Identification of 2 novel isolates of hepatitis E virus in Argentina

Hepatitis E virus (HEV) has been identified in 2 Argentine patients with acute hepatitis who reported no history of travel to regions in which HEV is considered endemic. These isolates are the first to be identified in South America. By use of degenerate primers from open reading frames 1 and 2, HEV sequences were obtained from these patients' serum and compared with published HEV sequences. The Argentine isolates are different from all previously identified HEV isolates and are most closely related to each other. The Argentine isolates are distinct from the most geographically related isolate from Mexico as well as isolates from other endemic (China, Southeast Asia, and India) and nonendemic (the United States and Europe) regions. Phylogenetic analysis indicate that the Argentine isolates represent a new genotype of HEV, genotype 8, distinct from the Burmese-like genotype 1, Mexican genotype 2, US genotype 3, Chinese/Taiwan genotype 4, and European genotypes 5-7.