Detection and genotyping of torque teno virus (TTV) in healthy blood donors and patients infected with HBV or HCV in Qatar

Abstract

Torque Teno virus (TTV) has been associated with non A-G hepatitis. The goal of this study was to estimate the infection rates and genotypic characteristics of TTV in the State of Qatar. A total of 644 blood samples representing different nationalities: (i) Qatari (118) and (ii) non-Qatari (526) nationals (mostly from Arab and South Eeast Asia countries) were tested for the presence of TTV DNA by nested PCR. The majority (573) of the blood samples belonged to healthy blood donors, whereas 54 and 53 of the blood samples belonged to patients infected with hepatitis B virus (HBV) and hepatitis C virus (HCV), respectively. The results obtained showed that the TTV infection rates in the healthy blood donors, and those infected with HBV or HCV patients were 81.4, 90.75 and 84.9%, respectively. Significant association between TTV viremia and age, or nationality was observed. Sequence analysis of PCR fragments amplified from the 5'-untranslated region (5'-UTR) of all (531) TTV positive samples showed that 65.5% (348/531) of the PCR fragment sequences were classified into main genogroup 3, followed by main genogroups 5 (24%), 2 (5.8%), and 1 (4.7%). Genogroup 4 was not detected among the our studied subjects. Phylogenetic and pairwise analyses using sequences from TTV viremic samples also showed an overall close similarity to the main genogroup 3. In conclusion, there was no significant difference in the rates of TTV detection among Qataris and non-Qataris and several genotypes, mainly genotype 3, were isolated.

Prevalence of anelloviruses (TTV, TTMDV, and TTMV) in healthy blood donors and in patients infected with HBV or HCV in Qatar

“…This probably justifies the number of studies, specially on TTV, that evaluated the prevalence of the virus in HBV and HCV blood samples compared to the limited number of studies in healthy individuals especially in the Middle East region. In a previous study [8] we reported our finding concerning the prevalence of TTV in healthy blood donors and HBV/HBC patients in Qatar. Therefore, the objective of this study was to evaluate the TTMV and TTMDV prevalence rates in healthy, as well as, HBV and HCV subjects in Qatar and compare the findings to those in the previous TTV study.…”

“…The samples that were used in this project to detect TTMDV and TTMV DNA were exactly the same ones we used in our previous TTV published project [8], and the data from it were used again in this study for comparison purposes between the three anelloviruses.…”

“…Furthermore, infection with anelloviruses can be highly common reaching a 90% prevalence rate [8]. Reports on the prevalence of TTMV in humans indicated high rates of infection in French [9], Brazilian [10, 11] and in Norwegian [12] blood donors and also in French hemodialysis patients (95%) [13].…”

Phylogenetic Analysis of Torque Teno Virus in Thalassemic Children in Egypt

“…One study carried out in the Emirates showed a high prevalence of TTV among nonEmirati nationals (89%) compared to nationals (34.9%), but the study involved a mixed population of healthy and HCV and HBV patients and used the more conserved untranslated region of the virus DNA [24] . Another study in Qatar showed a similarly high prevalence, between 81 and 90%, but again it was carried out in healthy as well as HCV-infected patients and it included people of different nationalities [13] .…”

The Role Ischemia in Pathogenesis of Hepatitis С With Glomerulonephritis and Cancerogenesis

“…Анемия на современном этапе не имеет исчерпывающего патофизиологического обоснования, как и раскрытия механизмов снижения гемоглобина в крови больных гепатитом С и ВИЧ-инфицированных, предполагается, что анемия имеет многофакторную природу [6,38], что объясняет случаи неудачных попыток эмпирического применения эритропоэтина в лечении больных гепатитом С и ВИЧ-инфицированных [2,18,40].…”