HRSV is one of the most important pathogens causing acute respiratory tract diseases as bronchiolitis and pneumonia among infants. HRSV was isolated from two distinct communities, a public day care center and a public hospital in São José do Rio Preto – SP, Brazil. We obtained partial sequences from G gene that were used on phylogenetic and selection pressure analysis. HRSV accounted for 29% of respiratory infections in hospitalized children and 7.7% in day care center children. On phylogenetic analysis of 60 HRSV strains, 48 (80%) clustered within or adjacent to the GA1 genotype; GA5, NA1, NA2, BA-IV and SAB1 were also observed. SJRP GA1 strains presented variations among deduced amino acids composition and lost the potential O-glycosilation site at amino acid position 295, nevertheless this resulted in an insertion of two potential O-glycosilation sites at positions 296 and 297. Furthermore, a potential O-glycosilation site insertion, at position 293, was only observed for hospital strains. Using SLAC and MEME methods, only amino acid 274 was identified to be under positive selection. This is the first report on HRSV circulation and genotypes classification derived from a day care center community in Brazil.

Respiratory syncytial virus (RSV) was detected in samples collected from children from 0 to 6 years of age with acute respiratory infection, attending public childcare on Northwest region of São Paulo, Brazil. RSV distribution was associated to seasonal climatic variables as temperature, rainfall and relative air humidity. We utilized samples of nasopharyngeal aspirate collected during the period of July 2003 to September 2005. RT-PCR was the chosen method for viral identification. Results showed that from the 817 samples (collected from 179 children), 7.7% (63/817) were RSV positive. In 2003, RSV was detected from July until October. In 2004, RSV infections occurred in March, May, June, July, October, November, and December. In 2005, RSV was detected in March, April, May, August, and September. RSV circulation patterns in childcare children showed seasonal distribution associated to decreases in temperature and relative air humidity. RSV was detected in childcare children as an important viral agent causing respiratory infections, with varying patterns of circulation into the cohort during the study period. Moreover, RSV distribution showed to be associated with the dry season on Northwest region of São Paulo, Brazil.