Virologic, immunologic and biochemical events during the course of experimental hepatitis A virus infection in chimpanzees inoculated intravenously with human HAV, strain HLD2. ALT, alanine aminotransferase. (Adapted from reference 157 with permission of the publisher.)

Phylogenetic analysis of 3,582 HAV isolates in the VP1/P2B region (315-bp fragment). The dendrogram (unweighted-pair group method using average linkages) was created by using Kimura's two-parameter model. Isolates were obtained from the United States (n = 2,190) and other parts of the world. The U.S. specimens included specimens from hepatitis A cases from CDC's Sentinel Counties Study of Acute Viral Hepatitis (11, 170), published and unpublished outbreak investigations (30, 63, 112), and others submitted to CDC for investigation. Specimens from the U.S.-Mexico Border Infectious Disease Surveillance (BIDS) project (258) were also included and represented cases primarily from the United States. Specimens from other countries include those from Mexico, Brazil, Israel, Jordan, Egypt, Moldova, and Kazakhstan and were submitted to CDC as part of outbreak or epidemiologic investigations. Sequences from GenBank (Italy, Norway, Spain, Tunisia, and Japan) were also included in the analysis. Only unique sequence patterns are shown in the tree. Genotypes and subgenotypes are indicated on the branches, and the geographical locations of case patients are indicated in different colors.

Schematic representation of the HAV genome organization, translation products, and regions used for amplification. The area encoding the polyprotein is represented by solid box and the proposed cleavage sites by vertical lines. Regions commonly used for PCR amplifications are as follows: region 1, C terminus of VP3 region (nt 2,020 to nt 2,226); region 2, N terminus of VP1 region (nt 2,172 to nt 2,415); region 3, VP1/P2A junction region (nt 2,984 to nt 3,217); region 4, VP1-P2B region (nt 2,896 to nt 3,289); region 5, entire VP1 region (nt 2,172 to nt 3,125); and region 6, VP3-P2B region (nt 2,133 to nt 3,289). Nucleotide position numbering is according to the HM175 sequence (46).