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.