Objective: COVID-19 has become a global pandemic since March 2020. Vaccination is essential as there is no cure for COVID-19 infection yet. Vaccination is important for individuals with Type-1 DM because Type-1 Diabetes Mellitus (DM) is also considered among the medical conditions that can increase the risk of severe illness in children. One of the most important reasons for vaccine refusal in parents of children with chronic diseases is anxiety about developing side effects after vaccination. With this study, we aimed to detect the side effects of the vaccination in children with Type-1 DM who are vaccinated against COVID-19 by comparing them with children who do not have any chronic diseases.

Material and Method: We compared the side effects of the vaccine in 34 children with type 1 DM who were vaccinated against COVID-19 and 34 children who were also vaccinated against COVID-19 without any chronic disease. The survey forms about the side effects that may occur after the COVID-19 vaccine, developed by the researcher in line with the literature, was filled out by the patient and/or their parents via the Google survey forms.

Results: The most common local side effect was pain at the injection site with 88.20%, while swelling was 26.50%, and redness was 17.60%. There was no statistical difference between the groups in the rate of occurrence of local side effects (p >0.05).

Conclusion: Our results show that post-COVID-19 vaccine side effects are generally local, mild and, prevalent, as well as systemic/severe reactions are rare. Side effects related to the COVID-19 vaccine in patients with type-1 DM were similar to the control group. Our study could be useful in reducing anxiety about vaccine-related side effects in this group of patients and their parents.