[Infection surveillance in North Rhine-Westphalia--standard reports, barometer and early warning system]

The increasing significance of communicable diseases requires new surveillance tools. Modern electronic instruments in analysis and communication replace the former "handbased" statistics and allow the development of early warning systems. In North Rhine-Westphalia (NRW) the Institute of Public Health started an approach to develop a modular surveillance system prior to the the implementation of the new German infectious disease protection act. The first module called "Automated infectious disease notifications and information system (AIM+)" generates various standard hypertext reports which are published as "Infectious disease reports NRW" on the internet (www.loegd.nrw.de). In addition the infectious disease information is linked with a geographical information system (GIS) giving spatial and temporal patterns. The second module called "Infectious disease barometer NRW" offers a quick actual overview highlighting several selected diseases. It can be electronically sent out to any interested person. The third module "Early warning system" realizes an effective early detection system by combining six statistical procedures with a total of 11 separate methods. In case of detecting clusters and outbreaks it automatically generates warning reports to the responsible parties. All three modules together improve the epidemiological surveillance of the population in NRW, support the translation of information to prevention and control measures, and therefore strengthen epidemiological policy-making.