Fitzner A, Niedbalski W
Pol J Vet Sci. 2016 Sep 1;19(3):597-607. doi: 10.1515/pjvs-2016-0075.
Seroprevalence studies of RHDV antibodies in domestic rabbits were conducted between 2008-2014. A total of 12,169 sera from the provinces of central, southern and south-east Poland, including 7,570 samples collected from mixed-breed rabbits reared in smallholder farms and nearly 4,600 sera taken mainly from unvaccinated rabbits kept in industrial farms, were examined using ELISA tests. Additionally, cross-reactivity of selected tested and control archival sera using both classic RHDV and RHDVa antigens was determined by HI assay. The overall seroprevalence was 13.3%. In rabbits with unkown history of immunisation or RHD infection which came from small farms, RHDV antibodies were detected in 6.1% ranging between 1.0% to 17.2% of animals. In rabbits of the same group, but with a declared vaccination status, or confirmed exposure to an infectious virus, or coming from exposed females, the seroprevalence ranged from 83% to 100%. Among unvaccinated meat rabbits aged 71 to 90 days from industrial farms, low (1.85%, 4.17%, 11%), medium (34%, 54%) or high rates (98.7%) of seropositivity were detected. The seroconversion recorded in adult vaccinated females from industrial farms was 70% and 95%. Generally, the antibody levels examined by ELISAs and HI were comparable. However, a number of sera from the rabbits from small farms, as well as archival sera, showed clear differences. Several-fold differences in antibody titers, evidenced mainly in the postoutbreak sera, indictaed the contact of animals with RHDVa antigen. The overall results of the survey revealed a great proportion of seronegative rabbits potentially highly susceptible to RHD infection. In combination with the emergence of a novel pathogenic RHD virus type (RHDV2), it poses a severe risk of a next wave of fatal disease cases spreading in the native population of domestic rabbits, especially in farms with a traditional system of husbandry.
2008年至2014年间，对家兔进行了兔病毒性出血症（RHDV）抗体血清流行率研究。使用酶联免疫吸附测定（ELISA）试验检测了来自波兰中部、南部和东南部省份的总共12,169份血清，其中包括从小型农户饲养的杂种兔采集的7,570份样本，以及主要从未接种疫苗的、饲养在工业化养殖场的家兔采集的近4,600份血清。此外，通过血凝抑制（HI）试验确定了使用经典RHDV和RHDVa抗原对选定的检测血清和对照存档血清的交叉反应性。总体血清流行率为13.3%。在来自小型农场、免疫或RHD感染史不明的家兔中，检测到RHDV抗体的比例为6.1%，动物个体比例在1.0%至17.2%之间。在同一组但有明确疫苗接种状态、或确认接触过传染性病毒、或来自接触过病毒的母兔的家兔中，血清流行率在83%至100%之间。在来自工业化养殖场、71至90日龄的未接种疫苗的肉兔中，检测到低（1.85%、4.17%、11%）、中（34%、54%）或高（98.7%）的血清阳性率。在来自工业化养殖场的成年接种疫苗母兔中记录的血清转化率分别为70%和95%。一般来说，通过ELISA和HI检测的抗体水平具有可比性。然而，一些来自小型农场家兔的血清以及存档血清显示出明显差异。抗体滴度的几倍差异主要在疫情后血清中得到证实，表明动物与RHDVa抗原发生了接触。调查的总体结果显示，很大比例的血清阴性家兔可能对RHD感染高度易感。再加上新型致病性兔病毒性出血症病毒（RHDV2）的出现，这对家兔本地种群，尤其是传统养殖系统的养殖场中，下一波致命疾病病例的传播构成了严重风险。
