Prevalence and Genetic Diversity of Coxsackievirus B in Iraqi Pediatric Patients with Type 1 Diabetes Mellitus

Abstract

The rate of infection and genetic diversity of Coxsackievirus B (CVB) in pediatric and teenagers with Type 1 Diabetes Mellitus (T1DM) were examined in a cross-sectional molecular study carried out at Al Diwaniyah Teaching Hospital between November 2023 and February 2024. Finding current CVB genotypes and assessing their relationship with diabetes with young onset were the targets. A total of 56 adolescents and children with T1DM participated in the study. Blood samples were used to obtain viral RNA, which was then transformed into complementary DNA (cDNA). To verify the presence of CVB RNA, the conserved part of the VP1 capsid gene was amplified using quantitative real-time PCR (qRT-PCR). Sanger sequencing and nested PCR were used to genotype the positive samples. SPSS v26.0 was used for statistical analysis. Results revealed CVB RNA in 20/56 patients (35.7%). The mean age of CVB-positive cases (7.34 ± 3.42 years) was significantly lower than CVB-negative patients (10.78 ± 3.37 years). The 1–5-year age group had the highest positivity rate (45%). Infections were more common among females (60%) and rural residents (55%). VP1 sequencing identified three genotypes: CVB3 (50%), CVB1 (30%), and CVB4 (20%). Sequence comparison demonstrated high nucleotide homology (99.26–99.87%) between Iraqi isolates and reference strains in GenBank. Conclusions: This study showed that several genotypes (B1, B3, and B4) common in Iraqi children with type 1 diabetes had a high prevalence of CVB infection. Younger children had higher infection rates, which lends trust to the idea that early viral exposure can cause autoimmunity.