Prevalence of TTV DNA among children with a history of transfusion or liver disease

Abstract

The prevalence rates of serum TT virus (TTV) DNA among children with or without a history of transfusion or liver disease were studied by polymerase chain reaction (PCR) using either the Okamoto primer set or the Takahashi primer set developed more recently. Using Okamoto and Takahashi primer sets, the prevalence rates were 31.6% (12/38) and 78.9% (30/38), respectively, for children with a history of blood transfusion (including malignant and non-malignant groups) and 6.7% (2/30) and 60% (18/30), respectively, for children without a history of blood transfusion. Among pregnant women, these rates were 12.9% (4/31) and 61.3% (19/31), respectively. On the other hand, the prevalence rates were 0% (0/16) and 50% (8/16), respectively, in hepatitis B patients, 21.4% (3/14) and 71.4% (10/14), respectively, for hepatitis C patients, and 20.0% (9/45) and 57.8% (26/45), respectively, for non-A to C hepatitis patients (including 27 acute hepatitis patients, 5 fulminant patients and 13 chronic hepatitis patients). In this study, the prevalence rates determined by the Takahashi primer set tended to be 2-9 times higher than those determined using the Okamoto primer set. These results suggest that TTV infection is widespread among Japanese children. Furthermore, blood transfusion does not appear to be the major route of infection. The similar prevalence rates between control children and children with various types of hepatitis using the Takahashi primer system suggest that TTV infection does not play a direct causative role in the development of liver disease in children.

TT virus in Hungary: sequence heterogeneity and mixed infections

“…Genotype 1 is suspected to cause hepatitis [18]. Although the prevalence of TTV associated with acute and chronic hepatitis is higher than that in the general population, further studies are needed to demonstrate its possible role in the development of clinical hepatitis [15–17]. Recently, high TT virus load was found as an independent factor associated with the occurrence of hepatocellular carcinoma among patients with hepatitis C virus‐related chronic liver disease [19].…”

Fecal Excretion of a Novel Human Circovirus, TT Virus, in Healthy Children

“…Using these primers, Prescott and Simmonds demonstrated TTV prevalence as high as 83% in blood samples (18). A TTV prevalence of 92% has been demonstrated in blood samples by several investigators using T primers (2,23,25,26,30). Although our data revealed an overall TTV prevalence of 22.4%, T primers were more sensitive than NG primers (19.4 versus 10.5%).…”

“…The fecal-oral route of TTV transmission has been suggested by several investigators (16,20,25). However, no data have been reported on TTV in the feces of healthy children.…”

“…Currently available data on TTV prevalence are based on PCR amplification of TTV gene sequences from a variety of bodily fluids, such as blood, breast milk, saliva, and feces (1,2,11,19,23). The sensitivity of detecting TTV DNA by PCR is variable and is dependent on the primer pair (25,30). The first described and later modified primer pair, NG, is the most widely employed primer pair for amplification of TTV (17).…”

“…TTV has been suggested as an etiologic agent of non-A to -E hepatitis, but its role in liver disease is still unclear (14,25). TTV is widespread in the general population, with a reported prevalence of 1.9% in Scotland (22), 10% in the United States (2), 12% in Japan (17), 74% in Papua New Guinea, and 83% in Gambia (18).…”