The impact of COVID-19 vaccination campaign on pediatric vaccine uptake based on parents' attitudes towards mandatory and recommended vaccination in Southern Italy.

INTRODUCTION: This study investigates the association between parental attitudes towards mandatory and recommended vaccines in the National Immunization Plan (NIP) of Italy and their acceptance of the COVID-19 vaccine in children aged 5-11 years. METHODS: Using data from approximately 42,000 children in Southern Italy, parental attitudes towards previous vaccinations were examined. Mandatory and recommended vaccinations were considered for the analysis, with the first shot of each schedule being considered relevant, regardless of when it was administered or whether the recommended number of doses was administered. A multivariate logistic regression was performed to analyze associations between the covariates of age, sex, adherence to mandatory vaccinations, number of recommended vaccinations, and COVID-19 vaccination. RESULTS: The COVID-19 vaccine acceptance rate was 50.7% in our sample. We revealed a strong association between parental attitudes towards previous vaccinations and the acceptance of the COVID-19 vaccine. Mandatory vaccinations under the NIP showed the highest acceptance rates, and among non-mandatory vaccines, the pneumococcal conjugate vaccine had the highest acceptance rate, potentially due to its co-administration with the hexavalent vaccine. The study identified a trend of lower COVID-19 vaccine coverage in younger children. CONCLUSIONS: The study underscores the importance of co-administration approaches and well-planned vaccination schedules in enhancing vaccine coverage. It suggests that integrating newer vaccines, like the COVID-19 vaccine, into established vaccination schedules could potentially increase acceptance and coverage. The findings highlight the urgency of addressing vaccine hesitancy, particularly in the pediatric population, to ensure high vaccination coverage and effective disease control. Further research is needed to explore the potential strategies to increase vaccine acceptance.

Performance comparison between heterologous and homologous COVID19 vaccine schedules on Omicron variant incidence: A real-world retrospective cohort study in Southern Italy.

As the COVID19 pandemic progresses, there is an increasing need to evaluate the performance of vaccine strategies. This study investigated the vaccine schedule performance of heterologous vaccination compared to homologous vaccination in preventing Omicron SARS-CoV2 infection in the adult population. This retrospective cohort study utilized data from the Infections Regional Information System and the Apulia Regional Vaccine Registry to identify individuals who received a booster dose of one of 14 different COVID19 vaccination schedules between September 2021 and August 2022 in the province of Lecce, Southern Italy. The standardized cumulative incidence of SARS-CoV2 infection after the booster dose was assessed and the risk of infection between subgroups of heterologous and homologous vaccination schedules was compared using the Cochran-Mantel-Haenszel test. A total of 469,069 subjects were included in the study. The standardized incidence of SARS-CoV2 infection varied greatly among different vaccine schedules, with the highest and lowest being AZ-AZ-BNT (34.7 %) and MOD-MOD-BNT (18.9 %), respectively, and some heterologous schedules performing better than homologous ones. The risk of SARS-CoV2 infection was significantly lower in individuals who received specific heterologous vaccination schedules compared to homologous vaccination schedules, the best performing being MOD-MOD-BNT with a common odd ratio of 0.661 (IC. 95 % [0.620-0.704]). This study provides evidence that heterologous vaccination schedules may be more effective in preventing Omicron SARS-CoV2 infection compared to homologous vaccination schedules, highlighting how the vaccine product, rather than the platform, is involved in the different protection provided by heterologous vaccination.