Background Respiratory tract infections (RTIs) continue to be a major global health concern, particularly among infants, the elderly, and individuals with chronic illnesses. The circulation patterns of respiratory viruses have shifted considerably after the COVID-19 pandemic, emphasizing the need for updated regional data. This study assessed the distribution, age-related trends, and seasonal behavior of common respiratory viruses in northwestern Saudi Arabia using multiplex PCR diagnostics. Methods This retrospective observational study was conducted on 3,809 respiratory samples collected at King Salman Armed Forces Hospital, Tabuk, between November 2022 and April 2025. All specimens were analyzed using the Xpert Xpress CoV-2/Flu/RSV Plus assay (Cepheid, Sunnyvale, CA, USA) to detect SARS-CoV-2, influenza A, influenza B, and respiratory syncytial virus (RSV). Demographic variables, pathogen frequencies, coinfection patterns, and seasonal variations were examined. Associations between age groups and viral detection were evaluated using chi-square and Fisher’s exact tests. Results Among 3,809 samples, 1,197 (31%) tested positive for at least one respiratory pathogen. RSV was the most frequently detected virus (39%), followed by influenza A (33%) and SARS-CoV-2 (19%). Single-pathogen infections accounted for 97% of positive cases, while 3% demonstrated coinfections, most commonly RSV plus influenza A and SARS-CoV-2 plus influenza A. Viral detection varied significantly by age (p < 0.001). Children under five years had the highest positivity rate, with RSV dominating this age group. In contrast, influenza A and SARS-CoV-2 were more common among older adults. Seasonal analysis revealed winter peaks for RSV, influenza A, and SARS-CoV-2. Conclusions Respiratory viral infections in northwestern Saudi Arabia demonstrate distinct age-related and seasonal patterns, with RSV predominating in young children and influenza A and SARS-CoV-2 more common in older age groups. These findings highlight the importance of continuous molecular surveillance and the role of multiplex PCR diagnostics in guiding clinical management and antimicrobial stewardship. Further prospective studies incorporating clinical severity outcomes are warranted to better assess the public health impact of respiratory viral infections in this region.
Manghrio et al. (Sun,) studied this question.