栃木県足利赤十字病院における3年間（2020–2022年）のマダニ刺症49例の検討—タカサゴキララマダニ刺症40例の傾向—

During the 3-year period (2020–2022), 49 cases of tick bites were presented to the Japanese Red Cross Ashikaga Hospital in Tochigi Prefecture, Japan. More than 60% of all tick bites between March and September occurred within two months (May and June). Amblyomma testudinarium was responsible for 40 cases among all the tick bite cases. Specifically, 41 individuals of this species (39 nymphs/2 adult females) were linked (The point estimate was 0.79 with a 95% confidence interval of 0.67–1.00). There were 38 cases of tick bites in Ashikaga City, and 23 of which occurred in the vicinity of the patients’ houses (gardens and fields). Suspected cases of Tick-associated rash illness (TARI) were first recorded in the Japanese Red Cross Ashikaga Hospital in May 2020, in a total of five cases ( i.e., the patients were aged 50 years or older). TARI is indicative of repeated tick bites, which points to the permanent settlement of the A. testudinarium in and around Ashikaga City. Therefore, we believe that greater efforts should be implemented towards the detection of tick-associated infections in this area, including Severe fever with thrombocytopenia syndrome virus for which A. testudinarium is considered as a major vector.