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What is TTV?

Torque Teno Virus (TTV) is a small, non-enveloped virus belonging to the Anelloviridae family. This circular, single-stranded DNA virus is highly prevalent in humans and is found in diverse body fluids, including blood, saliva, and semen.

Despite its widespread presence in 90% of normal, healthy adults, TTV has not been linked to specific diseases, making its clinical significance unclear. A number of studies suggest that TTV may act as a marker of immune status rather than a pathogen, with higher viral loads observed in immunocompromised individuals, such as organ transplant recipients and HIV patients. The prevalence of TTV in solid organ transplant recipients is up to 99% depending on time post-transplant.

TTV viral load monitoring is a promising tool in clinical diagnostics, providing critical information for managing patient health, particularly in those with compromised immune systems, including solid organ transplant recipients.

TTV viral load monitoring is beneficial for both infection and rejection risk monitoring in solid organ transplant recipients. The analyte, viral DNA, is stable, and the method of analysis qPCR) has excellent precision and a large dynamic range.

TTV viral load in plasma indicates the intensity of host immunosuppression and is associated with the risk of allograft rejection and infectious disease.

  • Higher TTV viral load is associated with a higher risk of infection, lower risk of Rejection
  • Lower TTV viral load is associated with a higher risk of rejection, lower risk of infection

Contact us to learn more about the TTV assay

First in Testing Innovation

Safeguarding the Health of Solid Organ Transplant Recipients

At the forefront of medical innovation, Eurofins Viracor leads the way with the groundbreaking TTViWATCH Torque Teno Virus qPCR viral load assay. Now available in the U.S., this innovative test has the power to revolutionize patient care by providing essential information on infection and rejection risks, vital for protecting the well-being of solid organ transplant recipients with weakened immune systems. Equipping healthcare professionals with this invaluable diagnostic tool ensures improved outcomes and enhanced quality of life for transplant recipients. Take action now to make TTV testing a standard practice in transplant medicine.

TTV - Torque Teno Virus

Risk Stratification for Solid Organ Transplant Recipients

Improved and standardized methods are needed to monitor the net state of immunosuppression in solid organ transplant recipients.

Torque Teno Virus (TTV) is a non-pathogenic virus that has been widely studied as a biomarker of the net state of immunosuppression.

  • Increases in TTV viral load have been widely correlated with a decreased risk of allograft rejection and an increased risk of infections.
  • For each 10-fold increase in TTV load, rejection risk decreases by 25% and infection risk increases by 4%
  • The proposed TTV target range for balanced immunosuppression is 106 to 108 copies/mL.
TTV Risk Stratification Diagram

Doberer K, Schiemann M, Strassl R, Haupenthal F, Dermuth F, Görzer I, Eskandary F, Reindl-Schwaighofer R, Kikić Ž, Puchhammer-Stöckl E, Böhmig GA, Bond G. Torque teno virus for risk stratification of graft rejection and infection in kidney transplant recipients-A prospective observational trial. Am J Transplant. 2020 Aug;20(8):2081-2090. doi: 10.1111/ajt.15810. Epub 2020 Mar 8. PMID: 32034850; PMCID: PMC7496119.

Irene Görzer, Frederik Haupenthal, Fabrizio Maggi, Fanny Gelas, Dorian Kulifaj, Ludovic Brossault, Elisabeth Puchhammer-Stöckl, Gregor Bond, Validation of plasma Torque Teno viral load applying a CE-certified PCR for risk stratification of rejection and infection post kidney transplantation, Journal of Clinical Virology, Volume 158, 2023, 105348, ISSN 1386-6532,

van Rijn AL, Roos R, Dekker FW, Rotmans JI, Feltkamp M. Torque teno virus load as marker of rejection and infection in solid organ transplantation - A systematic review and meta-analysis. Rev Med Virol. 2023 Jan;33(1):e2393. doi: 10.1002/rmv.2393. PMID: 36056751; PMCID: PMC10078304.

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