The trends of human dirofilariasis in Croatia: Yesterday – Today – Tomorrow

INTRODUCTION: Human dirofilariasis is a disease historically linked to the Mediterranean area. For the last few decades, however, Dirofilaria nematodes have been spreading, both in terms of prevalence and the geographical expansion in non-endemic areas. Currently, cases of human dirofilariasis are recorded in more than 40 countries worldwide. Croatia is considered an endemic area of the Adriatic basin. METHODS: In a nationwide investigation, new and previously published cases of human dirofilariasis in Croatia were analyzed. RESULTS: Since 1996, 30 cases of human dirofilariosis were reported in Croatia. A total of 14 (46,67%) cases were from the coastal and 16 (53,33%) from continental regions of the country. Based on anatomical location, 13 (43,33%) cases were subcutaneous, 12 (40%) were ocular and five (16,67%) occurred in the reproductive organs. In all 30 cases, Dirofilaria repens was identified as the causative agent. CONCLUSIONS: An increase in air temperature as climate change, changes in mosquito fauna, high prevalence of D. repens in dogs and limited use of chemoprophylaxis are possible risk factors for Dirofilaria infection in the Croatian population. Since reporting to epidemiological services is not mandatory in this country, the real number of human dirofilariasis cases is probably significantly higher than published. This emphasizes the need for mandatory reporting of human cases and surveillance of Dirofilaria infection in dogs and mosquitoes in Croatia, following the “One Health” concept.