Hepatitis E virus: molecular virology, clinical features, diagnosis, transmission, epidemiology, and prevention.

Hepatitis E virus (HEV), the sole member of the genus Hepevirus in the family of Hepeviridae, is the major cause of several outbreaks of waterborne hepatitis in tropical and subtropical countries and of sporadic cases of viral hepatitis in endemic and industrialized countries. Transmission of HEV occurs predominantly by the fecal-oral route although parenteral and perinatal routes have been implicated. The overall death rate among young adults and pregnant women is 0.

Verses, viruses, and the vulnerability of the blood supply in industrialized countries.

In the last 30 years, tremendous progress in identifying transfusion-transmitted viruses such as HBV, HCV, and HIV in industrialized countries has been achieved. Currently, the residual risk of transmitting these viruses through transfusion is very low especially after the introduction of "minipool" nucleic acid-amplification tests. Despite these major technical advances, there remains a legitimate concern as to the transmission of other blood-borne infectious agents through blood transfusion.

Genetic diversity of hepatitis B virus strains derived worldwide: genotypes, subgenotypes, and HBsAg subtypes.

Sequences of 234 complete genomes and 631 hepatitis B surface antigen genes were used to assess the worldwide diversity of hepatitis B virus (HBV). Apart from the described two subgenotypes each for A and F, also B, C, and D divided into four subgenotypes each in the analysis of complete genomes supported by significant bootstrap values. The subgenotypes of B and C differed in their geographical distribution, with B1 dominating in Japan, B2 in China and Vietnam, B3 confined to Indonesia, and B4 confined to Vietnam, all strains specifying subtype ayw1.

Quantitation of hepatitis B surface antigen by an automated chemiluminescent microparticle immunoassay.

A fully automated chemiluminescent microparticle immunoassay (Architect HBsAg QT) was used for the detection and quantitation of hepatitis B surface antigen (HBsAg). The assay is capable of processing up to 800 HBsAg tests per hour. The concentration of HBsAg is determined by utilizing a previously generated Architect HBsAg calibration curve.

Selectively primed adaptive driver RDA (SPAD-RDA): an improved method for subtractive hybridization.

A modification of the Representational Difference Analysis (RDA) method for subtractive hybridization, termed Selectively Primed Adaptive Driver (SPAD) RDA, is described. It differs from conventional RDA primarily in the manner by which initial driver (D) and tester (T) amplicon complexities are determined, and by optimizing the composition of D with respect to T for each round of subtraction. Total nucleic acid is extracted from serum or plasma and converted to double-stranded DNA/cDNA.