Zaidi Mussaret B, McDermott Patrick F, Fedorka-Cray Paula, Leon Verónica, Canche Claudia, Hubert Susannah K, Abbott Jason, León Magda, Zhao Shaohua, Headrick Marcia, Tollefson Linda
Laboratorio de Investigación, Hospital General O'Horan, Mérida, Yucatan, Mexico.
Clin Infect Dis. 2006 Jan 1;42(1):21-8. doi: 10.1086/498508. Epub 2005 Nov 29.
We report the results of a 3-year Salmonella surveillance study of persons with diarrhea; asymptomatic children; and retail pork, poultry, and beef in Yucatan, Mexico.
Isolates were characterized according to serotype, antimicrobial susceptibility, and genetic relatedness with pulsed-field gel electrophoresis.
Salmonella Typhimurium was the most common serotype found in ill humans (21.8% of isolates), followed by Salmonella Agona (21% of isolates). Salmonella Enteritidis was a minor serotype (4.2% of isolates). Asymptomatic children carried S. Agona (12.1% of isolates), Salmonella Meleagridis (11.6% of isolates), Salmonella Anatum (8% of isolates) and S. Enteritidis (5.8% of isolates). A high percentage of retail meat samples contained Salmonella; it was most commonly found in pork (58.1% of samples), followed by beef (54% of samples) and poultry (39.7% of samples). Resistance to oral drugs used for the treatment of salmonellosis was observed for ampicillin (14.6% of isolates were resistant), chloramphenicol (14.0% of isolates), and trimethoprim-sulfamethoxazole (19.7% of isolates). Resistance to ceftriaxone emerged in 2002 and was limited to the serotype S. Typhimurium. Twenty-seven percent of the isolates were resistant to nalidixic acid, and none were resistant to ciprofloxacin. Multidrug resistance was most common among isolates of serotypes S. Typhimurium and S. Anatum. Pulsed-field gel electrophoresis showed that strains found in retail meats were genetically identical to strains found in both asymptomatic children and ill patients.
Our study found a high prevalence of Salmonella in retail meats and persons with enteric infection; many of these isolates were resistant to clinically important antimicrobials. A random selection of isolates from people and retail meat showed genetic relatedness, which suggests that, in Yucatan, considerable transfer of Salmonella occurs through the food chain.
我们报告了一项针对墨西哥尤卡坦州腹泻患者、无症状儿童以及零售猪肉、家禽和牛肉进行的为期3年的沙门氏菌监测研究结果。
根据血清型、抗菌药物敏感性以及脉冲场凝胶电泳分析的遗传相关性对分离株进行鉴定。
鼠伤寒沙门氏菌是患病人类中最常见的血清型（占分离株的21.8%），其次是阿哥纳沙门氏菌（占分离株的21%）。肠炎沙门氏菌是次要血清型（占分离株的4.2%）。无症状儿童携带阿哥纳沙门氏菌（占分离株的12.1%）、火鸡沙门氏菌（占分离株的11.6%）、鸭沙门氏菌（占分离株的8%）和肠炎沙门氏菌（占分离株的5.8%）。零售肉类样本中沙门氏菌的检出率很高；最常见于猪肉（占样本的58.1%），其次是牛肉（占样本的54%）和家禽（占样本的39.7%）。观察到氨苄西林（14.6%的分离株耐药）、氯霉素（14.0%的分离株）和甲氧苄啶-磺胺甲恶唑（19.7%的分离株）对用于治疗沙门氏菌病的口服药物有耐药性。对头孢曲松的耐药性于2002年出现，且仅限于鼠伤寒沙门氏菌血清型。27%的分离株对萘啶酸耐药，无一株对环丙沙星耐药。多重耐药在鼠伤寒沙门氏菌和鸭沙门氏菌血清型的分离株中最为常见。脉冲场凝胶电泳显示，零售肉类中发现的菌株在基因上与无症状儿童和患病患者中发现的数据相同。
我们的研究发现零售肉类和肠道感染患者中沙门氏菌的患病率很高；这些分离株中有许多对临床上重要的抗菌药物耐药。从人和零售肉类中随机选择的分离株显示出遗传相关性，这表明在尤卡坦州，沙门氏菌通过食物链发生了相当程度的传播。
