Unravelling respiratory syncytial virus outbreaks in Buenos Aires, Argentina: Molecular basis of the spatio-temporal transmission.

Respiratory syncytial virus (RSV) is the main viral cause of hospitalization due to acute lower respiratory tract infections in infants worldwide. Several vaccines against RSV are under research and development, which are about to be approved. We evaluated transmission patterns in different settings to determine age-specific vaccination targets from a viral perspective. We sequenced the G glycoprotein's ectodomain of a constant clinical sampling between two epidemic outbreaks in a limited geographical region and performed phylogeographic analyses. We described a spatio-temporal transmission between local strains, which were originated in the center of the analyzed area and then spread to others. Interestingly, that central area reported the highest population density of the region and also showed overcrowding. This information should be considered by public health systems to evaluate vaccination at all ages in those areas to decrease viral transmission and in lower density populations only susceptible children should be vaccinated.