New respiratory syncytial virus epidemiology research from S. Montieri and colleagues discussed
2007 NOV 20 -- Fresh data on respiratory syncytial virus are presented in the report 'Amino acid changes in the attachment G glycoprotein of human respiratory syncytial viruses (subgroup A) isolated in Italy over several epidemics (1997-2006).' "The human respiratory syncytial virus (HRSV) is the most important cause of admission to hospital for acute lower respiratory tract infections in infants and young children worldwide. Only few studies have investigated the molecular evolution of HRSV, and none has been conduct ed in Italy," researchers in Rome, Italy report. "The genetic diversity of the G glycoprotein of 59 subgroup A strains obtained from two clinical centers located in Northern and Central Italy was studied, during seven nonconsecutive epidemic seasons (1997-2006). The nucleotide sequences encompassing 624 bp, at the carboxy terminus of the G glycoprotein gene, were compared to sequences representative of previously defined HRSV genotypes. Phylogenetic analysis indicated that most Italian group A isolates clustered into two different lineages (GA2 and GA5), whereas only few isolates grouped into the other known lineages. Eight positively selected sites were found and it was predicted that serine and threonine of positively selected sites 117 and 262 (respectively) are O-glycosilated. The presence of multiple identical sequences in three lineages (GA1, GA5, and BE/A1) suggests that certain strains are predominant in a given epidemic season. Although most of the sites of the G glycoprotein gene of HRSV-A strains seem invariable because of strong purifying selection, some evolutionary 'hot spots' may be present," wrote S. Montieri and colleagues, . The researchers concluded: "Since the G glycoprotein is a major target (together with the F glycoprotein) of the HRSV humoral immune response, it is important to provide information about its genetic heterogeneity in order to address better both therapeutic and vaccine strategy." Montieri and colleagues published their study in the Journal of Medical Virology (Amino acid changes in the attachment G glycoprotein of human respiratory syncytial viruses (subgroup A) isolated in Italy over several epidemics (1997-2006). Journal of Medical Virology, 2007;79(12):1935-42). For additional information, contact S. Montieri, Parasitic and Immunomediated Diseases, Dept. of Infectious, Istituto Superiore di Sanita, Rome, Italy. Publisher contact information for the Journal of Medical Virology is: Wiley-Liss, Division John Wiley & Sons Inc., 111 River St., Hoboken, NJ 07030, USA. Keywords: Italy, Rome, Respiratory Syncytial Virus Epidemiology, Epidemiology, Immunization, Infectious Disease, Pulmonology, Respiratory Syncytial Virus, Viral, Virology. This article was prepared by Health Risk Factor Week editors from staff and other reports. Copyright 2007, Health Risk Factor Week via NewsRx.com.
|
