[Korea 2022-2023 Influenza and Respiratory Viruses Laboratory Surveillance Report]

During the 2022-2023 season, spanning 36 weeks in 2022 and 35 weeks in 2023, we performed real-time reverse transcription polymerase chain reaction tests on 15,009 respiratory specimens to analyze the causative pathogens and viral characteristics. Of these, 1,341 cases (8.9%) tested positive for influenza. Among positive cases, 1,085 cases (80.9%) were identified as A(H3N2), 211 (15.7%) as A(H1N1)pdm09, and 45 (3.4%) as type B. Genotype analysis confirmed similarity to vaccine strains. Furthermore, antigens from isolated influenza viruses exhibited effective neutralizing activity against vaccine strains and lacked resistance to oseltamivir, zanamivir, and peramivir treatments. Regarding other respiratory viruses, Rhinovirus was the most prevalent, detected in 1,978 cases (13.2%), followed by adenovirus (1,564 cases, 10.4%), metapneumovirus (1,456 cases, 9.7%), parainfluenza virus (1,430 cases, 9.5%), respiratory syncytial virus (1,139 cases, 7.6%), bocavirus (794 cases, 5.3%), and human coronavirus (742 cases, 4.9%). Following the relaxation of coronavirus disease 2019 control measurements, we observed a seasonal increase in respiratory viral diseases, highlighting the importance of national respiratory viral surveillance. Our department remains committed to closely monitoring causative pathogens and analyzing influenza virus trends and characteristics.