Studies on the genomic association between schistosomiasis and hepatitis C virus infection

Background: Schistosomiasis is an infection caused by blood flukes of the genus Schistosoma. Schistosomes are successful parasites, apparently as a result of prolonged co-evolution with their hosts. Studies done nationwide in Egypt found the highest risk of hepatitis C virus (HCV) co-infection is in those infested with schistosome without history of blood transfusions. However, the association between schistosomiasis and HCV infection is incompletely understood. Aims: The overall aim of this study was to assess whether or not a genomic association between schistosomal infestation and HCV infection exists. Materials and Methods: Oligonucleotide specific primers of HCV-polymerase chain reaction (PCR) diagnostics were used to screen the genomic DNA and cDNA library pool of Schistosoma mansoni as templates based on the end-point PCR approach. Results: Screening of schistosome DNA by PCR, lead to the detection of sequences similar to HCV. PCR products were obtained when adult worms genomic DNA were used as templates while no PCR products were amplified from S. mansoni λZAPII cDNA library pool. The resulting PCR products were sequenced and compared with the other closely related HCV sequence database at the website < http://hcv.lanl.gov>. Conclusions: This work demonstrates the existence of HCV and its replication in the genomic DNA of S. mansoni. In addition, it highlights the fact that the parasite can carry the virus genome and therefore, is considered as a nonhuman vector for the transmission of HCV infections.