Giardia intestinalis assemblages among Egyptian symptomatic/asymptomatic cases in Cairo

Giardia intestinalis is frequent enteric protozoa, affecting humans worldwide. Human infections aremainly caused by two genetically different assemblages call A & B. This cross-sectional study characterizedthe Giardia genotypes isolated from the stool of symptomatic and asymptomatic Egyptians inCairo and correlated these genotypes with the demographic and clinical data of the cases. Stool sampleswere collected from 389 individuals (245 complaining of gastrointestinal (GIT) symptoms and144 apparently healthy asymptomatic individuals), and microscopically examined. Positive Samplesfor G. intestinalis were molecularly characterized by Copro-nPCR targeting beta-giardin gene, andthen analyzed by RFLP for assemblage identification. Giardia was detected in 62 samples (15.9%); 53samples in symptomatic cases (21.6%) and 9 samples in asymptomatic individuals (6.25%). DNA ofpositive samples was amplified by nPCR-RFLP assays. There was a significant predominance of assemblageB among symptomatic (82.7%) and asymptomatic (77.8%) groups, while the rest of sampleshad assemblage A. Among the clinical data, only flatulence was significantly associated with Giardiainfection with assemblage B. Assemblage B is the predominant genotype found in Egypt in symptomaticand asymptomatic patients suggesting an anthropologic transmission cycle.Key Words: Giardia; genotyping; Assemblage; nPCR-RFLP; beta-giardin.