Outcome of respiratory syncytial virus infection and a cost-benefit analysis of prophylaxis

Abstract

Objectives: To determine outcome and length of stay (LOS) for infants younger than 2 years of age admitted to hospital for respiratory syncytial virus (RSV) infection and to perform a cost-benefit analysis of prophylaxis with RSV gamma-globulin (Respigam; CSL Laboratories, Melbourne, Victoria, Australia) and monoclonal antibody (Synagis; Abbott Australasia, Kurnell, NSW, Australia) in the Australian context.

Methods: Retrospective outcome study using data from an Australian hospital and intensive care databases over a 30 month period encompassing three RSV seasons (1 May 1997-31 October 1999).

Results: The mortality for RSV infection was very low, being 0.29% of all patients admitted to hospital and 0% in infants without co-existing disease. Only 11.4% of infants required admission to the intensive care unit (ICU). Respiratory syncytial virus infection was not associated with prolonged hospitalization; patients managed in the general wards had a mean length of stay (LOS) of 4.13 days with a median of 3.0 days, while those requiring intensive care had a mean LOS of 9.8 days (including 5.1 days in the ICU). Use of RSV prophylaxis would be expected to reduce the requirement for hospital admission; however, the cost of prophylaxis is conservatively estimated to be between 7.2- and 65.3-fold the money saved in hospital care, depending on the weight of the patient and choice of drug.

Conclusions: Respiratory syncytial virus is a major cause of morbidity, but not mortality, in infants. In infants requiring hospitalization for this disease, the LOS is relatively short and the mortality extremely low. Use of prophylactic agents, which reduce the probability of hospital admission but have no effect on mortality, cannot be justified in the Australian context on cost-benefit grounds.