Our knowledge on the susceptibility of humans to different genotypes of the zoonotic tapeworm Echinococcus granulosus and the genetic make-up of the cysts in multi-organ involvements is limited. This study aimed to identify the genotype profile of E. granulosus in patients undergoing hydatid surgery in an endemic area for cystic echinococcosis (CE) in southeastern Iran. Individuals who underwent hydatid cyst surgery were included in this study. Protoscoleces/germinal layers from each individual isolate were washed and kept in -20°C until use. Genotyping was carried out using PCR-sequencing of two mitochondrial CO1 and ND1 genes. Molecular phylogeny and haplotype network analysis of the human isolates were carried out using sequence data obtained from this study and National Center for Biotechnology Information (NCBI) databases. Forty-two patients (23 women and 19 men) participated in the study; the mean age was 43 years. Eighteen (42.9%) and 24 (57.1%) patients were infected by E. granulosus sensu stricto (G1-G3) and Echinococcus intermedius (G6 genotype), respectively. Molecular study showed mixed infection of G1 (in the liver and right lung) and G6 (in left lung) in a patient. The study showed a significantly high proportion of CE patients infected with the G6 genotype particularly in the southern parts of the province. In the present study a human CE patient infected by two species/genotypes of E. granulosus sensu lato is documented.
Keywords: Echinococcus canadensis; Echinococcus intermedius; co-infection; cystic echinococcosis; multi-organ hydatid cyst.