臺灣博碩士論文加值系統

沙門氏菌 (Salmonella spp.)是造成腹瀉常見的病原菌之一，為提高臨床檢驗分離與鑑別的敏感度及特異性，本研究評估3種商品化的培養基：沙門氏菌呈色培養基CAS (CHROMagar Salmonella medium)、海克通氏腸內菌培養基HE (Hektoen enteric agar)及木糖離胺酸去氧膽酸鹽培養基XLD (Xylose lysine desoxycholate agar)與3種（商品化的）增菌液：革蘭氏陰性菌增菌液GN (Gram-negative broth)、亞硒酸鹽增菌液SB (Selenite broth)及亞硒酸亮綠磺胺鹽增菌液SBG (Selenite brilliant green sulfa enrichment broth)在提高臨床檢驗分離與鑑別之可行性。本研究共收集459個臨床腹瀉病人的糞便檢體，其中304個檢體用於比較直接接種及評估GN及SB對Salmonella spp.菌株的增菌效果；另外155個檢體則用於比較SB及SBG增菌效果。Salmonella spp.鑑定方式包括生化反應鑑定及血清分型。研究結果共分離出109株Salmonella spp.，可區分為22種血清型，檢體用生理食鹽水混合均勻後再接種比肛門拭子直接塗抹接種於培養基有較多的分離菌株 （前者42株，後者29株）。在未增菌的情況下，XLD的敏感度及特異性分別為53.5%及87.6%較CAS （敏感度：35.2%、特異性83.9 %）及HE （敏感度：40.9%、特異性81.5%）培養基為佳。經過GN增菌後再接種於HE及XLD培養基其敏感度分別為45.1%及52.1%顯著優於CAS培養基之28.1%，特異性則三者之間無顯著差異。以SB增菌後再接種，XLD為較佳之選擇，其敏感度為86.%，特異性為75.7%。就增菌液的增菌效果而言，SB增菌後的沙門氏菌分離檢體數為66件，明顯高於未經增菌45件及GN增菌45件 （p<0.005），SB與SBG的增菌後檢體陽性率無顯著差異，但SBG特異性為85.2%明顯優於SB的69.6%。偽陽性菌株的分析結果，HE培養基比CAS或XLD培養基有較多的Citrobacter spp.造成的偽陽性結果，而CAS培養基分離Pseudomonas aeruginosa的檢體數則明顯多於HE及XLD，以SB增菌後的Citrobacter spp.及Pseudomonas aeruginosa分離檢體數明顯多於GN增菌液，以SBG增菌液取代SB則可明顯抑制Citrobacter spp.及Pseudomonas aeruginosa，有效改善培養特異性。
由糞便檢體培養Salmonella spp.時使用SBG增菌液可有效改善培養之敏感度及特異性，解決各培養基之敏感度或特異性不佳的缺點，且此時不管搭配CAS, HE或XLD敏感度及特異性三者之間顯著差異，故培養分離Salmonella spp.應常規使用SBG增菌液，且搭配CAS培養基時因為其偽陽性菌落多為Pseudomonas aeruginosa可以簡單的氧化酶試驗與Salmonella spp.區分，加上氧化酶試驗後CAS培養基的特異性可由原來的88.0%提高為94.0%，特異性高可減少確認所需的時間、試劑及人力故分離人類糞便檢體中Salmonella spp.的最佳組合為SBG增菌液加上CAS培養基。

Salmonellae is one of the most common causes of human gastroenteritis. This study compared the performance of three selective media namely CAS (CHROMagar Salmonella medium), HE (Hektoen enteric agar) and XLD (Xylose lysine desoxycholate agar) and three enrichment broths namely GN (Gram-negative broth), SB (Selenite broth) and SBG (Selenite brilliant green sulfa enrichment broth) to optimize the use of plating media and enrichment broths for isolation of Salmonella spp. from human stools. The 304 stools were cultured onto the above three selective media by direct inoculation and after enrichment in GN and SB. The other 155 stools were tested for SBG and SB enrichment experiments. The standard biochemical identification tests and the serogrouping test were also used to identify Salmonella spp. The 109 Salmonella belong to 20 serotypes. The isolation rate of Salmonella is higher when stools were suspended in saline than plated on HE and XLD directly (42 isolates and 29 isolates, respectively). The sensitivity and specificity for direct plating were 53.5% and 87.6%, respectively, for XLD agar, and for CAS these values were 35.2% and 83.9%, respectively, and for HE these values were 40.9% and 81.5%, respectively. The sensitivities of XLD for direct plating was statistically significantly higher than CAS and HE The sensitivities for the detection of Salmonellae after GN enrichment were 45.1% and 52.1% for HE and XLD was statistically significantly higher than CAS 28.1%. The specificity for the detection of Salmonellae after GN enrichment on CAS, HE, XLD were not significantly different. XLD medium can be recommended for use for the isolation of Salmonella spp. with SB enrichment (sensitivity, 86.0%, specificity, 75.7%). The SB (66 isolates) enrichment procedure increased the number of Salmonella spp. isolates was significantly different from GN (45 isolates) and without enrichment (45 isolates) (p<0.005). Althought SB and SBG were not significantly different from each other in sensitivity, but the specificity of SBG (85.2%) was better than SB (69.6%) (p<0.005). There were more strains Citrobacter spp. on HE medium then CAS and XLD medium (p<0.005) and more strains Pseudomonas aeruginosa on CAS medium then HE (p<0.01) and XLD medium (p<0.005). There were more Citrobacter spp.and Pseudomonas aeruginosa after SB enrichment than SBG (p<0.05).
The use of plating on CAS, HE, XLD after SBG enrichment demonstrated high levels of sensitivity and specificity were not significantly different from each other. It can be recommended for the use for the isolation of Salmonella spp. from human stools. The specificity of the CAS was 88.0% after slective enrichment in SBG, while the specificity after oxidase test ruled out false positive result was 94.0%. The higher specificity reduces the need for confirmatory test, thereby cutting technical time and reagent requirements. The CAS with slective enrichment in SBG can be recommended as best choice for Salmonella isolation from human stools.

目錄

封面內頁
簽名頁
授權書　　　　　　　　　　　　　　　　　　　　　　 iii
中文摘要　　　　　　　　　　　　　　　　　　　　　 v
英文摘要　　　　　　　　　　　　　　　　　　　　　 vii
誌謝　　　　　　　　　　　　　　　　　　　　　　　 ix
目錄　　　　　　　　　　　　　　　　　　　　　　　 x
圖目錄　　　　　　　　　　　　　　　　　　　　　　 xiii
表目錄　　　　　　　　　　　　　　　　　　　　　　 xiv
試劑簡稱說明　　　　　　　　　　　　　　　　　　　 xvi
第一章 緒言　　　　　　　　　　　　　　　　　　　 1
第二章 文獻回顧
2.1 沙門氏菌簡介　　　　　　　　　　　　　　　 3
2.2 沙門氏菌命名方法　　　　　　　　　　　　　 4
2.3 菌種與疾病之關係　　　　　　　　　　　　　 7
2.4 沙門氏菌之抗藥性　　　　　　　　　　　　　 10
2.5 非培養方式的鑑定方法　　　　　　　　　　 11
2.6 沙門氏菌選擇性培養基及增菌液之比較
（1）傳統式分離沙門氏菌培養基介紹　　　 12
（2）呈色培養基介紹　　　　　　　　　　　　 13
（3）培養基敏感度及特異性比較　　　　　　 16
（4）沙門氏菌增菌液比較　　　　　　　　　 21
（5）培養基培養時間的影響　　　　　　　　 26
第三章 材料與方法
3.1 增菌液及選擇性培養基　　　　　　　　　　　 28
3.2 沙門氏菌菌株測試CAS, HE及XLD培養基
分離沙門氏菌的能力　　　　　　　　　　　　
28
3.3 臨床檢體測試　　　　　　　　　　　　　　　 29
3.4 統計分析　　　　　　　　　　　　　　　　　　 30
第四章 結果與討論
4.1 各培養基之沙門氏菌確認菌株測試　　　　　 33
4.2 臨床檢體測試結果　　　　　　　　　　　　　 33
（1）增菌液種類對分離沙門氏菌敏感度
及特異性的影響　　　　　　　　　　　　
36
（2）不同增菌液增菌情況下各培養基對
分離沙門氏菌敏感度及特異性的影響　
38
（3）偽陽性菌落分析　　　　　　　　　　　　 41
（4）培養基培養時間對結果之影響　　　　　 44
4.3 臨床檢體測試結果討論　　　　　　　　　　　
（1）SBG增菌液具高特異性原因分析　　　　 46
（2）SBG增菌效果與LOUIS試驗比較　　　 47
（3）CAS培養基與其他利用C8酯酶為分析
原理的培養基分離沙門氏菌特定血清形
能力的比較　　　　　　　　　　　　　　　

47
（4）調懸浮液後再接種可提高培養敏感度
之佐證　　　　　　　　　　　　　　　　　
48
（5）培養基最適培養時間　　　　　　　　　　 49
（6）本實驗所分離之所有沙門氏菌是否
會在CAS, HE及XLD形成偽陰性菌落　
49
（7）抑制或區分偽陽性菌落方法之探討　　　 50
（8）疑似沙門氏菌菌落判讀方式之影響　　　　　　　 50
第五章 結論　　　　　　　　　　　　　　　　　　　　　　　 52
引用文獻　　　　　　　　　　　　　　　　　　　　　　　　 53

圖目錄

圖3.1. 比較未經增菌、GN或SB增菌後各培養基
敏感度及特異性實驗流程　　
31
圖3.2. 比較SB及SBG增菌效果實驗流程　　 32


表目錄

表1. 沙門氏菌屬6個亞群的特性　　 4
表2. 沙門氏菌屬6個亞群（subgroups）不同
命名方式對照　　
6
表3. 世界衛生組織所公佈截至2002年沙門氏菌各
subspecies的血清分型數目　　
7
表4. Salmonella subspecie I 血清型在人類
及脊堆動物引起之疾病　　
9
表5. 台灣及美國最常感染人類的沙門氏菌
血清分型前十名　　
10
表6. 常用沙門氏菌培養基所含的選擇性成分　　 16
表7. HE培養基分離沙門氏菌能力之相關研究結果比較　 18
表8. XLD培養基分離沙門氏菌能力之相關研究結果比較 20
表9. CAS培養基分離沙門氏菌能力之相關研究結果比較 21
表10. 常用沙門氏菌增菌液所含的選擇性成分　　 22
表11. SB增菌液分離沙門氏菌能力
之相關研究結果比較　　
24
表12. 本實驗臨床檢體所分離之沙門氏菌各血清型株數 34
表13. 不同增菌液及選擇性培養基組合
分離沙門氏菌之敏感度及特異性　　

35
表14. 比較各增菌液間沙門氏菌分離件數
及偽陽性檢體件數是否有差異　　
37
表15. 不同增菌情況下各種培養基分離
沙門氏菌能力之比較　　
40
表16. 不同增菌情況下各種培養基間偽陽性菌落數之比較 41
表17. 各增菌液及培養基組合的偽陽性菌落明細表　　 43
表18. 24及48小時不同培養時間各增菌液與培養基
組合分離沙門氏菌之敏感度及特異性比較　　
45


試劑簡稱說明

CAS CHROMagar Salmonella medium
GN Gram-negative broth
HE Hektoen enteric agar
SB Selenite broth
SBG Selenite brilliant green sulfa enrichment broth
XLD Xylose lysine desoxycholate agar

1. 邱政洵。1996。北台灣地區沙門氏菌感染之現況並以分子生物學及生物學方法探討沙門氏菌之毒性質體與其致病性和宿主特異性之關係：2。私立長庚大學臨床醫學研究所博士論文。台灣。
2. 陳光爐、葉姿暖、李祥吉、蔡金來、邱秀櫻、王添貴、李智隆、蘇勳璧、吳和生及林鼎翔。2003。台灣地區1991-2001年沙門氏鼠傷寒桿菌抗藥性趨勢分析。疫情報導19（12）：619-633。
3. 陳宗佑。2003。台灣地區鼠傷寒沙門氏菌之分子流行病學研究1998~2002年：1。私立中國醫藥學院環境醫學研究所碩士論文。台灣。
4. Abdalla, S., Vila, J. and Jimenez de Anta, M. T. 1994. Identification of Salmonella spp. with Rambach agar in conjunction with the 4-methylumbelliferyl caprylate （MUCAP） fluorescence test. Br. J. Biomed. Sci. 51: 5-8.
5. Alvarez, J., Sota, M., Vivanco, A. B., Perales, H., Cisterna, R., Rementeria, A. and Garaizar, J. 2004. Development of a multiplex PCR technique for detection and epidemiological typing of Salmonella in human clinical samples. J. Clin. Microbiol. 42: 1734-1738.
6. Bäumler, A. J., Tsolis, R. M., Ficht, T. A. and Adams, L. G. 1998. Evolution of host adaptation in Salmonella enterica. Infect. Immun. 66: 4579-4587.
7. Benge, G. M. 1989. Detection of Salmonella species in faeces by latex agglutination in enrichment broth. Eur. J. Microbiol. Infect. Dis. 8: 294-298.
8. Blom, M., Meyer, A., Gerner-Smidt, P., Gaarslev, K. and Espersen, F. 1999. Evaluation of statens serum institut enteric medium for detection of enteric pathogens. J. Clin. Microbiol. 37: 2312-2316.
9. Brenner, F. W., Villar, R. G., Angulo, F. J., Tauxe, R. and Swaminathan, B. 2000. Salmonella nomenclature. J. Clin. Microbiol. 38: 2465-2467.
10. Buchwald, D. S. and Blaser, M. J. 1984. A review of human salmonellosis：Ⅱ duration of excretion following infection with nontyphi Salmonella. Rev. Infect. Dis. 6: 345-356.
11. Busse, M. 1995. Media for Salmonella. Int. J. Food Microbiol. 26: 117-131.
12. Cassar, R. and Cuschieri, P. 2003. Comparison of Salmonella chromogenic medium with DCLS agar for isolation of Salmonella species from stool specimens. J. Clin. Microbiol. 41: 3229–3232.
13. CDC, 2004. CDC. Salmonella surveillance： annual summary, 2003. p. iii and p. 22. Atlanta, Georgia: US department of health and human services,
14. Chang, C. T., Yuo, C. Y., Shen, H. C., Li, A. M., Chen, C. Y., Chou, J. L. and Huang, S. P. 1999. Recovery of Salmonella by using selenite brilliant green sulfa enrichment broth. J. Clin. Microbiol. 37: 4120–4123.
15. Chen, Y. H., Chen, T. P., Tsai, J. J., Hwang, K. P., Lu, P. L., Chen, H. H. and Peng, C. F. 1999. Epidemiological study of human salmonellosis during 1991-1996 in southern Taiwain. Kaohsiung J. Med. Sci. 15: 127-136.
16. Chiu, C. H. and Ou, J. T. 1996. Rapid identification of Salmonella serovars in feces by specific detection of virulence gene, invA and spvC, by an enrichment broth culture-multiplex PCR combination assay. J. Clin. Microbiol. 34: 2619-2622.
17. Chiu, C. H., Su, L. H., Hung, C. C., Chen, K. L. and Chishih, C. 2004. Prevalence and antimicrobial susceptibility of serogroup D nontyphoidal Salmonella in a university hospital in taiwain. J. Clin. Microbiol. 42: 415-417.
18. Chiu, C. H., Su, L. H. and Chishih, C. 2004. Salmonella enterica serotype choleraesuis：epidemiology, pathogenesis, clinical disease and treatment. Clin. Microbiol. Rev. 17: 311-322.
19. Cooke, V. M., Miles, R. J., Price, R. G. and Richardson, A. C. 1999. A novel chromogenic ester agar medium for detection of Salmonellae. Appl. Environ. Microbiol. 65: 807-812.
20. Dusch, H. and Altwegg, M. 1993. Comparison of Rambach agar, SM-ID medium and Hektoen enteric agar for primary isolation of nontyphi Salmonella from stool samples. J. Clin. Microbiol. 31: 410-412.
21. Dusch, H. and Altwegg, M. 1995. Evaluation of five new plating media for isolation of Salmonella species. J. Clin. Microbiol. 33: 802-804.
22. Eigner, U., Reissbrodt, R., Hammann, R. and Fahr, A. M. 2001. Evaluation of a new chromogenic medium for the isolation and presumptive identification of Salmonella species from stool specimens. Eur. J. Clin. Microbiol. Infect. Dis. 20: 558-565.
23. FarmerIII, J. J., Davis, B. R., Hickman-Brenner, F. W., McWhorter, A., Huntley-Carter, G. P., Asbury, M. A., Riddle, C., Wathen-Grady, H. G., Elias, C., Fanning, G. R., Steigerwalt, A. G., O`hara, C. M., Morris, G. K., Smith, P. B. and Brenner, D. J. 1985. Biochemical identification of new species and biogroups of Enterobacteriaceae isolated from clinical specimens. J. Clin. Microbiol. 21: 46-76.
24. Fierr, J. and Guiney, D. G. 2001. Diverse virulence traits underlying different clinical outcomes of Salmonella infection. J. Clin. Invest. 107: 775-780.
25. Forward, K. R. and Rainnie, B. J. 1997. Use of selenite enrichment broth for the detection of Salmonella from stool： a report of one year experience at a provincial public health laboratory. Diagn. Microbiol. Infect. Dis. 29: 215-217.
26. Gaillot, O., Camillo, P. D., Berche, P., Courcol, R. and Savage, C. 1999. Comparison of CHROMagar Salmonella medium and Hektoen enteric agar for isolation of Salmonellae from stool samples. J. Clin. Microbiol. 37: 762–765.
27. Goldberg, M. B. and Rubin, R. H. 1988. The spectrum of Salmonella infection. Infect. Dis. Clin. North. Am. 2: 571-598.
28. Gray, S. and Glancy, J. 2003. Failure to detect Salmonella enterica serovar Dublin on aes laboratoire salmonella agar plate. J. Clin. Microbiol. 41: 4003.
29. Huang, I. F., Wagener, M. M., Hsieh, K. S., Liu, Y. C., Wu, T. C., Lee, W. Y. and Chiou, C. C. 2004. Nontyphoid salmonellosis in Taiwan children: clinical manifestations, outcome and antibiotic resistance. J. Pediatr. Gastroenterol. Nutr. 38: 518-523.
30. Inoue, K., Miki, K., Tamura, K. and Sakazaki, R. 1996. Evaluation of L-pyrrolidonyl peptidase paper strip test for differentiation of members of the family Enterobacteriaceae, particularly Salmonella spp. J. Clin. Microbiol. 34: 1811-1812.
31. Kelly, S., Cormican, M., Parke, L. and Corbett-Feeney, G. 1999. Cost-effective methods for isolation of Salmonella enterica in the clinical laboratory. J. Clin. Microbiol. 37: 3369.
32. Kotetishvili, M., Stine, O. C., Kreger, A., Morris, J. J. G. and Sulakvelidze, A. 2002. Multilocus sequence typing for characterization of clinical and environmental Salmonella strains. J. Clin. Microbiol. 40: 1626-1635.
33. Konerman, E. M., Allen, S. D., Janda, W. M., Schreckenberger, P. C. and Winn Jr, W. C. 1997. Color atlas and textbook of diagnostic microbiology. (15nd ed.) p. 171-252. Lippinocott, Philadephia, New York, USA.
34. La`zaro, D. R., Herna`ndez, M., Esteve, T., Hoorfar, J. and Pla, M. 2003. A.rapid and direct real time PCR-based method for identification of Salmonella spp. J. Microbiol. Methods 54: 381-390.
35. Lee, C. Y., Chiu, C. H., Chuang, Y. Y., Su, L. H., Wu, T. L., Chang, L. Y., Huang, Y. C. and Lin, T. 2002. Multidrug-resistant non-typhoid Salmonella infections in a medical center. J. Microbiol. Immunol. Infect. 35: 78-84.
36. Maddocks, S., Olma, T. and Sharon, C. 2002. Comparison of CHROMagar Salmonella medium and xylose-lysine-desoxycholate and salmonella-shigella agars for isolation of Salmonella strains from stool samples. J. Clin. Microbiol. 40: 2999–3003.
37. Manafi, M., Kneifel, W. and Bascomb, S. 1991. Fluorogenic and chromgenic substrates used in bacterial diagnostics. Microbiol. Rev. 55: 335-348.
38. Manafi, M. 1996. Fluorogenic and chromgenic enzyme substrates in culture media and identification tests. Int. J. Food Microbiol. 31: 45-58.
39. Manafi, M. 2000. New developments in chromogenic and fluorogenic culture media. Int. J. Food Microbiol. 60: 205-218.
40. McDonough, P. L., Shin, S. J. and Lein, D. H. 2000. Diagnostic and public health dilemma of lactose-fermenting Salmonella enterica serotype typhimurium in cattle in the Northeastern United States. J. Clin. Microbiol. 38: 1221-1226.
41. Mcgowan, K. L. and Rubenstein, M. T. 1989. Use of a rapid latex agglutination test to detect Salmonella and Shigella antigens from gram-negative enrichment broth. Am. J. Clin. Pathol. 92: 679-682.
42. Metzler, J. and Nachamkin, I. 1988. Evaluation of a latex agglutination test for the detection of Salmonella and Shigella spp. by using broth enrichment. J. Clin. Microbiol. 26: 2501-2504.
43. Nye, K. J., Fallon, D., Frodsham, D., Gee, B., Graham, C., Howe, S., Messer, S. and Turner, T. 2002. An evaluation of performance of XLD, DCA, MLCB and ABC agar as direct plating media for the isolation of Salmonella enterica from faeces. J. Clin. Pathol. 55: 286-288.
44. Olsen, S. J., Ying, M., Davis, M. F., Deasy, M., Holland, B., Iampietro, L., Baysinger, C., Sassano, F., Polk, L. D., Gormley, B., Hung, M. J., Pilot, K., Orsini, M., Van Duyne, S., Rankin, S., Genese, C., Bresnitz, E. A., Smucker, J., Moll, M. and Sobel, J. 2004. Multidrug resistant Salmonella typhimurium infection from milk contaminated after pasteurization. Emerg. Infect. Dis. 10: 932-935.
45. Pan, T. M. and Liu, Y. J. 2002. Identification of Salmonella enteritidis isolates by polymerase chain reaction and multiplex polymerase chain reaction. J. Microbiol. Immunol. Infect. 35: 147-151.
46. Perez, J. M., Cavalli, P., Roure, C., Renac, R., Gille, Y. and Freydiere, A. M. 2003. Comparison of four chromogenic media and Hektoen agar for detection and presumptive identification of Salmonella strains in human stools. J. Clin. Microbiol. 41: 1130–1134.
47. Perry, J. D., Riley, G., Gould, F. K., Perez, J. M., Boissier, E., Ouedraogo, R. T. and Freydiere, A. M. 2002. Alafosfalin as a selective agent for isolation of Salmonella from clinical samples. J. Clin. Microbiol. 40: 3913-3916.
48. Persaud, C. A. and Eykyn, S. J. 1994. Stool culture: are you getting value for money?. J. Clin. Pathol. 47: 790-792.
49. Poisson, D. M., Niocel, B., Florence, S. and Imbault, D. 1992. Comparison of Hektoen and salmonella-shigella agar on 6033 stools of human origin submitted for routine isolation of Salmonella sp. and Shigella sp. Pathol. Biol. (Paris) 40: 21-24.
50. Popoff, M. Y., Bockemühl, J. and Gheesling, L. L. 2004. Supplement 2002 (no. 46) to the Kauffmann-White scheme. Res. Microbiol. 155: 568-570.
51. Qutaishat, S. S., Stemper, M. E., Spencer, S. K., Borchardt, M. A., Opitz, J. C., Monson, T., Anderson, J. L. and Ellingson, J. L. 2003. Transmission of Salmonella enterica serotype typhimurium DT104 to infants throught mother,s breast milk. Pediatrics. 111: 1442-1446.
52. Ramos, J. M., Cuenca-Estrella, M., Ales, J. M. and Soriano, F. 1996. Epidemiological profile of non-typhi salmonellosis in a hospital in urban Madrid (1980-1994). Enferm. Infecc. Microbiol. Clin. 14: 245-351.
53. Rohner, P., Dharan, S. and Auckenthaler, R. 1992. Evaluation of the wellcollex colour salmonella test for detection of Salmonella spp. in enrichment broths. J. Clin. Microbiol. 30: 3274-3276.
54. Ruiz, G. J., Lorente, S. I., Perez, S. J., Simarro, C. E. and Martinez, C. L. 1998. Evaluation of methods for Salmonella species using modified semisolid Rappaport-Vassiliadis medium and salmonella -shigella agar. Eur. J. Clin. Microbiol. Infect. Dis. 17: 791-793.
55. Ruiz, J., Núñez, M. L., Díaz, J., Lorente, I., Perez, J. and Gómez, J. 1996. Comparison of five plating media for isolation of Salmonella species from human stools. J. Clin. Microbiol. 34: 686-688.
56. Sirinavin, S., Pokawattana, L. and Bangtrakulnondh, A. 2004. Duration of nontyphoidal Salmonella carriage in asymptomatic adults. Clin. Infect. Dis. 38: 1644-1645.
57. Stone, G. G., Oberst, R. D., Hays, M. P., Mcvey, S., Galland, J. C., CurtissIII, R., Kelly, S. M. and Chengappa, M. M. 1995. Detection of Salmonella typhimurium from rectal swabs of experimentally infected beagles by short cultivation and PCR-hybridization. J. Clin. Microbiol. 33: 1292-1295.
58. Taylor, W. I. and Schelhart, D. 1975. Effect of temperature on transport and plating media for enteric pathogens. J. Clin. Microbiol. 2: 281-286.
59. Wilson, G. 2004. Rapid and economical method for biochemical screening of stool isolates for Salmonella and Shigella species. J. Clin. Microbiol. 42: 4821-4823.
60. Winfield, M. D. and Groisman, E. A. 2003. Role of nonhost environments in the lifestyles of Salmonella and Escherichia coli. Appl. Environ. Microbiol. 69: 3687-3694.
61. Wokatsch, R. and Rohde, R. 1976. Comparative study of different nutrient media used for the isolation of Salmonella in routine laboratories. Zentralbl. Bakteriol. 234: 287-293.
62. Yang, Y. J., Liu, C. C., Wang, S. M., Wu, J. J., Huang, A. H. and Cheng, C. P. 1998. High rates of antimicrobial resistance among clinical isolates of nontyphoidal Salmonella in taiwan. Eur. J. Clin. Microbiol. Infect. Dis. 17: 880-883.