Background: Passive immunization with palivizumab is expensive and requires considerable logistic effort. So far 5 monthly injections from November to March are recommended. The RSV season onset and its duration, however, shows considerable variation. In many countries on the northern hemisphere a dual rhythm is described.
Method: A web-based early warning system within the research network PID-ARI.net is in place since 2002. The surveillance data are published online weekly via www.pid-ari.net. This enables physicians to carry out interventions, like passive immunization for RSV, synchronously with the epidemiology of a given pathogen instead of a rigid schedule. The surveillance of PID-ARI.net is based on a 19 valent multiplex RT-PCR on naso-pharyngeal aspirates. The samples are provided by hospitals and offices in Freiburg, Mainz and Schleswig-Holstein (north, middle, south of Germany). Children with lower airway infections are prospectively enrolled.
Results: In the time period from July 1999 to June 2003 with 20 months of recommended palivizumab application, 5 months (25 %) would have been not on target. In two seasons the start of the vaccine campaign would have been too early (waste of two months). In one season the application would have started one month too late and in two seasons the vaccine campaign would have been stopped two months too early leaving the vaccinees on risk for acquiring RSV.
Conclusions: The web-based early warning system of PID-ARI.net is the first, pathogen-specific, comprehensive and fast surveillance-system for airway pathogens in Europe. It facilitates the epidemic-synchronous use of the passive immunization with palivizumab and by this increases its efficiency and should safe costs.