Overview of Respiratory Syncytial Virus (RSV)
Impact on Young Children
Respiratory syncytial virus (RSV) stands as the most prevalent virus responsible for acute lower respiratory infections in young children. A recent comprehensive review has updated the global impact of RSV, providing crucial insights that can shape future vaccine development and implementation policies.
Acute Lower Respiratory Tract Infections
Acute lower respiratory tract infections (ALRI), typically manifesting as pneumonia or bronchiolitis, rank among the leading causes of illness and mortality in children under five years old. RSV is identified as the primary virus linked to these infections in this age group. Previous estimates indicated that in 2005, approximately 33.8 million new RSV-related lower respiratory infections occurred worldwide among young children, with about 10% requiring hospitalization. Furthermore, RSV accounted for 22% of severe lower respiratory infection episodes, resulting in an estimated 55,000 to 199,000 deaths in children under five.
Recent Developments and Vaccination Efforts
Vaccine Potential
The WHO Vaccine Advisory Committee has identified RSV as a promising area for new vaccine development, with potential availability within the next 5 to 10 years. A review of 329 studies revealed that 291 were not included in earlier RSV data estimates. This comprehensive analysis estimated that in 2015, there were 33.1 million episodes of RSV-related ALRI globally, leading to around 3.2 million hospital admissions and approximately 59,600 in-hospital deaths in children under five.
Mortality Rates in Young Children
Among infants younger than six months, RSV-ALRI was responsible for 1.4 million hospital admissions and 27,300 in-hospital deaths. The overall mortality associated with RSV-ALRI could reach as high as 118,200, although incidence and mortality rates varied significantly across different populations studied.
Current Vaccine Development
RSV remains a significant cause of lower respiratory infections and a leading reason for hospital admissions in young children. Currently, over 60 potential RSV vaccines are under development, targeting various demographics including pregnant women and infants. These global incidence estimates of RSV are vital for guiding vaccination development and shaping implementation policies.
Reference
Shi T, McAllister DA, O’Brien K, et al. Global, regional, and national disease burden estimates of acute lower respiratory infections due to respiratory syncytial virus in young children in 2015: A systematic review and modelling study. The Lancet. Published online July 6, 2017. http://dx.doi.org/10.1016/S0140-6736(17)30938-8.