Abstract：
BACKGROUND: Typhoid fever is a fatal disease in humans that is caused by Salmonella typhi. S. typhi infections need immediate antibiotic therapy, and their extensive use has led to multidrug-resistant (MDR) pathogens. The use of bacteriophages is becoming a new way to treat these resistant bacteria. This research was directed to bacteriophage isolation against S. typhi and to determine phage-antibiotic synergism.
OBJECTIVE: To isolate bacteriophages targeting S. typhi, the causative agent of typhoid fever, and investigate their potential synergistic effects when combined with antibiotics.
METHODS: A cross-sectional study.
METHODS: The Widal test was positive; twenty diarrheal stool samples were taken, and for confirmation of S. typhi, different biochemical tests were performed. The disc-diffusion technique was used to determine antimicrobial resistance, and the double agar overlay method was used for bacteriophage isolation from sewage water against S. typhi. To test antibiotic-phage synergism, the S. typhi bacteria was treated by phages together with varying antibiotic concentrations.
RESULTS: Eleven samples were positive for S. typhi with black colonies on SS-agar. These were catalase and MR positive with alkali butt on TSI. Clear plaques were observed after the agar overlay. Isolated phages were stable at various pH and temperature levels. Synergism was observed on agar plate. The zone was enlarged when phages were combined with bacterial lawn culture and ciprofloxacin disk. Bacterial growth inhibition had a significant p-value of 0.03 in titration plates, with the phage-ciprofloxacin combination being more effective than the phage and antibiotic alone.
CONCLUSIONS: The study highlights the synergistic effects of isolated bacteriophages with antibiotics, which are not only effective against S. typhi infection but also decrease antibiotic resistance.
OBJECTIVE: To isolate bacteriophages targeting S. typhi, the causative agent of typhoid fever, and investigate their potential synergistic effects when combined with antibiotics.
METHODS: A cross-sectional study.
METHODS: The Widal test was positive; twenty diarrheal stool samples were taken, and for confirmation of S. typhi, different biochemical tests were performed. The disc-diffusion technique was used to determine antimicrobial resistance, and the double agar overlay method was used for bacteriophage isolation from sewage water against S. typhi. To test antibiotic-phage synergism, the S. typhi bacteria was treated by phages together with varying antibiotic concentrations.
RESULTS: Eleven samples were positive for S. typhi with black colonies on SS-agar. These were catalase and MR positive with alkali butt on TSI. Clear plaques were observed after the agar overlay. Isolated phages were stable at various pH and temperature levels. Synergism was observed on agar plate. The zone was enlarged when phages were combined with bacterial lawn culture and ciprofloxacin disk. Bacterial growth inhibition had a significant p-value of 0.03 in titration plates, with the phage-ciprofloxacin combination being more effective than the phage and antibiotic alone.
CONCLUSIONS: The study highlights the synergistic effects of isolated bacteriophages with antibiotics, which are not only effective against S. typhi infection but also decrease antibiotic resistance.
摘要：
背景：伤寒是由伤寒沙门氏菌引起的人类致命疾病。伤寒杆菌感染需要立即抗生素治疗，它们的广泛使用导致了多药耐药（MDR）病原体。噬菌体的使用正成为治疗这些耐药细菌的新方法。该研究涉及针对伤寒沙门氏菌的噬菌体分离和确定噬菌体-抗生素协同作用。
目的：分离针对伤寒沙门氏菌的噬菌体，伤寒的病原体，并研究它们与抗生素联合使用时的潜在协同作用。
方法：横断面研究。
方法：Widal试验为阳性；取20份腹泻粪便样本，为了确认伤寒沙门氏菌，进行了不同的生化试验.圆盘扩散技术用于确定抗菌素耐药性，双琼脂覆盖法用于从污水中分离针对伤寒沙门氏菌的噬菌体。为了测试抗生素-噬菌体的协同作用，通过噬菌体和不同的抗生素浓度处理伤寒沙门氏菌。
结果：11个样本在SS-琼脂上呈黑色菌落，伤寒沙门氏菌呈阳性。这些是过氧化氢酶和MR在TSI上呈碱性阳性。在琼脂覆盖后观察到清晰的斑块。分离的噬菌体在各种pH和温度水平下是稳定的。在琼脂平板上观察到协同作用。当噬菌体与细菌草坪培养物和环丙沙星圆盘结合使用时，该区域扩大了。在滴定板中，细菌生长抑制具有0.03的显着p值，噬菌体-环丙沙星组合比单独的噬菌体和抗生素更有效。
结论：该研究强调了分离的噬菌体与抗生素的协同作用，它们不仅对伤寒沙门氏菌感染有效，而且还降低了抗生素耐药性。
目的：分离针对伤寒沙门氏菌的噬菌体，伤寒的病原体，并研究它们与抗生素联合使用时的潜在协同作用。
方法：横断面研究。
方法：Widal试验为阳性；取20份腹泻粪便样本，为了确认伤寒沙门氏菌，进行了不同的生化试验.圆盘扩散技术用于确定抗菌素耐药性，双琼脂覆盖法用于从污水中分离针对伤寒沙门氏菌的噬菌体。为了测试抗生素-噬菌体的协同作用，通过噬菌体和不同的抗生素浓度处理伤寒沙门氏菌。
结果：11个样本在SS-琼脂上呈黑色菌落，伤寒沙门氏菌呈阳性。这些是过氧化氢酶和MR在TSI上呈碱性阳性。在琼脂覆盖后观察到清晰的斑块。分离的噬菌体在各种pH和温度水平下是稳定的。在琼脂平板上观察到协同作用。当噬菌体与细菌草坪培养物和环丙沙星圆盘结合使用时，该区域扩大了。在滴定板中，细菌生长抑制具有0.03的显着p值，噬菌体-环丙沙星组合比单独的噬菌体和抗生素更有效。
结论：该研究强调了分离的噬菌体与抗生素的协同作用，它们不仅对伤寒沙门氏菌感染有效，而且还降低了抗生素耐药性。
