犬瘟熱 (canine distemper ; CD) 為家犬重要的傳染性疾病之一,且家犬被認為是犬瘟熱病毒 (canine distemper virus ; CDV) 的主要保毒者,在野生動物感染CDV上扮演相當重要的角色。台灣在2005年底陸續從高雄縣桃源鄉及六龜鄉發現野生台灣鼬獾 (Melogale moschata subaurantiaca) 感染CDV死亡案例。為了解當地家犬感染CD的流行狀況以及是否具傳播CDV給野生動物之可能性,本研究於2006年9月至2008年3月針對高雄縣共12個淺山村落的家犬進行調查,總共採集了547隻家犬血清樣本和398隻全血和/或眼結膜拭子;同時也以結構式問卷訪談飼主以收集所飼養犬隻的相關資料。結果顯示當地家犬的血清盛行率為93.1%,總病原陽性率則為40.9%。另外,以RT-PCR當診斷標準時,冬季和春季感染CDV的危險性分別為夏季的5.3和5.4倍;以Indirect ELISA當診斷標準時,秋季曾經感染CDV的危險性是冬季的7.7倍,1歲以上曾經感染CDV的危險性是1歲以下的15.5倍。另外家犬主動追捕野生食肉目動物的比例為12.6%,其中以追捕鼬獾和華南鼬鼠的次數最高。本研究樣區家犬為CDV高感染率和高排毒率的地區,再加上家犬經常追捕野生動物以及所遺留在山區的排泄物,均具有一定程度的機率會傳播CDV給野生食肉目動物。建議該區家犬施打犬瘟熱疫苗,並限制其自由活動,以及減少在低溫季節的感染高峰期間到山區活動。
Canine distemper (CD) is one of the most serious infectious diseases for domestic dogs. Domestic dogs are considered a primary reservoir of the canine distemper virus (CDV) and are also a major source for wildlife infection. In 2005, CDV-caused dead wild ferret-badgers (Melogale moschata subaurantiaca) were reported from Taoyuan and Liouguei Townships, Kaohsiung Country, Taiwan. The present study was conducted between September 2006 and march 2008 for an understanding of the epidemiology of CD in domestic dogs in the area and their responsibility in the infection of CDV in wildlife populations. A total of 547 serum samples and 398 blood and / or conjunctival swabs of domestic dogs from 12 suburban villages in the area were collected during the study. Owners were also interviewed with structural questionear for collecting of related backgrounds of the dog they have. The seroprevalence of domestic dogs is 93.1%, while 40.9% dogs were CDV-positive. Result from RT-PCR showed the percentage of CDV-positive cases in winter and spring were 5.3 and 5.4 times higher than in summer, respectively, while indirect ELISA showed the percentage of antibody-positive cases in autumn was 7.7 times higher than in winter. The percentage of antibody-positive cases in dogs older than 1-year old was significant higher than in younger dogs. 12.6% dogs will hunt wild carnivores, especially ferret- badger and Himalayan weasel (Mustela sibirica). The present study showed that the domestic dog in the area has high infection rate and high excretion rate of the CDV, and their hunting behavior and activeness in wildlife habitats increased the possibility of transferring the CDV to wild carnivres. Vaccination for CD on dogs in such kind of environment is necessary, also important are the restriction of dogs’ free-ranging behaviour and avoid entering wildlife habitats during low temperature season when the infection rate of CDV is high amount domestic dogs.