弓蟲感染非常普遍，在經濟及公共衛生上很重要。為了提供基本的數據做為臺北市流浪犬弓蟲症之流行病學研究，本調查以kinetics-based enzyme-linked immunosorbent assay 合併immunoblotting偵測弓蟲IgG及IgM血清抗體盛行率。Immunoblotting 可以檢測出弓蟲特異性30kD表面抗原。結果顯示整體弓蟲抗體的血清陽性率為8% (n=100)，而95%confidence interval為(0.0352, 0.152)。IgG及IgM抗體盛行率分別為6%及3%，然而此差異統計上並不顯著(McNemar’s test, P=0.0898)。只有少數的流浪犬為活動性弓蟲感染(即IgM陽性)。弓蟲抗體盛行率在雄犬為11.4% (n=44)，而在雌犬為5.4% (n=56)。抗體盛行率和性別無關(Fisher’s exact test, P=0.2951) ; Toxplasma gondii infection is widespread and is of economic as well as public health importance. To provide the basic data necessary for studying the epidemiology of toxoplasmosis in stray dogs in Taipei, the seroprevalences of IgG and IgM antibodies to T. gondii were measured using a kinetics-based enzyme-linked immunosorbent assay in conjunction with immunoblotting. Immunoblotting is able to detect the presence of antibody to T. gondii-specific 30 KD-surface antigen. The results showed that total seropositivity was 8% (n=100) with a 95% confidence interval of (0.0352, 0.152). The prevalences of IgG and IgM antibody to T. gondii were 6% and 3% respectively. Nevertheless, this difference was not statistically significant (McNemar’s TEST, P=0.0898). Only a small number of stray dogs had active T. gondii infection (IgM positive). The prevalences of T. gondii antibody were 11.4% (n=44) for males and 5.4% (n=56) for females. Antibody prevalence was not sex-dependent (Fisher’s exact test, P=0.2951).