Abstract :
Giardiasis and other intestinal parasite infections are still prevalent and a public health concern, especially in areas with inadequate sanitation and hygiene. Giardia duodenalis infections can cause mild to severe symptoms, such as chronic diarrhea, malabsorption, and growth impairment in children, so early detection is essential. The commonly used fecal microscopy test has a low sensitivity, particularly for infections with low parasite loads or in the absence of symptoms. The development of molecular diagnostic methods based on the polymerase chain reaction (PCR) provides a more accurate and sensitive alternative by using specific genetic markers. This review of the literature looks at the roles of the 18S rRNA and β-giardin genes as molecular markers for the early detection of Giardia duodenalis infection. The review’s conclusions indicate that the 18S rRNA gene’s high sensitivity and robust sequence stability make it suitable for initial screening and epidemiological surveillance. In contrast, the β-giardin gene is useful for genotype analysis and diagnostic confirmation because of its higher specificity. The combination of these two genes may be the most effective diagnostic strategy to improve the accuracy of early Giardiasis detection in both clinical and epidemiological settings.
Keywords :
18S rRNA, Early Detection, Giardia duodenalis, molecular marker., PCR, β-giardinReferences :
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