Importance of global surveillance for respiratory syncytial virus.

This supplement of the Journal provides a compendium of epidemiologic, clinical, and laboratory data to address gaps in knowledge regarding acute respiratory illness associated with respiratory syncytial virus (RSV) in countries participating in the International Emerging Infections Program and the Influenza Program of the Global Disease Detection (GDD) network of the US Centers for Disease Control and Prevention, Center for Global Health. The GDD network is described in the supplement review articles by Breiman et al and Fields et al. Six GDD Centers (in China, Guatemala, Egypt, Kenya, South Africa, and Thailand) present supplement articles about children and adults with community-acquired RSV infection confirmed by sensitive real-time reverse-transcription polymerase chain reaction (RT-PCR) assays during recent years of active, prospective, population-based surveillance for acute respiratory illness and severe lower respiratory tract infections; a seventh GDD Center, in Bangladesh, provided RSV seasonality data. These countries are classified as lowand middle-income economies by the World Bank and include populations considered at high risk for infectious diseases, including urban poor, rural, and human immunodeficiency virus (HIV)–infected persons. The GDD data underscore the need to develop public health and preventive strategies to mitigate the influence of RSV worldwide. RSV is an enveloped RNA virus with surface proteins that mediate RSV infection of human airway epithelial cells. RSV strains are classified into genotypes within 2 major RSV subgroups, RSV-A and RSV-B. RSV is the leading viral cause of acute lower respiratory tract infections, including bronchiolitis and pneumonia, among infants and young children globally. Resourceconstrained populations bear the largest burden of severe RSV disease, accounting for 91% of 2.8–4.3 million hospitalizations and 99% of 66 000–199 000 deaths among children aged <5 years in 2005, based on a global metaanalysis by Nair et al [1]. The study by Nair et al also noted that, although RSV-associated mortality data were scarce, almost all RSV-associated deaths reported from high-income countries occurred among children aged <1 year, whereas RSV deaths in developing countries also occurred among children during their second year of life. The burden of severe RSV disease is likely underrecognized because of the limited number of population-based studies from developing countries, the challenges in capturing non–medically attended cases of RSV infection in the community, and the scarcity of data on laboratoryconfirmed RSV-associated deaths. Our understanding of the etiology of acute respiratory illness will be enhanced by the increasing capacity for multipathogen testing. GDD Center laboratories test specimens for multiple respiratory viruses, thus providing opportunities to assess the impact of real-time RT-PCR–confirmed RSV. In addition to estimating the age-specific incidence of RSV-associated hospitalization, 2 GDD Centers provided data for this supplement on outpatient visits for RSV-associated illness, and the Kenya site identified cases through household-level community-based surveillance for respiratory disease. Several GDD Centers conducted healthcare utilization surveys to determine patterns of healthcare-seeking behavior for acute Correspondence: Marika K. Iwane, PhD, MPH, Centers for Disease Control and Prevention, National Center for Immunization and Respiratory Diseases, 1600 Clifton Rd, NE, MS A-34, Atlanta, GA 30333 ([email protected]). The Journal of Infectious Diseases 2013;208(S3):S165–6 Published by Oxford University Press on behalf of the Infectious Diseases Society of America 2013. This work is written by (a) US Government employee(s) and is in the public domain in the US. DOI: 10.1093/infdis/jit484