臺灣北部地區市售生鮮牡蠣(Crassostrea gigas)之沙門氏菌污染及抗藥特性調查

• Main Authors: 陳百勳, Chen, Pai-Hsung
• Other Authors: 臺灣大學: 獸醫學研究所, 周崇熙
• Format: Thesis
• Language: Chinese; English
• Published: 2012
• Subjects: 沙門氏菌症;整合子;基因卡匣; Salmonellosis;Integron;gene cassette; Crassostrea gigas
• Online Access: http://ntur.lib.ntu.edu.tw/handle/246246/250543; http://ntur.lib.ntu.edu.tw/bitstream/246246/250543/1/ntu-101-R97629039-1.pdf

沙門氏菌症是常見的動物產品媒介傳染病，其病原沙門氏菌廣泛存在於環境中，是全球公共衛生的重要課題，國外研究針對市售牡蠣食媒病的調查報告指出無論是市售或進口的牡蠣遭沙門氏菌污染的情形十分普遍。牡蠣在臺灣是十分受到歡迎的食材，然而對於國產或進口牡蠣中沙門氏菌的污染資料卻是欠缺。本研究即於臺灣北部地區一般傳統及超級市場調查已剝殼之國產生鮮牡蠣 (n=137) 和進口即食性生鮮牡蠣 (n=114) 共251件；其中進口牡蠣均無分離出沙門氏菌；而國產牡蠣則有80件出現沙門氏菌陽性，總分離率為58.4% (80/137)；傳統市場來源的牡蠣其分離率為58.1% (68/117)，超級市場來源的牡蠣其分離率為60% (12/20)。本次所分離出來的沙門氏菌概括11種血清型，檢出率最高的前三個血清型，分別為Saintpaul (26.4%)、Newport (21.9%) 及Infantis (13.2%)。以80件陽性樣本中所分離的91株沙門氏菌，進行藥物敏感性試驗，所分離出來的菌株對Tetracycline及Oxytetracycline的抗藥性最高 (n=12, 14.3%)。以PCR針對Integron與tet、PSE-1等抗藥基因進行檢測，檢測結果具有Integron的沙門氏菌，佔16.5%，tetA、tetB、PSE-1等基因的檢出率分別為26.4%、6.6%、22.0%。以販售型式來分，以泡水型式販賣的牡蠣污染率 (67.7%) 顯著高於非泡水型式 (50.7%) (P<0.05)；以統計方式分析菌株是否攜帶Integron與抗藥性的關係上，具Integron的菌株，其抗藥性和嵌入抗藥基因的比率上都顯著高於不具Integron的菌株；在具有tetA抗藥基因的菌株，對於Tetracycline、Oxytetracycline的抗藥性顯著高於不具tetA基因的菌株；而具有PSE-1基因的菌株，對於Ampicillin也呈現較高比例的抗藥性。根據本次研究調查顯示市售生鮮牡蠣仍具有食媒性沙門氏菌的傳播風險，其可能的汙染來源包括產地或加工過程，消費者於食材料理時仍應加強衛生習慣，以避免交叉汙染進而降低沙門氏菌的患病風險，且未來有必要進一步探究其可能之汙染來源與傳播模式。 Salmonellosis frequently causes food-borne illness in human, and poses a serious public health concern. Many of the salmonellosis outbreaks are associated with the consumption of oysters. The research about oyster in Taiwan is absent. Hence we had collect oysters from northern Taiwan’s retail market and supermarket, totally 137 samples. Import ready-to-eat oyster, totally 114 samples and screened for the presence of Salmonella. Isolates were characterized by serotyping and antibiotic resistant testing. None of imported oysters showed positive results. The domestic samples were 80 Salmonella-positive where 91 Salmonella strain were isolated and 11 Salmonella serovars were identified. The top three are Saintpaul (26.4%), Newport (21.9%) and Infantis (13.2%). The most frequent resistances were to Tetracycline and Oxytetracycline (n=12, 14.3%). The antibiotic related genes: Integron, tetA, tetB, PSE-1 were detected in 16.5%, 26.4%, 6.6%, 22% respectively. According to statistics result, the contamination level in oyster rearing location, Dongshih’s isolation rate (68.8%) is significantly higher than Budai (20.0%) and Wanggang (9.1%) (P<0.05). The presence of Salmonella isolation rate is highly associated with soaked-in-water sold type (P<0.05). The Integron-positive strains are highly associated with the presence of the antimicrobial resistance. The tetA-positive strain are highly associated with the presence of the Tetracycline and Oxytetracycline resistance. and PSE-1-positive strain are highly associated with the presence of the Ampicill in resistance. In our result shows market raw oyster are still have potential risk in foodborne disease. The hazard points include rearing enviroment and transportation procedures. Consumers should be noticed to avoid cross-infection. Further researches of contamination source and transmission route are needed.