[Epidemiological survey on the infection of hepatitis E virus among pigs in Henan province].

Objective: To investigate hepatitis E virus (HEV) infection among pigs in Henan province.

Methods: A total of 623 swine sera, collected from 5 districts, were divided into two groups, under 3-month of age and over 3-month of age. They were tested for HEV antigen and antibody by using ELISAs, respectively.

[A study on the prevalence rates of human immunodeficiency virus, hepatitis B virus and hepatitis C virus infections in intravenous drug users].

Objective: To study HIV, HBV and HCV infections in intravenous drug users.

Methods: 2025 blood samples from intravenous drug users were collected from Sichuan, Hunan, Guangxi and Xinjiang regions, and tested for anti-HIV, anti-HCV, HBsAg using enzyme-linked immuno-sobent assays (ELISAs).

Results: The positive rates of anti-HIV,anti-HCV and HBsAg were14.

[Establishment of the reference panel for HIV RNA].

Objective: To establish a national reference panel for HIV RNA diagnostic reagents.

Methods: Sera from patients with HIV infection and healthy blood donors were collected and tested for HIV and HCV antibodies and HBsAg by using ELISA. The HIV antibody positive samples with ELISA were confirmed with HIV Blot 2.

[Capacity of HIV enzyme immunoassay diagnostic kits to detect antibodies against different genotypes of HIV].

Objective: To investigate the capacity of commercial HIV enzyme immunoassay (EIA) diagnostic kits to detect antibodies against different genotypes of HIV.

Methods: HIV RNA was detected with RT-PCR from samples positive for HIV antibody. The purified PCR products were sequenced directly and the genotypes of HIV from samples were analyzed.