Investigation of HGV and TTV infection in sera and saliva from non-hepatitis patients with oral diseases

AIM:To determine the frequencies of HGV and TTV infectionsin serum and saliva samples of non-hepatitis patients withoral diseases in Hangzhou area,and to understand thecorrelation between detected results of HGV RNA and/or TTVDNA in sera and in saliva from the same patients.METHODS:RT-nested PCR for HGV RNA detection andsemi-nested PCR for TTV DNA detection were performed inthe serum and saliva samples from 226 non-hepatitis patientswith oral diseases,and nucleotide sequence analysis.RESULTS:Twenty-seven(11.9 %)and 21(9.3 %)of the226 serum samples were only positive for HGV RNA andTTV DNA,respectively.10(4.4 %)and 9(3.9 %)of the226 saliva samples were only positive for HGV RNA andTTV DNA,respectively.And 7(3.1%)of the serum samplesand 2(0.9 %)of the saliva samples showed the positiveamplification results for both HGV RNA and TTV DNA.12saliva samples from the 34 patients(35.3 %)with HGV orHGV/TTV viremia and 11 saliva samples from the 28 patients(39.3 %)with TTV or HGV/TTV viremia were HGV RNAdetectable,respectively,including two patients positive forboth HGV RNA and TTV DNA in serum and saliva samples.No saliva samples from the 226 patients were found to beHGV RNA or TTV DNA detectable while their serum sampleswere negative for HGV or TTV.Homologies of the nucleotidesequences of HGV and TTV amplification products from theserum and saliva samples of the two patients comparedwith the reported sequences were 88.65-91.49 % and65.32-66.67 %,respectively.In comparison with thenucleotide sequences of amplification products betweenserum and from saliva sample from any one of the twopatients,the homologies were 98.58 % and 99.29 % forHGV,and were 98.65 % and 98.20 % for TTV,respectively.CONCLUSION: Relatively high carrying rates of HGV and/ or TTV in the sera of non-hepatitis patients with oral diseases in Hangzhou area are demonstrated. Parts of the carriers are HGV and/or TW positive in their saliva. The results of this study indicate that dentists may be one of the populations with high risk for HGV and/or TTV infection, and by way of saliva HGV and TTV may be transmitted among individuals.