T.T. VIRUS INFECTION AND NON-A-G HEPATITIS

Abstract

In 1997, a new virus was isolated from the serum of a Japanese patient who developed post transfusion hepatitis and was not related to any of the known hepatitis viruses. The virus was named TIV after the initials of the patient from whom it was first isolated.

TIV was found to be a single stranded unenveloped DNA virus and was proposed to be a member of a new virus family that infects humans, tentatively named the circinoviridae family.

As the virus was first isolated from a patient with post transfusion hepatitis, the major route of transmission was assumed to be parenteral. However, the virus is also transmitted via the faeco-oral route and it is also, transmitted in utero and via breast milk.

Epidemiological studies have shown the virus to be widely distributed in different populations with parenteral risk of exposure as haemodialysis patients, intra venous drug users and haemophilics. The virus was also, detected at a lower incidence in voluntary blood donors.

Although, TTV was isolated from the serum of a posttransfusion hepatitis patient, yet the exact hepatitis inducing capacity of TIV needs to be evaluated.