Genetic variants of giardia lamblia isolates from food handlers in Erbil city

Background and objective: Giardia lamblia is a flagellated protozoan that lives and proliferates in the small intestine of human and other mammals causing gastrointestinal disorder called giardiasis. Giardiasis mainly spreads in developing countries which lack sanitation and hygiene awareness and persons become infected by ingestion of contaminated food and water with mature cysts. This study was designed to detect the distribution of giardiasis in human and to differentiate between the assemblages of Giardia lamblia A and B by using Glutamate dehydrogenase (gdh) gene Methods: A total of 2000 fecal samples were collected from symptomatic and asymptomatic food handler aged ranged between (20-30) and more than 30 years old that regularly attend the central laboratory in Erbil city. Primary diagnosis depends on a direct microscopic examination of the stool. Genotyping was done for Giardia positive samples (n = 39) targeting the Glutamate dehydrogenase gene (gdh) using two sets of primers for amplification of 458bp fragment, by RFLP and PCR-sequencing screening methods for G. lamblia. Results: Out of the total 2000 samples screened for G. lamblia, 39 (1.95 %) were positive. According to the multiple alignment results, it was found that the isolates belonged to sub-assemblage AII 21 (53.8%), assemblage B 11 (28.2%), sub-assemblage BIII 9 (81.8%) and sub-assemblage BIV2(18.2%) genotypes. No statistically significant result was found between symptomatic and asymptomatic as assemblage and sub-assemblage genotypes. Conclusion: The present study provides the first data on the assemblages and sub-assemblages of G. lamblia in food-handlers in Kurdistan region, Iraq. Identification and confirming of AII, B, BIII, and BIV genotypes in Erbil community indicates the anthroponotic and anthropozoonotic transmission cycle of Giardia infection. Our understanding of the diversity of G.lamblia mainly comes from the sequence information of multiple gene loci.