Evaluation of Viral Respiratory Pathogens Among Patients Initially Tested Negative for SARS-CoV-2

Background: A number of ribonucleic acid (RNA) and deoxyribonucleic acid (DNA) viruses commonly circulating among vertebrates, such as influenza H1N1, respiratory syncytial virus (RSV), adenoviruses, and human coronavirus (HCoV)-229E, cause symptoms similar to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). These viruses are important causes of cold, pneumonia, and shortness of breath in humans, which have been overlooked during the coronavirus disease 2019 (COVID-19) pandemic. Furthermore, the diagnosis of infection with these viruses mostly relies on physical examination and clinical history, despite the fact that accurate molecular diagnosis is available. Objectives: This study aimed to evaluate the presence of respiratory viruses in patients who were suspected to be infected with COVID-19 yet initially tested negative for SARS-CoV-2, as it could be beneficial in developing effective control measures and more reliable testing and surveillance of such viruses. Methods: In this study, laboratory samples of 123 patients referred to Ghaem Hospital of Mashhad, Iran, were evaluated that tested negative for SARS-CoV-2 in the initial assessment while showing the clinical symptoms of COVID-19. Initial testing for SARS-CoV-2 was carried out by the TaqMan real-time polymerase chain reaction (PCR) method using a kit approved by the Ministry of Health (Pishtaz Teb, Iran). Further analysis for the presence of 17 respiratory viruses was carried out using Genova kits based on the virus genome conserved sequences of influenza H1N1, influenza B, influenza A, SARS-CoV-2, HCoV-HKU1, HCoV-OC43, HCoV-NL63, HCoV-229E, metapneumovirus, RSV, human bocavirus 1, 2, 3, parainfluenza 1, 2, 3, and adenovirus. Results: According to the results of the present evaluations, out of 123 samples that were acquired using nasal and throat swabs and that initially tested negative for SARS-CoV-2, 8 cases of influenza A (47.1%), 1 case of parainfluenza (5.9%), 1 case of HKU1/OC-43 (5.9%), 4 cases of RSV (23.5%), 1 case of HCoV-NL63/HCoV-229-E (5.9%), and 2 cases of SARS-CoV-2 (11.8%) were detected. Conclusions: Based on the results of real-time PCR tests obtained from patients who had clinical symptoms of SARS-CoV-2 infections, it can be mentioned that due to the similar symptoms of patients with respiratory viral infections, individuals with respiratory symptoms could be examined for other viral infections in addition to SARS-CoV-2 infection, and a suitable basis for their prevalence in the community could be provided.