Tick-borne diseases in the Republic of Croatia

This study analyses occurence, trendline, occurence by months and geographical distribution of tick-transmitted diseases: Lyme borreliosis, Tick-borne meningoencephalitis (TBM) and Mediterranean spotted fever in the Republic of Croatia in the period between 1999 and 2008. The vector for Lyme borreliosis and tick-borne meningoencephalitis is Ixodes ricinus, while Mediterranean spotted fever is transmitted by the Rhipicephalus sanguineus. Lyme disease is endemic in entire continental Croatia and Croatian littoral. Tick-borne meningoencephalitis is endemic in northern Croatia. Mediterranean spotted fever occurs only in Dalmatian counties and the average annual incidence rate increases from north to south of Dalmatia. All three diseases show extremely seasonal characteristics, which is conditioned by the biological cycle of ticks as their activity peaks in summer and spring. In terms of vaccines against the above diseases, the only one available in Croatia is the TBM vaccine and it is applied according to epidemiological indications. In preventing Lyme disease some authors have recommended a single 200-mg dose of doxycycline taken within 72 hours of being bitten by an infected tick.