Phylogenetic Characteristics of Echinococcus granulosus Sensu Lato in Uzbekistan

Echinococcosis occurs mainly in areas with heavy livestock farming, such as Central Asia, America, and Australia. Echinococcus granulosus sensu lato (s.l.) infection causes echinococcosis in intermediate hosts, such as sheep, cattle, goats, camels, and horses. Numerous cases of echinococcosis occur in Uzbekistan as stock farming is a primary industry. Epidemiological and genetic studies of E. granulosus s.l. are very important for mitigating its impact on public health and the economy; however, there are no such studies on E. granulosus s.l. in Uzbekistan. In the present study, to determine which genotypes exist and are transmitted, we isolated Echinococcus sp. from definitive hosts (one isolate each from jackal and dog) and intermediate hosts (52 isolates from humans and 6 isolates from sheep) in Uzbekistan and analyzed the isolates by sequencing 2 mitochondrial DNA components (cox1 and nad1). The results showed that all of isolates except one belonged to the E. granulosus sensu stricto (s.s.) G1 and G3 genotypes. Phylogenetic analysis based on cox1 sequences showed that 42 isolates from humans, 6 isolates from sheep, and one isolate from jackal were the G1 genotype, whereas the remaining 8 isolates from human and the one isolate from dog were the G3 genotype. These results suggest that the G1 and G3 genotypes of E. granulosus s.s. are predominant in Uzbekistan, and both wild animals and domestic animals are important for maintaining their life cycle. Only one isolate from human sample was confirmed to be E. eqiinus (G4 genotype), which is known to be for the first time.

Prevalence of Intestinal Helminth Infections in Dogs and Two Species of Wild Animals from Samarkand Region of Uzbekistan

This study aimed to determine the prevalence of intestinal helminth parasitic infections and associated risk factors for the human infection among the people of Samarkand, Uzbekistan. Infection status of helminths including Echinococcus granulosus was surveyed in domestic and wild animals from 4 sites in the Samarkand region, Uzbekistan during 2015–2018. Fecal samples of each animal were examined with the formalin-ether sedimentation technique and the recovery of intestinal helminths was performed with naked eyes and a stereomicroscope in total 1,761 animals (1,755 dogs, 1 golden jackal, and 5 Corsac foxes). Total 658 adult worms of E. granulosus were detected in 28 (1.6%) dogs and 1 (100%) golden jackal. More than 6 species of helminths, i.e., Taenia hydatigena, Dipylidium caninum, Diplopylidium nolleri, Mesocestoides lineatus, Toxocara canis, and Trichuris vulpis, were found from 18 (1.0%) dogs. Six (T. hydatigena, Toxascaris leonina, Alaria alata, Uncinaria stenocephala, D. caninum, and M. lineatus) and 2 (D. nolleri and M. lineatus) species of helminths were also detected from 5 Corsac foxes and 1 golden jackal, respectively. Taeniid eggs were found in 2 (20%) out of 10 soil samples. In the present study, it was confirmed that the prevalences of helminths including E. granulosus are not so high in domestic and wild animals. Nevertheless, the awareness on the zoonotic helminth infections should be continuously maintained in Uzbekistan for the prevention of human infection.

Practical Algorisms for PCR-RFLP-Based Genotyping of Echinococcus granulosus Sensu Lato

Echinococcus granulosus sensu lato (s.l.) is a causative agent of cystic echinococcosis or cystic hydatid disease in humans and domestic and wild animals. The disease is a serious health problem in countries associated with poverty and poor hygiene practices, particularly in livestock raising. We introduced a practical algorism for genotyping the parasite, which may be useful to many developing countries. To evaluate the efficiency of the algorism, we genotyped 3 unknown strains isolated from human patients. We found that unknowns 1 and 3 were included in G1, G2, and G3 genotypes group and unknown 2 was included in G4 genotype (Echinococcus equinus) according to the algorisms. We confirmed these results by sequencing the 3 unknown isolates cox1 and nad1 PCR products. In conclusion, these new algorisms are very fast genotype identification tools that are suitable for evaluating E. granulosus s.l. isolated from livestock or livestock holders, particularly in developing countries.