Tick bites and erythema migrans in eastern Austria: A large outpatient survey.

BACKGROUND: Data on tick bites and erythema migrans (EM) in eastern Austria remain limited despite ongoing changes in tick ecology. METHODS: A survey was conducted including 3005 dermatology patients in eastern Austria. Patients reported tick bites within the preceding year, subsequent EM and associated symptoms. Demographic data were collected, including age, sex, and urbanization level. Associations between tick bites, EM and demographic and geographic variables were analyzed using descriptive statistics, chi-square tests and logistic regression, including flexible spline modeling of age. RESULTS: Tick bites were reported by 430 patients (14.3%) and were more frequent in Lower Austria than in Burgenland (15.0% vs. 11.4%, p = 0.024). Tick-bite frequency was similar across urban, suburban and rural areas. Tick bites were more frequent in women (p < 0.001) and showed a significant non-linear association with age (p < 0.001). Within age groups, women aged 60 - 69 had significantly more tick bites than men in the same age group (p < 0.001). EM developed in 7% of patients following a tick bite, corresponding to approximately 1% of the entire cohort. EM was more frequent in Burgenland than in Lower Austria (11.3% vs. 6.6%, p = 0.008). CONCLUSION: Tick bites were common in this eastern Austrian outpatient cohort. The risk of being bitten varied with sex, age and region, with women more frequently affected overall. EM developed in 7% of patients with tick bites, indicating a higher manifestation index than previously reported in Austrian data. These findings support continued surveillance and targeted prevention in endemic regions.