Distinct patterns of within-host virus populations between two subgroups of human respiratory syncytial virus.
Lin G-L., Drysdale SB., Snape MD., O'Connor D., Brown A., MacIntyre-Cockett G., Mellado-Gomez E., de Cesare M., Bonsall D., Ansari MA., Öner D., Aerssens J., Butler C., Bont L., Openshaw P., Martinón-Torres F., Nair H., Bowden R., RESCEU Investigators None., Golubchik T., Pollard AJ.
Human respiratory syncytial virus (RSV) is a major cause of lower respiratory tract infection in young children globally, but little is known about within-host RSV diversity. Here, we characterised within-host RSV populations using deep-sequencing data from 319 nasopharyngeal swabs collected during 2017-2020. RSV-B had lower consensus diversity than RSV-A at the population level, while exhibiting greater within-host diversity. Two RSV-B consensus sequences had an amino acid alteration (K68N) in the fusion (F) protein, which has been associated with reduced susceptibility to nirsevimab (MEDI8897), a novel RSV monoclonal antibody under development. In addition, several minor variants were identified in the antigenic sites of the F protein, one of which may confer resistance to palivizumab, the only licensed RSV monoclonal antibody. The differences in within-host virus populations emphasise the importance of monitoring for vaccine efficacy and may help to explain the different prevalences of monoclonal antibody-escape mutants between the two subgroups.