| Swine hepatitis E which mainly exists as a latent infection in pigs is a zoonotic disease caused by swine hepatitis E virus. More and more studies have shown that SHEV genome is highly homologous to human hepatitis E virus genome, and SHEV can directly infect human cross species. Thus, SHEV have important significance on public health. In order to investigate the infection situation of SHEV and its characters in pigs of Jiangxi province, several aspects as follows have been studied in this research.1. According to the genomic sequences of SHEV which had been registered in the GenBank,2 pairs of degenerate primers were designed, and pig bile samples were used as materials to establish a rapid RT-nPCR assay for SHEV. Through this assay, even 2.5×10-5 ng SHEV RNA could be detected. The lung, liver, spleen, kidney, inguinal lymph nodes, blood, intestinal contents and feces sampled from pigs that tested bile positive were measured by this established method, and were all founded SHEV positive. 270 bile samples from 40～90 day-old pigs in some areas of Jiangxi province were collected for SHEV testing, and the test results showed that SHEV infection rate displayed seasonal changes:the SHEV infection rate in the first quarter (Jan, Feb, Mar) and the fourth quarter (Oct, Nov, Dec) of each year was the highest, and was relativily lower in the third quarter (Jul, Aug, Sep), and was the lowest in the second quarter (Apr, May, Jun).2. took human lung adenocarcinoma cells (A549) as the host cell, a swine hepatitis E virus was isolated from pig bile samples. This virus was named SHEV-JX, and its characters in A549 cells were preliminarily investigated. Bile sample was filtered with a 0.22μm filter before inoculated in A549 cells, and CPE began to appear after 3 blind passages (cell's refraction increased, gradually stretched to two ends and crushed. Dense arrangement transferred to loose arrangement, formed a crosslinked net work structure, and cells fell off), most obvious in the 5th～7th generation, began to weaken in the 8th generation, and backed to normal in the 10th generation. The replication situation of SHEV in each genetation from 1 to 10 was detected by a specific RT-nPCR method, and the results showed that SHEV could exist in A549 for only 7 generations.3. A partial genome sequence of SHEV-JX was isolated with SHEV-JX RNA and 6 degenerate primers designed according to SHEV genomic sequences which had been registered in the GenBank. The length of this sequence was 1629 bp, GenBank accession is JN052926, including a partial sequence of SHEV ORF2 (1551 bp) and a 3'UTR sequence (78 bp). Compared the partial sequence of SHEV-JX with sequences of SHEV in GenBank through the DNAstar software. The results indicated that, the genomic nucleotide of SHEV-JX show 74.6%-93.8% identity to other HEV isolates, the sequence of SHEV-JX was homologous to the SHEV typeⅣ.3'UTR of SHEV-JX was consisted of two stem-loop structures, in which the second stem-loop structure could be divided into two smaller stem-loop structures, and the secondary structure was affected by the length of poly (A).
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