Sequential Delivery of Live Attenuated Influenza Vaccine and Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) in the Ferret Model Can Reduce SARS-CoV-2 Shedding and Does Not Result in Enhanced Lung Pathology

• Published in: The Journal of infectious diseases Vol. 225; no. 3; pp. 404 - 412
• Main Authors: Ryan, Kathryn A, Schewe, Katarzyna E, Crowe, Jonathan, Fotheringham, Susan A, Hall, Yper, Humphreys, Richard, Marriott, Anthony C, Paterson, Jemma, Rayner, Emma, Salguero, Francisco J, Watson, Robert J, Whittaker, Catherine J, Carroll, Miles W, Dibben, Oliver
• Format: Journal Article
• Language: English
• Published: US Oxford University Press 01.02.2022
• Subjects: Animals; Coronaviruses; COVID-19 - therapy; COVID-19 vaccines; Disease Models, Animal; Ferrets; Infections; Influenza; Influenza Vaccines - therapeutic use; Lung; Lung diseases; Pathology; Respiratory System - virology; Respiratory tract; SARS-CoV-2 - physiology; Severe acute respiratory syndrome coronavirus 2; Vaccines; Vaccines, Attenuated - therapeutic use; Virus Replication; Virus Shedding; COVID-19; live attenuated influenza vaccine; LAIV; SARS-CoV-2; coinfection; ferret
• ISSN: 0022-1899; 1537-6613
• DOI: 10.1093/infdis/jiab594

Abstract Cocirculation of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and influenza viruses could pose unpredictable risks to health systems globally, with recent studies suggesting more severe disease outcomes in coinfected patients. The initial lack of a readily available coronavirus disease 2019 (COVID-19) vaccine has reinforced the importance of influenza vaccine programs during the COVID-19 pandemic. Live attenuated influenza vaccine (LAIV) is an important tool in protecting against influenza, particularly in children. However, it is unknown whether LAIV administration influences the outcomes of acute SARS-CoV-2 infection or disease. To investigate this, quadrivalent LAIV was administered to ferrets 3 days before or after SARS-CoV-2 infection. LAIV administration did not exacerbate the SARS-CoV-2 disease course or lung pathology with either regimen. In addition, LAIV administered before SARS-CoV-2 infection significantly reduced SARS-CoV-2 replication and shedding in the upper respiratory tract. This study demonstrated that LAIV administration in close proximity to SARS-CoV-2 infection does not exacerbate mild disease and can reduce SARS-CoV-2 shedding. Live attenuated influenza vaccine (LAIV) administration in proximity to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection was investigated in ferrets. Vaccination did not exacerbate mild coronavirus disease 2019 (COVID-19) and, if delivered before challenge, reduced SARS-CoV-2 shedding. This supports safe LAIV administration during the COVID-19 pandemic, with potential to reduce SARS-CoV-2 transmission.