The aim was to describe epidemiologic characteristics of hemorrhagic fever with renal syndrome in Croatia.
We analyzed published data from obligatory infectious disease reports and notification of deaths due to infectious diseases, data on the hemorrhagic fever with renal syndrome epidemics in Croatia, and our own data.
During the 1987-2002 period, 555 cases of hemorrhagic fever with renal syndrome were recorded in Croatia, 160 (28.8%) of them in soldiers. The mortality rate was up to 15.4% (mean 1.1%) (6/555). The highest number of cases (317) were recorded during 2002. The epidemic started in winter. The highest number of cases were recorded in June and July, i.e., during the warm season characterized by an increased activity of both animals acting as infection reservoirs and humans as hosts. The epidemic spread almost throughout Croatia. The known natural foci of hemorrhagic fever with renal syndrome are Plitvice and Slunj areas, Dinara mountain, Velika and Mala Kapela mountains, Zagreb area (Velika Gorica and Jastrebarsko), Gorski kotar area (Ogulin, Delnice), west Slavonia, and Novska area. The disease has not been recorded in the littoral area and on Adriatic Islands. The disease was also recorded in the neighboring countries of Slovenia, Bosnia and Herzegovina, Serbia and Montenegro. The identified causative agents include Dobrava and Puumala viruses of the genus Hantavirus, whereas the rodents Clethrionomys glareolus, Apodemus flavicollis, Apodemus agrarius and Apodemus sylvaticus serve as the main reservoirs of the infection in Croatia. Typical biotopes of the infection in Croatia are deciduous woods.
The 2002 epidemic confirms the presumption that almost all continental part of Croatia contains natural foci of hemorrhagic fever with renal syndrome.