J Tabatabai1, A Thielen2, N Lehners3, M Daeumer2, P Schnitzler4. 1. Centre for Infectious Diseases, Virology, University Hospital Heidelberg, Germany; Centre for Child and Adolescent Medicine University Hospital Heidelberg, Germany; German Centre for Infection Research (DZIF), Heidelberg, Germany. Electronic address: Julia.tabatabai@med.uni-heidelberg.de. 2. Institute of Immunology and Genetics, Kaiserslautern, Germany. 3. Department of Internal Medicine V, University Hospital Heidelberg, Germany. 4. Centre for Infectious Diseases, Virology, University Hospital Heidelberg, Germany.
Abstract
BACKGROUND: Respiratory syncytial virus (RSV) can be associated with severe disease and prolonged shedding in immunocompromised patients. OBJECTIVE: To investigate the genetic variability of RSV in consecutive samples of haematological patients with prolonged RSV shedding. STUDY DESIGN: Haematological patients at the University Hospital Heidelberg are routinely screened for respiratory viruses during winter season. In patients with prolonged RSV shedding between 2011 and 2014, Sanger-sequencing of the second hypervariable region of the RSV G gene was performed in consecutive samples. Further, deep-sequencing was performed in representative samples. RESULTS: Patients with prolonged RSV-A shedding were analysed (n=16, mean shedding 90days, 81.2% male). Phylogenetic analysis identified RSV genotypes NA1 (2011/12) or ON1 (2012/13). In most patients (n=12/16), Sanger-sequencing of the G gene showed identical sequences over the course of the shedding period. However, in two patients with particularly long viral shedding (333 and 142days), Sanger-sequencing revealed the presence of mutations leading to premature stop codons (37 and 70 amino acids truncated) in the G gene. In one additional patient, deep-sequencing revealed variants with premature stop codons at different positions. All three patients received repeatedly intravenous immunoglobulins. Interestingly, deep-sequencing revealed also a loss of the characteristic 72-nucleotide-duplication in all analysed ON1 strains. CONCLUSIONS: Long shedding periods and lack of immune selective pressure in the immunocompromised host seems to allow the persistence of viruses stripping a part of the C-terminus of the G glycoprotein. The loss of the characteristic 72-nucleotide-duplication in RSV-A ON1 variant strains is here described for the first time.
BACKGROUND:Respiratory syncytial virus (RSV) can be associated with severe disease and prolonged shedding in immunocompromised patients. OBJECTIVE: To investigate the genetic variability of RSV in consecutive samples of haematological patients with prolonged RSV shedding. STUDY DESIGN: Haematological patients at the University Hospital Heidelberg are routinely screened for respiratory viruses during winter season. In patients with prolonged RSV shedding between 2011 and 2014, Sanger-sequencing of the second hypervariable region of the RSV G gene was performed in consecutive samples. Further, deep-sequencing was performed in representative samples. RESULTS:Patients with prolonged RSV-A shedding were analysed (n=16, mean shedding 90days, 81.2% male). Phylogenetic analysis identified RSV genotypes NA1 (2011/12) or ON1 (2012/13). In most patients (n=12/16), Sanger-sequencing of the G gene showed identical sequences over the course of the shedding period. However, in two patients with particularly long viral shedding (333 and 142days), Sanger-sequencing revealed the presence of mutations leading to premature stop codons (37 and 70 amino acids truncated) in the G gene. In one additional patient, deep-sequencing revealed variants with premature stop codons at different positions. All three patients received repeatedly intravenous immunoglobulins. Interestingly, deep-sequencing revealed also a loss of the characteristic 72-nucleotide-duplication in all analysed ON1 strains. CONCLUSIONS: Long shedding periods and lack of immune selective pressure in the immunocompromised host seems to allow the persistence of viruses stripping a part of the C-terminus of the G glycoprotein. The loss of the characteristic 72-nucleotide-duplication in RSV-A ON1 variant strains is here described for the first time.