Development of an RT-PCR for rabbit hemorrhagic disease virus (RHDV) and the epidemiology of RHDV in three eastern provinces of China.

Reverse transcriptase polymerase chain reaction (RT-PCR) for the diagnosis of rabbit hemorrhagic disease virus (RHDV) was developed by examining sensitivity and specificity. Samples from rabbits infected with rabbit hemorrhagic disease (RHD) were examined to investigate the distribution of the virus in the body. The results showed that the RT-PCR method had good specificity. The sensitivity of the RT-PCR was 1 x 10(4) times higher than that of the hemagglutination assay (HA). RT-PCR was able to detect RHDV in all viscera, but not in feces. In the second part of the study, in order to investigate the prevalence of RHDV, 400 meat samples from the Entry-exit Inspection and Quarantine Bureau and 512 nasal secretion samples from rabbits in three provinces of China were collected and tested by RT-PCR. The results showed significant differences in the prevalence of RHDV in rabbits of different ages, but no significant differences among different provinces and years. Some random isolates were sequenced and compared. The homology of sequences among three new isolates and other isolates ranged between 93.7% and 99.6%. It is recommended that RHD vaccine should be used in China to protect rabbits against RHDV.