Route of TT virus infection in children.
TT virus (TTV) is a novel viral agent, detected recently in non-A to E hepatitis cases. Little is known about its natural history or routes of transmission in childhood. For the detection of serum TTV DNA, semi-nested polymerase chain reaction (PCR) was carried out using TTV-specific primers and TTV nucleotide sequences were determined by the dideoxy chain-mediated termination method. Five of the 70 children studied (including 20 hepatitis B virus [HBV] carriers, 40 children born to HBV carrier mothers and 10 children born to hepatitis C virus [HCV] carrier mothers) had serum TTV DNA. Three of the 5 children had siblings (4 in total), so that a total of 9 children were studied to determine the time of initial serum TTV DNA detection. In the 8 seropositive children, the time of serum TTV DNA detection ranged from 6 to 14 months after birth, and TTV DNA persisted thereafter throughout the follow-up period. The TTV DNA-negative child was assessed most recently at 6 months of age. TTV DNA was detected in only 2 of the 4 mothers tested (families 2 and 3). When 271-bp TTV DNA fragments from each of the 8 children were sequenced, the degree of homology between siblings in families 1-3 was 100%, 99.5%, and 92.3%, respectively. The degree of homology between child-mother pairs of families 2 and 3 was 99.5-100% and 62. 6-63.9%, respectively. The distribution of different TTV strains was consistent within families, except for family 3. None of the TTV-infected children had elevated levels of alanine aminotransferase or clinical signs of liver disease.
Sugiyama
K
K
Department of Pediatrics, Nagoya City University Medical School, Nagoya, Japan.
Goto
K
K
Ando
T
T
Mizutani
F
F
Terabe
K
K
Kawabe
Y
Y
Wada
Y
Y
D000293:Adolescent; D000328:Adult; D002353:Carrier State / Q000453:epidemiology / Q000821:virology; D002648:Child; D002675:Child, Preschool; D004266:DNA Virus Infections / Q000635:transmission* / Q000821:virology*; D004267:DNA Viruses / Q000235:genetics / Q000302:isolation & purification*; D004279:DNA, Viral / Q000032:analysis; D018562:Disease Transmission, Infectious; D005260:Female; D006801:Humans; D007223:Infant; D007564:Japan; D016133:Polymerase Chain Reaction; D011247:Pregnancy; D016415:Sequence Alignment
D004279:DNA, Viral