Loop-Mediated Isothermal Amplification (LAMP) Assay for Rapid Detection of Salmonella enterica in Low-Resource Settings
DOI:
https://doi.org/10.47430/ujmr.25103.011Keywords:
Typhoid fever, Salmonella enterica, loop-mediated isothermal amplification (LAMP), rapid detectionAbstract
Typhoid fever remains a significant global health burden, particularly in regions with inadequate sanitation and limited access to safe water supplies. Traditional diagnostic methods, such as blood culture and biochemical assays, although considered the best standards, are labor-intensive and time-consuming, thereby limiting their practical utility in resource-constrained settings. This study aimed to develop a loop-mediated isothermal amplification (LAMP) assay for the rapid detection of S. enterica using conserved genomic regions (367 as targets. Unlike conventional PCR, which requires expensive thermal cyclers, our LAMP protocol utilizes a water bath to maintain a constant reaction temperature of 63°C for 90 minutes, significantly reducing equipment costs. Amplified products were rapidly detected by the addition of SYBR Green dye, which produced a distinct green fluorescence under blue light, enabling easy visual interpretation. Comparative analysis revealed that the LAMP assay demonstrated higher sensitivity—detecting Salmonella in 90% of isolates—compared to 85% for PCR, with both methods showing high specificity and no cross-reactivity with non-Salmonella species. These findings suggest that the LAMP assay provides a rapid, cost-effective, and sensitive alternative for typhoid diagnosis, offering promise for enhanced disease surveillance and management in low-resource settings.
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