Etiological surveillance of viral gastroenteritis in children aged less than 5 years in Tehran Province, Iran, 2023-2024.
BACKGROUND Acute gastroenteritis (AGE) is a primary cause of death in children less than five years old in low- and middle-income countries (LMIC), mostly caused by viral intestinal infections. While the disease poses a significant global burden, further investigation is needed to clarify the role of enteric viruses in disease pathogenesis. This work aimed to study the frequency of five major enteropathogenic viruses-Rotavirus (RV), Norovirus (NoV), Adenovirus (AdV), Sapovirus (SaV), and Astrovirus (AstV)- in stool samples of young children in Tehran, Iran, during 2023-2024. METHODS A cross-sectional study was conducted on 203 stool samples collected from children under 5 years of age clinically diagnosed with AGE. Viral genomic RNA was extracted and amplified for the most common AGE viruses using the RT-qPCR assay. RESULTS Out of 203 tested samples, 101 (49.8%) were positive for at least one of the viruses assessed. The most frequently detected enteropathogenic viral agents in children under 5 years were RV and AdV, while AstV was rarely detected. The positivity rate varies by age, gender, and season. Mixed infections were determined in 16 (7.9%) patients, with a predominance of RV and AdV. Infection with enteric viruses can occur throughout the year (peaking during mild-to-cold months), with fever, diarrhea, and nausea/vomiting being the most common symptoms among children. CONCLUSIONS Enteric viruses, particularly AdV and RV, contribute greatly to AGE among children in Iran. Continuous surveillance and long-term monitoring of enteropathogenic agents is essential to provide insight into the local circulation and characterization of AGE-causing viruses, guiding the implementation of targeted interventions and public health strategies to mitigate the risk of future outbreaks in the region.