EVIDENCE FOR THE IN UTERO TRANSMISSION OF PORCINE TORQUE TENO VIRUSES (TTVS)

摘要

IntroductionThe TTVs are unculturable single stranded, circularized DNA viruses classified as Anelloviruses. Species-specific TTVs are widely distributed in both humans & animals; at least 5 distinct genogroups of human TTVs are known 1_3. Positive associations have not been found between TTV status & disease. The TTVs are thought to be "normal flora". Swine are also infected with their own TTVs 4"5; 2 pig geno-groups (g), 1 & 2 are known5. Swine TTVs are widely distributed in pigs; they are also con-sidered non-pathogenic. In humans, TTVs may be transmitted by blood products. However, the high prevalence of TTV in humans suggests that a more effective means of transmission for these viruses must exist; the most likely route is fecal-oral transmission & this has been experimentally demonstrated. As well, mother-to-infant trans-mission6 has been documented suggesting that in utero transmission must also occur.