Genetic variability of human respiratory syncytial virus in Pune, Western India.
ABSTRACT Human respiratory syncytial virus (RSV) is one of the most important respiratory viruses causing acute respiratory tract infections amongst children. Based on genotyping of the attachment glycoprotein (G) gene, it is divided into two groups, RSV-A and RSV-B. Infection with one group does not confer immunity against the other and children infected with one antigenic group are more likely to be reinfected with the heterologous group. We tested 854 samples of patients with influenza like illness (ILI)/ severe respiratory illness (SARI) during the period 2009-2012 for RSV using a conventional multiplex RT-PCR and found 159 (18.61%) samples to be positive for RSV of which 130 (15.22%) were positive for RSV-B and 29 (3.39%) for RSV-A suggesting that RSV-B was the predominant group circulating in western India during the study period. Seasonal RSV outbreaks were observed in the monsoon and winter months. RSV was more prevalent amongst children in the 0-24 month age group (21.53%) in comparison to children in the 24-60 month age group (13.01%). Phylogenetic analysis using the G gene of 27 representative RSV-A positive samples revealed that all sequences belonged to the NA1 genotype. Of these, 5 sequences exhibited the novel 72 nucleotide duplication in the C-terminal of the G gene first reported from Ontario, Canada and clustered in the newly designated ON1 genotype. Also, 32 of the 33 RSV-B sequences exhibited the 60 nucleotide duplication associated with genotype BA and phylogenetic analysis showed that these sequences belonged to the genotype BA9 and BA12. We also found one RSV-B sequence belonging to genotype GB2, which has not been previously reported in India.
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ABSTRACT: Respiratory syncytial virus (RSV) is an important respiratory pathogen in infants and children worldwide. Although RSV typically causes mild upper respiratory infections, it frequently causes severe morbidity and mortality, especially in premature infants and children with other chronic diseases. Treatment of RSV is limited by a lack of effective antiviral treatments; however, ribavirin has been used in complicated cases, along with the addition of intravenous immune globulin in specific patients. Vaccination strategies for RSV prevention are heavily studied, but only palivizumab (Synagis(®)) has been approved for use in the United States in very select patient populations. Research is ongoing in developing additional vaccines, along with alternative therapies that may help prevent or decrease the severity of RSV infections in infants and children. To date, we have not seen a decrement in RSV morbidity and mortality with our current options; therefore, there is a clear need for novel RSV preventative and therapeutic strategies. In this review, we discuss the current and evolving trends in RSV treatment for infants and children.ClinicoEconomics and Outcomes Research 01/2014; 6:217-225.