Identification of Salmonella typhi in Blood Samples from Various Ethnic Adult Populations in Quetta through Selective Culture and Molecular Approaches
Research Article
DOI:
https://doi.org/10.31580/pjmls.v9i2.3112Keywords:
Blood tests, ELISA, Ethnic groups, PCR, Salmonella typhiAbstract
Objective: Salmonella typhi, the etiological agent of typhoid fever, remains a significant public health concern in developing countries. This study aimed to identify and confirm S. typhi in blood samples obtained from various ethnic adult populations in Quetta, Pakistan, using selective culture techniques and molecular approaches.
Methodology: A total of 234 blood samples were collected from adult patients belonging to different ethnic communities over a period of ten months. Samples were processed using selective media (XLD agar and MacConkey agar), biochemical tests, Gram staining, and polymerase chain reaction (PCR) for confirmation of S. typhi. Antimicrobial susceptibility testing was performed using the standard disc diffusion method.
Results: Among the 234 samples, 26% (n=61) tested positive for typhoid fever, while 74% (n=173) tested negative. Gender-based analysis revealed higher prevalence in males (18.0%) compared to females (8.0%). Age-wise distribution showed prevalence rates of 10.25% in the 18-20 years age group, 10.40% in the 18-20 years group, and 4.25% in the 18-25 years group. Ethnic distribution demonstrated the highest prevalence among Pashtoon (9.40%), followed by Baloch (7.30%), Punjabi (5.10%), and Hazara (4.20%) populations. PCR amplification confirmed S. typhi with specific bands at 230 bp. Antimicrobial susceptibility testing revealed resistance to multiple antibiotics including chloramphenicol, amoxicillin, penicillin G, polymyxin B, ciprofloxacin, metronidazole, lincomycin, and trimethoprim, while susceptibility was observed only to vancomycin.
Conclusion: The findings highlight the significant burden of typhoid fever in Quetta, particularly among specific ethnic groups and male populations. The study emphasizes the urgent need for improved water supplies, enhanced vaccination coverage, better sanitation infrastructure, and community awareness programs to control typhoid transmission in high-risk areas
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