Epidemiological surveillance of Guillain-Barre syndrome in Sweden, 1996-1997

Objectives - To set up an epidemiological surveillance system of Guillain-Barre syndrome (GBS) in Sweden and to evaluate the pilot practice of the system for 2 years. Material and methods - A network of neurologists reported incident patients with a GBS diagnosis among a general population of 4.5 million inhabitants in Sweden during 1996-1997. Historical GBS data from the national hospital in-patient registry were used for predicting incidences and controlling under-reporting. Results - One hundred and seventeen cases were reported. No alarm signals were identified during the study period. A re-analysis of data in 1996 revealed: 1) a higher than expected incidence in the population aged below 40 years in January, and 2) 27% under-reporting mainly associated to one hospital and to GBS patients hospitalized outside neurological departments. Threshold values for GBS incidences among the general and selected populations were obtained from corrected data. Conclusion - The Swedish Network for GBS Surveillance can provide immediate support for epidemiological evaluation of suspected outbreaks or increased GBS incidence.