Recent advances in sensor technologies, wireless communication, powerful mobile devices, and wearable computers strongly support novel types of applications. Especially in healthcare, telemonitoring applications will make use of this new technology to improve the quality of treatment and care for patients and the elderly. These telemonitoring applications require an infrastructure that is able to efficiently combine, process, and manage continuous streams of data coming from the different sensors. In healthcare where applications can be life saving, a particularly important requirement is that this infrastructure is highly reliable. In this paper, we introduce OSIRIS-SE, a novel information management infrastructure for data stream processing based on the hyperdatabase OSIRIS that features a high degree of reliability.