金黄色葡萄球菌及其引起的食物中毒的研究进展

金黄色葡萄球菌广泛存在于自然环境中,致病力强,是常见食物中毒的病原菌。本文对金黄色葡萄球菌致病因素、污染状况、食物中毒、试验诊断、预防措施等方面进行概述,为今后金黄色葡萄球菌食物中毒的预防提供参考。     

暑期慎防食物中毒

每年进入暑期，食物中毒的现象都经常发生。那么，食物中毒是怎么回事？如何避免食物中毒的发生呢？一旦发生食物中毒，又该如何正确处理呢？ 食物中毒通常指令用了含有某种毒素的食物，而引起的急性中毒症状。其原因可分为细菌性和非细菌性两种。     

Bacteria and food poisoning organisms in milk

Individual milk samples of 50 goats, 50 ewes and 50 cows were examined for the total viable count, coliform bacteria, staphylococci and salmonellae. Growth of enterotoxin A producing Staphylococcus aureus NCTC 10 652 in the milk of the three animal species was also studied. The average total count was 1.9 × 10⁷ cells/ml for cow's, 7.7 × 10⁶ for goat's and 2.7 × 10⁶ for ewe's milk with micrococci staphylococci, rods and streptococci being the predominant organisms in the three milks, respectively. Goat's milk contained the lowest numbers of coliforms and ewe's milk the highest numbers. Staphylococcus aureus could not be detected in goat's milk, whilst 16 and 26% of the ewe's and cow's milk samples contained 100 and 80 cells/ml, respectively. Out of 39 coagulase positive staphylococci, 27 were thermonuclease positive, 18 produced lecithinase and 15 fermented mannitol. Red blood cells of sheep origin were much more resistant to lysis by ewe's strains compared to bovine strains. Growth curves of Staphylococcus aureus were nearly linear at 17°C but exponential at 31°C without lag phase. Hazardous numbers of about 10⁶ cells/ml were readily reached at 31°C after 6 h and at 17°C after 18 h. Salmonellae could not be detected in any of the samples examined. Out of 19 enterobacteria suspected to be salmonellae 11 proved to be Proteus and 8 Citrobacter.     

Bacillus cereus food poisoning and its toxins

The genus Bacillus includes members that demonstrate a wide range of diversity from physiology and ecological niche to DNA sequence and gene regulation. The species of most interest tend to be known for their pathogenicity and are closely linked genetically. Bacillus anthracis causes anthrax, and Bacillus thuringiensis is widely used for its insecticidal properties but has also been associated with foodborne disease. Bacillus cereus causes two types of food poisoning, the emetic and diarrheal syndromes, and a variety of local and systemic infections. Although in this review we provide information on the genus and a variety of species, the primary focus is on the B. cereus strains and toxins that are involved in foodborne illness. B. cereus produces a large number of potential virulence factors, but for the majority of these factors their roles in specific infections have not been established. To date, only cereulide and the tripartite hemolysin BL have been identified specifically as emetic and diarrheal toxins, respectively. Nonhemolytic enterotoxin, a homolog of hemolysin BL, also has been associated with the diarrheal syndrome. Recent findings regarding these and other putative enterotoxins are discussed.     

食品过敏原的分类及安全管理

本文综述了食品过敏原的分类及管理研究现状。介绍了食物过敏和食品过敏原的定义、食品过敏原的分类、国内外食品过敏原的安全管理措施等三个方面的研究进展, 并对加强食品过敏原管理提出建议。     

外送餐引起产气荚膜梭菌食物中毒流行病学调查分析

目的查明发生在某工厂的食源性疾病暴发的可疑食品、致病因子及危险因素等,并对事件调查过程中暴露出的问题进行探讨,为今后类似事件的防控和调查提供参考依据。方法病例定义为于2019年3月3日～3月4日期间在M工厂加班职工中发生腹痛、腹泻(≥3次/24 h)或呕吐症状之一者,运用描述性和分析性流行病学方法开展病例访谈和回顾性研究。收集病例的粪便标本、剩余食品和相关环境样品进行病原分离和采用聚合酶链式反应(PCR)检测阳性菌株的毒素基因。结果检索到病例106名,罹患率为73.6%(106/144),临床症状以腹泻(78.3%,83/106)、腹痛(78.3%,83/106)为主,部分半腹部胀气、胀痛(9.4%,10/106),无发热;流行曲线为点源暴露模式,潜伏期为2～22 h,可疑餐次为2019年3月3日的午餐;单因素分析和Logistic回归分析结果显示,发病与红烧鱼块[相对危险度(RR)=1.55, 95%置信区间(95%CI):1.29～1.85]、蒜苗肉丝(RR=1.26, 95%CI:1.01～1.57)和雪菜烧鸭血(RR=1.47, 95%CI:1.16～1.87)有关;在3份肛拭子、3份环境样品中检出产气荚膜梭菌,菌株和2份剩余食品均检测出α毒素和产气荚膜梭菌肠毒素(CPE)基因。送餐的D企业在加工经营中存在着被细菌污染并繁殖的条件。结论本次事件是因食用某供餐企业提供的配送餐引起的产气荚膜梭菌食物中毒,外送餐做好后应迅速冷却、低温储存,不能立即进食的,在食前要充分加热。     

Pathogenesis of food poisoning due to enterococci

The enteropathogenic properties of enterococci having proteolytic characteristics were studied in experiments on isolated loops of the rat and rabbit small intestine. It was shown that Str. faecalis v. liguefaciens (4 strains) and Str. faecalis zymogenes (1 strain) possess enteropathogenic properties. However, the degree of pathogenicity varied, which was confirmed by characteristic macro- and microscopic changes seen in the ligated loops of the small intestine of the experimental animals.     

《食物中毒事故处理办法》出台

随着人们生活水平的提高,食品的安全性日益引起人们的重视。要求加强食品安全性,控制食物中毒事故发生的呼声日高。鉴于１９８１年发布的《食物中毒调查报告办法》已与现实形势不适应,卫生部制定了新的《食物中毒事故处理办法》。该办法于２０００年１月１日起施行,１９８１年１２月１日发布的《食物中毒调查报告办法》同时废止。第一章总则第一条为了及时处理和控制食物中毒事故,保障人民身体健康,根据《中华人民共和国食品卫生法》（以下称《食品卫生法》的规定,制定本办法。第二条本办法所指的食物中毒,是指食用了被生物性、化学…     

对4起群体性食物中毒事件的评析

为了解农村群体性食物中毒,对2003年第2季度在临夏州康乐、广河、和政3县农村连续发生的4起群体性食物中毒进行了分析,4起食物中毒共计446人用餐,发生中毒273人,总中毒患病率为61.21%,经实验室检测,在所采集样品中均检出变形杆菌(未进行生化分型).中毒主要发生在30岁以下人群,都是由共同进食同类食物引起,发生时间均在春夏季(4月、5月).通过分析这4次中毒事件,须吸取的教训是:应将农村群体性用餐纳入食品卫生监督管理;群体性活动中的饮食卫生差,应高度重视;少数民族地区宗教活动群体用餐多,而卫生意识差,须加强卫生宣教工作;农村畜禽检疫与卫生管理跟不上市场经济的发展;提高农民生活水平,使其讲求饮食质量,避免发生食物中毒;结合少数民族地区宗教活动等群体性聚餐较多的实际,制定相应的预防控制食物中毒对策.     

一起肉毒梭菌污染家庭腌制酸肉引起的食物中毒调查处置

目的查找病因,指导临床救治,以便为肉毒梭菌食物中毒事件制定防治措施提供依据。方法应用WS/T 83—1996《肉毒梭菌食物中毒诊断标准及处理原则》,通过现场流行病学调查、实验室检测和启动国家卫计委特效药系统紧急采购肉毒梭菌诊治血清应用于病人,分析致病原因与病程变化关系,确定诊治措施。结果确诊发病病人2例,仅1人住院。在住院患者血清中检出A、B型肉毒梭菌毒素,应用A、B型肉毒梭菌抗毒血清并对症治疗、机械通气,治疗25 d后,症状缓解,逐渐好转并康复出院。结论本次事件是由于进食被A、B型肉毒梭菌毒素污染的自家腌制酸肉导致的食物中毒事件。建议做好饮食安全宣传,加强食物中毒防控。     

食品防腐剂的分类、安全性及应用研究

植物精油是一类天然的抑菌剂,能够有效抑制多种肉源腐败菌和致病菌,在肉类工业中应用前景广泛。纳米乳液作为一种纳米级包埋系统,在改善精油的水溶性、稳定性和抑菌活性方面有明显效果,目前已成为肉类防腐保鲜领域的研究热点。因此,本文介绍了植物精油纳米乳液的构建方法（乳化方式、乳化剂）、基本特性（稳定性和生物利用率）,重点探讨了植物精油纳米乳液对肉源腐败菌和致病菌的抑菌活性、影响因素（精油种类、乳化方式、乳化剂、乳液粒径和微生物种类）,及其通过靶向结合、持续释放、被动运输等提高纯精油抑菌活性的内在机制,以期为植物精油纳米乳液在肉制品防腐保鲜中的研究及开发利用提供理论参考。