Phylogenetic Analysis of Respiratory Syncytial Virus Isolated from Children with Acute Respiratory Inflammation in One Pediatric Outpatient Clinic in Okinawa

We investigated respiratory syncytial virus in children with acute respiratory disease at one pediatrics clinic in Okinawa from June to December 2008. RSV was detected in 14(23.3%) of 60 clinical specimens by RT-PCR, and 8 RSV isolates were isolated by cell culture. Phylogenetic analysis showed that 7 of the 8 new isolates were classified into genotype GA2 within subgroup A, and one into genotype BA within subgroup B. These Okinawa isolates were genetically related with not only the recent Japanese isolates but also the distant countries’ isolates such as Brazil, Belgium and India. These results suggested that different RSV genotypes circulate in an epidemic period and that RSV spreads rapidly worldwide, as described previously. In addition, this study suggests that the difference of the prevalent season of RSV infection between Okinawa and other area of Japan may not be dependent on the aspects of strain.