus disease 2019 (COVID-19) vaccines, encouraging the practice for the 2021-2022 flu season. This study aimed to assess the acceptance of simultaneously receiving the seasonal influenza vaccine (SIV) and the COVID-19 vaccine in a single administration to reduce vaccine rejection towards the COVID-19 vaccination.Methods An online-based cross-section survey was conducted from 1 September to 9 November 2022, in the Eastern Mediterranean Region (EMR) through distributing the survey on different social media platforms, including Facebook, Twitter, LinkedIn and WhatsApp. We used the multi-level model to assess the variation of vaccine countries across EMR countries.Results In total, 3300 participants were included in this survey from 11 countries distributed in the EMR. More than one-third (40.7%) were aged 18-25 years, 60.6% were females, 54.0% had a university degree, 43.1% had previous COVID-19, and 41.9% had relatives or friends who died from COVID-19. In total, 43.3% accepted this combination because it is less costly (9%), safer (18%), more effective (17%), and has fewer doses (19%). Rejection of this combination was due to fear of side effects (31%), and no studies have been published on their effects (31%). There was a significant difference across countries, which accounted for 6% of the variance in the log-odds of accepting the combined vaccination. Multi-level analysis revealed that being male, African and losing a family member or friend from COVID-19 increased the acceptance of the theoretical combined vaccines. Additionally, the number of doses taken of the COVID-19 and influenza vaccines separately significantly affected the combined vaccine acceptance. However, previous COVID-19 infection and older age reduced the odds of accepting the combined vaccines. Occupational level, social status and educational level didn't significantly affect the acceptance odds.Conclusions We can conclude that combining SIV and COVID-19 vaccines in one shot increased the overall acceptance of COVID-19 vaccines among vaccine rejectors.