The etiological evaluation of seasonal viral respiratory tract infections after the COVID-19 pandemic

The Etiological Evaluation of Seasonal Viral Respiratory Tract Infections After the Covid-19 Pandemic Introduction and Purpose: Acute respiratory infections are among the leading causes of death in children. The most common cause in children under five years of age is viral agents. Among these agents, İnfluenza, Respiratory Syncytial Virus (RSV) and Parainfluenza (PIV) viruses usually cause epidemics, while Human Coronavirus (HCoV), Human Rhinovirus (HRV), and Adenoviruses cause endemic infections. In this study, we aimed to determine the risk factors, seasonal differences and etiologic viral pathogens related to the post-pandemic period by retrospectively examining the identification of pathogens in patients admitted to Dicle University Children's Hospital after the Covid 19 pandemic with real-time PCR test (RT-PCR) to detect the causative agent and the relationship with patient-related variables. Materials and Methods: In this study, all patients between the ages of 1 month and 18 years who were admitted to Dicle University Medical Faculty (DUTF), Children's Hospital between 01.10.2022-01.05.2023 and in whom "Respiratory RT-qPCR MX-24S Panel" was studied were compared in terms of demographic, clinical, physical examination findings, which pathogen was detected, duration of hospitalization and comorbidity status. Patients in whom the causative agent was detected by Respiratory RT-qPCR MX-24S Panel were considered as Group 1 and those in whom the causative agent was not detected were considered as Group 2. Results: 330 patients, 204 of whom were male, were included in the study. The mean age was 52.04±50.39 months (min=1 max=180). Hospitalisation rate was 40.9%. A statistically significant correlation was found between Rt-PCR positivity and age groups, presence of comorbidities, presenting complaints such as fever, cough, respiratory distress, chest pain, nausea and vomiting, rash and peeling of hands and feet (p=0.001, p<0.001, p=0.035, p=0.039, p=0.003, p=0.031, p=0.043, p=0.050, p=0.008, respectively). Influenza A virus was most frequently detected in (n=47;14.2%) patients, (n=35;74.5%) in January and 9(19.1%) in December. The most common virus co-infections were Adenovirus-RSV with a rate of 27.2% and HCoV-RSV with a rate of 27.2%. Among the bacterial superinfection agents, only Haemophilus influenzae was found to be statistically significantly associated with hospitalisation (p=0.017). Conclusion: PCR, which is a rapid method with high sensitivity and specificity, enables the detection of viral agents of respiratory tract infections, the initiation of appropriate antiviral treatments, the termination of unnecessary antibiotic use, and the determination of the seasonal distribution of viral agents and target age groups and the necessary measures for public health. Keywords: Respiratory virus, COVID-19, coinfection, real-time PCR, child.