Nepropathia epidemica on the increase and spreading south in Sweden

2.086 cases of laboratory-confirmed NE were reported in Sweden during the 7-year period 1997-2003. The average age of the patients was 49,3 years and 62 per cent were men. Most cases were reported during the winter. The yearly incidence rates ranged from 1.6 cases per 100.000 in 2000 to 6.3 cases per 100.000 in 1998 varying with a 3 year cyclicity. The majority of cases were reported from the northern most counties of Sweden. The highest incidence rate was found in the county of Västerbotten (70 cases per 100.000 in 1998). However the number of cases further south seem to increase. The total number of reported cases has also increased. Comparison with previous 7-year period (1990-1996) gives an increase of 86 per cent. Handling fire-wood and hay are risk activities as well as cleaning and dusting in summerhouses.