Giardiasis Pattern among Different Age Categories: Childhood Assemblage B Proclaim Endemicity

Background: Giardiasis is one of the commonest intestinal parasitic diseases that affects wide range of age groups. We aimed to detect the pattern of Giardia intesti-nalis assemblages among symptomatic patients at the age of 2 up to 40 years. Methods: Stool samples were collected from 278 patients and examined micro-scopically and genetically for giardiasis. Giardia was diagnosed using wet mount examination and subjected to molecular assays targeting three genes, glutamate de-hydrogenase (gdh) using semi-nested PCR (nPCR), β-giardin (bg) and triose phos-phate isomerase (tpi) using nPCR. Amplified products were subjected to genotyping using PCR-restriction fragment length polymorphism (PCR-RFLP) targeting gdh and bg genes. Results: Among 48 samples positive by microscopy and by a minimum of one of the three used genes, genotyping was successful among 23 samples (47.9%). As-semblage B was more prevalent (16/23, 69.6%), than assemblage A (4/23, 17.4%) and 3 (13%) isolates were identified as assemblage B at gdh locus which later were identified as assemblage A at bg locus. Sub-assemblage AII (3/4, 75%) and sub-assemblage BIII (12/15, 66.7%) were predominate at gdh locus. Age groups was an estimated risk factor for infection with assemblage B with a peak (87.5%) during 6 to 12 years (P<0.05), diarrhea and abdominal pain (OR (95%CI) = .654 (.094, .963); .201 (.048, 1.009), respectively) were significantly associated with as-semblage B. Conclusion: It is recommended to suspect infection with giardiasis assemblage B by physicians during late childhood presenting with diarrhea and abdominal pain.