Influenza A, Influenza B, human respiratory syncytial virus and SARSCoV-2 molecular diagnostics and epidemiology in the post COVID-19 era

• Published in: Respiratory research Vol. 25; no. 1; pp. 234 - 9
• Main Authors: Luštrek, Manca, Cesar, Zala, Suljič, Alen, Kogoj, Rok, Knap, Nataša, Virant, Monika Jevšnik, Uršič, Tina, Petrovec, Miroslav, Avšič-Županc, Tatjana, Korva, Miša
• Format: Journal Article
• Language: English
• Published: London BioMed Central 05.06.2024; BioMed Central Ltd; BMC
• Subjects: Adult; Aged; Analysis; Co-detections; Coinfection - diagnosis; Coinfection - epidemiology; COVID-19 - diagnosis; COVID-19 - epidemiology; Epidemiology; Female; Flu-A/B; Health aspects; HRSV; Humans; Influenza; Influenza A virus - genetics; Influenza A virus - isolation & purification; Influenza B virus - genetics; Influenza B virus - isolation & purification; Influenza, Human - diagnosis; Influenza, Human - epidemiology; Influenza, Human - virology; Laboratories; Male; Medicine; Medicine & Public Health; Microbiology; Middle Aged; Molecular Diagnostic Techniques - methods; Multiplex; Pneumology/Respiratory System; Prevention; Respiratory Syncytial Virus Infections - diagnosis; Respiratory Syncytial Virus Infections - epidemiology; Respiratory Syncytial Virus, Human - genetics; Respiratory Syncytial Virus, Human - isolation & purification; Risk factors; rtRT-PCR; SARS-CoV-2; SARS-CoV-2 - genetics; SARS-CoV-2 - isolation & purification; Seasons; Testing; Slovenia; SARS-CoV-2; Flu-A/B; Multiplex; Co-detections; HRSV; rtRT-PCR; Turnaround-time
• ISSN: 1465-993X; 1465-9921; 1465-993X
• DOI: 10.1186/s12931-024-02862-7

Background The concurrent circulation of SARS-CoV-2 with other respiratory viruses is unstoppable and represents a new diagnostic reality for clinicians and clinical microbiology laboratories. Multiplexed molecular testing on automated platforms that focus on the simultaneous detection of multiple respiratory viruses in a single tube is a useful approach for current and future diagnosis of respiratory infections in the clinical setting. Methods Two time periods were included in the study: from February to April 2022, an early 2022 period, during the gradual lifting of COVID-19 prevention measures in the country, and from October 2022 to April 2023, the 2022/23 respiratory infections season. We analysed a total of 1,918 samples in the first period and 18,131 respiratory samples in the second period using a multiplex molecular assay for the simultaneous detection of Influenza A (Flu-A), Influenza B (Flu-B), Human Respiratory Syncytial Virus (HRSV) and SARS-CoV-2. Results The results from early 2022 showed a strong dominance of SARS-CoV-2 infections with 1,267/1,918 (66.1%) cases. Flu-A was detected in 30/1,918 (1.6%) samples, HRSV in 14/1,918 (0.7%) samples, and Flu-B in 2/1,918 (0.1%) samples. Flu-A/SARS-CoV-2 co-detections were observed in 11/1,267 (0.9%) samples, and HRSV/SARS-CoV-2 co-detection in 5/1,267 (0.4%) samples. During the 2022/23 winter respiratory season, SARS-CoV-2 was detected in 1,738/18,131 (9.6%), Flu-A in 628/18,131 (3.5%), Flu-B in 106/18,131 (0.6%), and HRSV in 505/18,131 (2.8%) samples. Interestingly, co-detections were present to a similar extent as in early 2022. Conclusion The results show that the multiplex molecular approach is a valuable tool for the simultaneous laboratory diagnosis of SARS-CoV-2, Flu-A/B, and HRSV in hospitalized and outpatients. Infections with Flu-A/B, and HRSV occurred shortly after the COVID-19 control measures were lifted, so a strong reoccurrence of various respiratory infections and co-detections in the post COVID-19 period was to be expected.