Regional impact of prophylaxis with the monoclonal antibody palivizumab on hospitalisations for respiratory syncytial virus in infants.
OBJECTIVE
Palivizumab is approved in Switzerland for prevention of hospitalisation for RSV infection in children with one of the following risk factors: (1) history of prematurity < or = 35 weeks and age < or = 6 months or (2) chronic lung disease and age < or = 1 year. Regional data on the expected effectiveness of this monoclonal antibody are not available.


METHODS
(1) Retrospective, descriptive, single-site study on the characteristics of RSV hospitalisations during two consecutive seasons. (2) Extrapolation of data to generate population-based estimates on the impact of palivizumb if used according to the approved indications.


RESULTS
Of 242 RSV hospitalisations, 216 (89.3%) and 26 (10.7%) occurred in children without and with risk factors, respectively. Patients without and with risk factors had similar clinical courses with respect to ICU admission rate (11.6 vs. 11.5%) and rate of mechanical ventilation (3.2 vs. 3.8%). Of a total of 28 ICU admissions, 13 (46%) occurred among infants aged < or = 1 month without risk factors. Former premature infants were significantly older than patients with longer gestation (median age 7.5 vs. 3.7 months, p = 0.026). Applying the approved age criteria would have excluded 10 of 26 patients (38.5%) from eligibility for palivizumab. During the 1999/2000 RSV season, 36% of hospitalisations occurred after April 1, 2000. None of them may have been preventable had prophylaxis been started before November 1, 1999 and carried out for 5 months as recommended. In an annual birth cohort of 10,000, palivizumab as indicated would be expected to prevent between 5 and 7 RSV hospitalisations.


CONCLUSIONS
The impact of palivizumab on the prevention of RSV hospitalisations in the Canton of Bern, Switerland, is expected to be small, and the approved indications may not target infants at greatest risk for severe disease.
Duppenthaler
A
A
Department of Paediatrics and Institute for Infectious Diseases, University of Bern, Switzerland.
Gorgievski-Hrisoho
M
M
Aebi
C
C
D000911:Antibodies, Monoclonal / Q000191:economics / Q000627:therapeutic use*; D061067:Antibodies, Monoclonal, Humanized; D000998:Antiviral Agents / Q000191:economics / Q000627:therapeutic use*; D003362:Cost-Benefit Analysis; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007234:Infant, Premature; D008297:Male; D000069455:Palivizumab; D018357:Respiratory Syncytial Virus Infections / Q000453:epidemiology / Q000517:prevention & control*; D012189:Retrospective Studies; D012307:Risk Factors; D018709:Statistics, Nonparametric; D013557:Switzerland / Q000453:epidemiology; D016896:Treatment Outcome
D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D000998:Antiviral Agents; D000069455:Palivizumab