Respiratory syncytial virus (RSV)

Human RSV (hRSV) is the predominant aetiological agent of respiratory infection resulting in hospitalisation of children under six months of age worldwide. hRSV infection occurs in annual epidemics in the winter months in temperate climates and in the UK an average of almost 11,000 children are diagnosed as suffering from hRSV infection following hospital admission with acute respiratory disease each year. This has significant consequences for seasonal demand for acute paediatric care facilities. Recent studies have shown that hRSV infection in the elderly is also a significant health burden and can be life threatening. hRSV also infects the general population during annual epidemics and in healthy adults the infection leads to respiratory disease which although usually confined to the upper respiratory tract, can also spread to the lower respiratory tract generating more severe symptoms of disease. Approximately 1% to 3% of hospitalised children in developed countries die as a result of hRSV infection. The children for whom infection is fatal generally have an additional underlying problem such as congenital heart disease. In developing countries the mortality rate is higher due to additional factors, including malnutrition. Following an initial infection in the first few years of life, no long-lived immunity is acquired with the consequence that re-infection occurs frequently. While the severity of infection in middle years is considered not to be life-threatening, infection is regarded as a serious clinical problem in geriatric patients.

Despite its clinical importance opportunities for prophylactic or therapeutic intervention for hRSV infection are limited in number and efficacy. The use of ribavirin has been approved for treatment of hRSV infection in infants but its efficacy is at best minimal. Prophylactic intravenous or intramuscular administration of polyclonal (Respigam^®) or monoclonal (Synagis^®) antibodies, respectively, has been shown to provide some level of reduction in the incidence and duration of hRSV hospitalization and the severity of hRSV illness in high risk infants. These treatments are restricted to high risk individuals primarily due to the high cost. However, there is no widely available vaccine or treatment available for prevention of hRSV disease.

We are using the technique of reverse genetics to study key regulatory features of the molecular biology of RSV.