Understanding Hepatitis
and the Appropriate Barrier Protection

(TTV) Transfusion Transmitted Virus DEFINITION This is the seventh hepatitis virus discovered called transfusion-transmitted virus (TTV). It is a single-stranded DNA virus with 3739 nucleotides. TTV has been implicated in post transfusion hepatitis.91 CLINICAL MANIFESTATIONS The clinical manifestations that might present include: Anemia Leucopenia Thrombocytopenia.92 INCUBATION PERIOD There is not substantial evidence yet to determine the incubation period for TTV.93 CAUSE TTV has been found in populations all over the world. TTV is an unenveloped, single stranded DNA virus with 3739 nucleotides. Two genetic groups have been identified, differing by 30% in nucleotide sequences. TTV DNA was detected in 47% of patients with fulminant non-A-G hepatitis and 46% of patients with chronic liver diseases of unknown etiology.94 The result of this study indicates that TTV may be the cause of some cryptogenic liver diseases. Studies have shown that the prevalence of infection ranges from 1.9 to 36% among blood donors, from 11.5 to 71% in hemodialysis patients, from 47 to 82% among patients with non-A, non-B or non-C fulminant hepatic failure, and the most elevated percentage is found in hemophiliacs.95 DIAGNOSIS Commercial tests are not yet available to screen for TTV infections. This is detected by a Polymerase Chain reaction test. POST-EXPOSURE PROPHYLAXIS There is no post exposure prophylactic at this time. LONG-TERM EFFECTS Transfusion Transmitted Virus is a newly described virus that is implicated in the development of fulminant hepatitis and chronic liver disease. TRANSMISSION TT Virus has been shown to be transmitted via the parenteral (blood) route. Hemophiliacs and recipients of blood transfusions are at greater risk to have TTV than other people. It is indeterminate by what other routes transmission of this virus can occur. The virus has been detected in other body fluids, such as saliva, as well as in feces, it is thought that the virus may be transmissible by the fecal-oral route and maybe also by saliva droplets. This virus is more prevalent in areas with increased promiscuity and so it is suspect, to be sexually transmitted. It has also been detected in breast milk but it is unclear if it has been transmitted by mother-to-child.96,97,98 WHO IS AT RISK? Overall, high-risk groups for contraction of this virus include hemophiliacs, hemodialysis patients, and transplant recipients. It is unclear what the clinical significance is for any of these groups.99 TREATMENT Unfortunately routes of transmission have not been well defined for this virus, therefore prevention and management are difficult to determine as well at this time. INFECTION CONTROL AND PREVENTION Currently, scientific efforts have been focused on determining what TTV does, not preventing its spread or treating it. Prevention efforts will become more important if we determine that TTV causes or worsens human disease.100 Because of the uncertainty of transmission of this disease, always follow routine Standard Precautions that include the following: Hand Washing Wash hands immediately after gloves are removed, between patient contacts, and when otherwise indicated to avoid transfer of microorganisms to other patients or environments. Gloves Wear gloves manufactured with proper barrier protection materials when touching blood, body fluid, secretions, excretions, and contaminated items; put on clean gloves just before touching mucous membranes and nonintact skin. Change gloves between tasks and procedures on the same patient after contact with material that may contain a high concentration of microorganisms. Remove gloves promptly after use, before touching noncontaminated items and environmental surfaces, and before going to another patient, and wash hands immediately to avoid transfer of microorganisms to other patients of environments. Masks, Eye Protection, Face Shields Wear a mask, (standard surgical mask) and eye protection or a face shield to protect mucous membranes of the eyes, nose, and mouth during procedures and activities that are likely to generate splashes or sprays. VACCINE RECOMMENDATIONS There is no vaccine at this time for TT virus FACTS, STATISTICS, AND TRENDS Transfusion Transmitted Virus is a relatively new virus becoming widely known in 1997 in patients with fulminant hepatitis and chronic liver disease of unknown etiology.101 TTV-Virus is a new virus first reported in Japan in 1997 by T. Nishizawa. It was found in patients with fulminant hepatitis and chronic liver disease of unknown etiology.102 In Taiwan, TTV is prevalent in the general population as well as in patients with liver diseases. TTV plays an insignificant role in acute fulminant and non-fulminant hepatitis. TTV does not appear to cause hepatitis on its own.103 So much is still unknown about this disease, it continues to be researched.

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