COVID-19 infection and inactivated vaccination: Impacts on clinical and immunological profiles in Chinese children with type 1 diabetes.

BACKGROUND

The coronavirus disease 2019 (COVID-19) pandemic has been linked to an increased incidence of diabetes and diabetic ketoacidosis (DKA). However, the relationship between COVID-19 infection and progression to type 1 diabetes (T1D) in children has not been well defined.

AIM

To evaluate the influence of COVID-19 infection and inactivated vaccine administration on the progression of T1D among Chinese children.

METHODS

A total of 197 newly diagnosed patients with T1D were retrospectively enrolled from Children's Hospital of Fudan University between September 2020 and December 2023. The patients were divided into three groups based on their history of COVID-19 infection and vaccination: the infection group, the vaccination-only group, and the non-infection/non-vaccination group. Comprehensive clinical assessments and detailed immunological evaluations were performed to delineate the characteristics and immune responses of these groups.

RESULTS

The incidence of DKA was significantly higher in the COVID-19 infection group (70.2%) compared to the non-infection/non-vaccination group (62.5%) and vacscination-only group (45.6%; = 0.015). Prior COVID-19 infection was correlated with increased DKA risk (OR: 1.981, 95%CI: 1.026-3.825, = 0.042), while vaccination was associated with a reduced risk (OR: 0.558, 95%CI: 0.312-0.998, = 0.049). COVID-19 infection mildly altered immune profiles, with modest differences in autoantibody positivity, lymphocyte distribution, and immunoglobulin levels. Notably, positive children with a history of COVID-19 infection had an earlier T1D onset and lower fasting C-peptide levels than the negative children with a history of infection (both < 0.05).

CONCLUSION

COVID-19 infection predisposes children to severe T1D, characterized by enhanced DKA risk. Inactivated vaccination significantly lowers DKA incidence at T1D onset. These findings are valuable for guiding future vaccination and T1D risk surveillance strategies in epidemic scenarios in the general pediatric population.