Clinical Multimodal Surveillance of Respiratory Syndrome Pathogens

Inclusion Criteria: * Patients with respiratory syndrome: Eligible patients are those diagnosed with respiratory syndrome based on the predefined data dictionary and the following ICD-10 (International Statistical Classification of Diseases, 10th Revision) diagnosis codes: R05, R50, J00, J01, J02, J03, J04, J06, J07, J08, J09, J10, J11, J12, J13, J14, J15, J16, J17, J18, J20, J21, J98.414, and J98.802. * Patients with respiratory syndrome: Eligible patients are identified using the following search criteria. Patients meeting any one of the following criteria should be included: 1. Medical history (History of Present Illness): Positive test result for a respiratory syndrome-related pathogen. 2. Laboratory testing: Positive test result for a respiratory syndrome-related pathogen. 3. Medication: Receipt of any of the following antiviral agents: Nirmatrelvir/Ritonavir Leritrelvir Xiannuotewei/Ritonavir Molnupiravir Azvudine Deuremidevir 4. Diagnosis: Diagnosis containing the term "respiratory tract infection." Exclusion Criteria: * Participants who may compromise the study results: Patients who are unable to provide a specimen or whose specimen volume is insufficient for laboratory testing. * Participants who are unable to comply with study procedures.