Identification of the diagnostic and epidemiological potential of camel strain G6 in human cystic echinococcosis

Recent molecular studies detected the presence of camel G6 genotype in human samples in different countries including Egypt. However, none of them studied the diagnostic and epidemiological role of camel G6 genotype in patients' sera with cystic echinococcosis [CE]. Detection of camel G6 strain in patients' sera by polymerase chain reaction [PCR] and determination of changes in the genotype profile that might be influenced by the predominant transmission cycle during a certain time. Eighty subjects were divided into 2 main groups with 3 subgroups in each: Group I [31 CE cases with positive G6 PCR in parasite material obtained from their cysts] subdivided into Group IA [21 hepatic CE], Group IB [5 pulmonary CE], Group IC [5 multiple organ CE], Group II [49 control subjects] including Group IIA [29 patients with other parasitic diseases], Group IIB [10 patients with space occupying lesions] and Group IIC [10 healthy individuals]. DNA was extracted from CE patients' sera for amplification and sequencing. Hot-start specific G6 PCR for patients' sera [PCRs] revealed that all CE cases [100%] were of G6 genotype, with 100% sensitivity and 100% specificity and a specific band at 254 bp. Indirect hemagglutination test [IHAT] showed 61.29% sensitivity and 95.92% specificity. DNA sequencing of the amplified DNA fragments of patient's sera showed 100% homology with extracts from parasite materials taken from their own cysts [Gen Bank under the accession no. from GQ476732 to GQ476735], as well as with that of an Argentinean reference strain [provided from WHO reference laboratory]