TT virus infection in children and adults who visited a general hospital in the south of Brazil for routine procedure

TT virus (TTV) is a newly described nonenveloped human virus, with a circul ar, negative-stranded DNA genome, that was first identified in the blood of a patient with posttransfusion hepatitis of unknown etiology. PCR primers and conditions used for TTV DNA amplification may greatly influence the lev el of TTV detection in serum. Three PCR assays, with different regions of t he genome as targets, were used to zest TTV DNA in 130 sera from children a nd adults visiting a hospital in the south of Brazil, most of them for rout ine procedure. Forty-four percent of adult sera and 73% of sera from childr en aged 0-10 years were TTV positive with at least one PCR assay. However. the three assays were able to detect only 33%, 35% and 70% of the total pos itive samples. Our results showed a high prevalence of TTV infection in the south of Brazil, particularly among young children, and confirmed the nece ssity of performing several PCR assays to assess the hue TTV prevalence in a determined population.