Viral Etiology Associated With Acute Respiratory Tract Infection Patients in Bangkok, Thailand.

Background Acute respiratory infections (ARIs) are a significant public health concern globally. After the relaxation of COVID-19 containment measures, there has been an increase in respiratory tract infections. However, the epidemiological data on circulating respiratory pathogens after the COVID-19 pandemic in Bangkok, Thailand are interesting. We conducted a study on the respiratory pathogens detected in patients with ARIs in 2023. Methodology This retrospective study utilizes archived nasopharyngeal swab samples from patients with ARIs of all ages at Bangpakok 9 Hospital between January and December 2023. These samples were collected when physicians ordered multiplex polymerase chain reaction testing as part of the diagnostic investigation. All samples were tested for 23 types of respiratory viruses and bacteria using multiplex reverse transcription-polymerase chain reaction (QIAstat-Dx, Qiagen) testing. Results Of 321 patients, viral pathogens were found in 78.5% of cases, with 21.5% remaining unidentified. Most patients (47%) were aged between two months to five years. The most common pathogen identified was rhino/enterovirus (28.0%), followed by human parainfluenza virus (15.1%), influenza virus (12.0%), respiratory syncytial virus (9.9%), human metapneumovirus (9.5%), adenovirus (9.2%), bocavirus (8.0%), and coronavirus (5.5%). Interestingly, the prevalence of SARS-CoV-2 infection was relatively low at 2.8%. Moreover, viral co-infection was observed in 25% of cases. Monthly distribution revealed the fluctuating prevalence of detected respiratory pathogens co-circulation throughout the year. In addition, the proportion of identified pathogens varied among patients across all age groups. Conclusions Our study reported the high prevalence of respiratory pathogens in ARI patients of all ages after the COVID-19 pandemic. The most prevalent respiratory pathogens among ARI cases were viruses, particularly rhino/enterovirus. The data hold significance for physician awareness regarding diagnosis, treatment, and the implementation of infection control strategies in cases of ARIs.