Vaccine hesitancy, reactogenicity and immunogenicity of BNT162b2 and CoronaVac in pediatric patients with neuromuscular diseases

IntroductionCOVID-19 causes global health and psychosocial devastation, particularly to high-risk patients such as those with neuromuscular diseases (NMDs). The mRNA-based BNT162b2 and inactivated whole-virus CoronaVac are two novel COVID-19 vaccines widely used across the world that confer immune protection to healthy individuals. However, hesitancy towards COVID-19 vaccination was common for patients with NMDs early in the pandemic due to the paucity of data on the safety and efficacy in this specific patient population. Therefore, we examined the underlying factors associated with vaccine hesitancy across time for these patients and included the assessment of the reactogenicity and immunogenicity of these two vaccines. MethodsPediatric patients were screened from our NMD registry. For the vaccine hesitancy arm, those aged 8-18 years with no cognitive delay were invited to complete surveys in January and April 2022. For the reactogenicity and immunogenicity arm, patients aged 2-21 years were enrolled for COVID-19 vaccination between June 2021 to April 2022. Participants recorded adverse reactions (ARs) for 7 days after vaccination. Peripheral blood was obtained before BNT162b2 or CoronaVac and within 49 days after vaccination to measure their serological antibody responses as compared to healthy children and adolescents. ResultsForty-one patients completed vaccine hesitancy surveys for both timepoints, and 22 joined our reactogenicity and immunogenicity arm of the study. Two or more family members vaccinated against COVID-19 was positively associated with intention of vaccination (odds ratio 11.7, 95% CI 1.81-75.1, p=0.010). Pain at the injection site, fatigue and myalgia were the commonest ARs. Most ARs were mild (75.5%, n=71/94). All 19 patients seroconverted against the wildtype SARS-CoV-2 after two doses of BNT162b2 or CoronaVac, although there was lower neutralization against the Omicron BA.1 variant. DiscussionThis study demonstrated vaccine hesitancy amongst patients with NMDs was influenced by family members and changed across time. BNT162b2 and CoronaVac were safe and immunogenic even for patients on low-dose corticosteroids. Future research is required to assess the durability of the COVID-19 vaccines, the effectiveness of booster doses and other routes of administration against emerging SARS-CoV-2 variants for these patients.