Of 263 patients in Tuscany, Italy, from whom ticks were removed during July 2005-May 2007, fi ve showed signs of tick-borne lymphadenopathy. Of the ticks, 17 were Dermacentor marginatus; 6 (35.3%) of these were identifi ed by sequence analysis as containing Rickettsia slovaca. Tickborne lymphadenopathy occurs in this area. R ickettsia slovaca was fi rst isolated in Czechoslovakia from the tick vector Dermacentor marginatus in 1968 (1) and was subsequently detected in several European countries. It was recognized as the causative agent of tick-borne lymphadenopathy (2-4) and Dermacentor spp.-borne necrosis-erythema-lymphadenopathy (5). Typical clinical signs of infection include skin lesions at the tick bite site and regional, often painful, lymphadenopathy (2,3). Acute disease can be followed by residual alopecia at the bite site (2). This disease is considered a mild rickettsiosis, but severe symptoms have been described, especially in untreated patients (2).D. marginatus is the only member of the species Dermacentor reported in Italy; it is widely distributed in prairies and steppes up to 2,500 m above sea level, including the northern Apennines (6). Adults are active within a temperature range of 4°C to 16°C (7,8). Temperature infl uences the seasonality of tick-borne lymphadenopathy, which has a higher incidence during cold months (4,9). We describe results from a tick-borne zoonoses surveillance system that was implemented in 2002 at the Lucca local health unit (ASL 2) in Tuscany, Italy.
The StudyPatients admitted to emergency units in Tuscany, Italy, for tick removal were followed up for 40 days. Epidemiologic and clinical data were collected for each patient by using a standardized questionnaire. History of allergic reactions or hypersensitivity to tick bites was considered and evaluated to avoid mistakes in case defi nition.Ticks were classifi ed by using standard identifi cation keys (8) and stored in 70% ethanol until DNA extraction. D. marginatus females were measured, and the degree of engorgement (tick engorgement index [TEI]) was visually estimated. Ticks were ranked by 3 TEI levels: 1 = completely unengorged, 2 = intermediate (idiosoma length ≈2× twice the scutum width), and 3 = engorged (idiosoma length >2× the scutum width). Association between TEI levels and occurrence of clinical symptoms was evaluated by using the Fisher exact test. All statistical analyses were conducted by using R statistical software (10). Arcview 3.3 (Environmental Systems Research Institute Inc., Redlands, CA, USA) was used to map the geographic distribution of cases in the study area (Figure 1).For pathogen detection by PCR, ticks were individually homogenized with a pestle in microcentrifuge tubes and DNA was extracted with the DNeasy Blood and Tissue Kit (QIAGEN, Hilden, Germany). Negative controls (distilled water) were used to check for contamination of samples during this phase. Success of DNA extraction was verifi ed by using PCR for tick mitochondrial 16S rDNA (11). Two PCR assays, targeting citrate synthase A (g...