Human Anti-RSV pre-fusion conformation of HRSV F protein monoclonal antibody, clone STC30

Background: Respiratory syncytial virus is the main cause of acute respiratory infections leading to a considerable morbidity and mortality among under-5 years children. A comprehensive scheme of RSV virus evolution is of great value in implementing effective universal RSV vaccine. Objective: We investigated the clinical spectrum and molecular characteristics of detected RSV over a period of seven years (January 2011 to June 2017) in Antananarivo, the capital city of Madagascar. Study design: 671 nasopharyngeal samples taken from children aged less than 5 years suffered from ARI were screened for RSV by real-time PCR. Clinical data were retrieved from case report forms. Genotype identification was performed by reverse-transcription PCR and sequencing of the second hyper variable region (HVR2) of the G glycoprotein. Results: Amongst samples tested, 292 (43.5 %) were found positive for RSV. RSV A predominated during the study period which accounted for 62.3 % (182/292) of positive samples while RSV B represented 37.0 % (108/292). Phylogenetic analyses identified NA1 and ON1 genotypes among RSV A. Though NA1 widespread from 2011 to 2013, ON1 became prevalent during the following years. Among RSV B, THB, CB1 and BA9 genotypes were detected. A co-circulation of THB and CB1 strains occurred during the 2011 season that was substituted by the BA9 from 2012. Malagasy ON1 strains carried some characteristic amino acid substitutions that distinguish them from the worldwide ON1 strains. By analyzing clinical spectrum, ON1 and BA genotypes seemed to prevail in mild infections compared to NA1. Conclusion: Results obtained here will have its implication in predicting temporal evolution of RSV at the local level. Considering the insularity of the country, information obtained should help in comparative analysis with global RSV strains to optimize vaccine efficacy.

Respiratory viral infections are known causes of mortality after allogeneic hematopoietic stem cell transplantation (HSCT). Here, we report a unique case of a child with viral pneumonia caused by coinfection with human metapneumovirus (MPV), respiratory syncytial virus (RSV), and SARS-CoV-2 after HSCT. A 9-year-old girl with acute lymphoblastic leukemia underwent allogeneic HSCT from a matched, unrelated donor. During the post-transplant period, in profound leukopenia (below 10 leukocytes/mu L), she was diagnosed with SARS-CoV-2, MPV, and RSV pneumonia and was treated with ribavirin and chloroquine. Before leukocyte recovery, the girl became asymptomatic, and SARS-CoV-2 and RSV clearance was achieved. The shedding of SARS-CoV-2 stopped before immune system recovery, and one may hypothesize that the lack of an inflammatory response might have been a contributing factor to the mild clinical course. Post-transplant care in HSCT recipients with COVID-19 infection is feasible in regular transplant units, provided the patient does not present with respiratory failure. Early and repeated testing for SARS-CoV-2 in post-transplant patients with concomitant infection mitigation strategies should be considered in children after HSCT who develop fever, respiratory symptoms, and perhaps gastrointestinal symptoms to control the spread of COVID-19 both in patients and in healthcare workers in hospital environments. Training of staff and the availability of personal protective equipment are crucial for containing SARS-CoV-2 infection.