Identification of group B respiratory syncytial viruses that lack the 60‐nucleotide duplication after six consecutive epidemics of total BA dominance at coastal Kenya

Charles N Agoti,D James Nokes,Graham F Medley,Caroline W Gitahi,Patricia A Cane

doi:10.1111/irv.12131

Abstract

Respiratory syncytial virus BA genotype has reportedly replaced other group B genotypes worldwide. We report the observation of three group B viruses, all identical in G sequence but lacking the BA duplication, at a coastal district hospital in Kenya in early 2012. This follows a period of six consecutive respiratory syncytial virus (RSV) epidemics with 100% BA dominance among group B isolates. The new strains appear only distantly related to BA variants and to previously circulating SAB1 viruses last seen in the district in 2005, suggesting that they were circulating elsewhere undetected. These results are of relevance to an understanding of RSV persistence.

Highlights

Human respiratory syncytial virus (RSV) is the leading viral cause of acute lower respiratory tract illnesses in infants and young children worldwide[1] and is associated with annual or biannual epidemics.[2]
RSV repeatedly re-infects individuals throughout life, and the strains involved are often genetically distinct.[4]. The differences occurring both between and within the groups are most pronounced at the attachment (G) protein gene, which encodes a surface-expressed protein of the virus known to be targeted by the host neutralizing antibody response.[1]
Over the period January 1, 2002, to June 31, 2012, 574 group B RSVs were identified among the RSV IFAT-positive samples, and 488 (85Á0%) of these were successfully sequenced in the G ectodomain region

Summary

Introduction

Human respiratory syncytial virus (RSV) is the leading viral cause of acute lower respiratory tract illnesses in infants and young children worldwide[1] and is associated with annual or biannual epidemics.[2]. Group B RSVs that we identified over the 11 years of the surveillance, and the results of analysis of novel non-BA strains we observed in three patients infected in early 2012.

Results

Conclusion