Avian Disease Division, Animal and Plant Quarantine Agency, Gimcheon 39660, Gyeongsangbuk-do, Korea.
Veterinary Epidemiology Division, Animal and Plant Quarantine Agency, Gimcheon 39660, Gyeongsangbuk-do, Korea.
Viruses. 2022 Jul 22;14(8):1604. doi: 10.3390/v14081604.
Infectious bursal disease (IBD), caused by IBD virus (IBDV), threatens the health of the poultry industry. Recently, a subtype of genogroup (G) 2 IBDV named G2d has brought a new threat to the poultry industry. To determine the current status of IBDV prevalence in South Korea, active IBDV surveillance on 167 randomly selected broiler farms in South Korea from August 2020 to July 2021 was conducted. The bursas of Fabricius from five chickens from each farm were independently pooled and screened for IBDV using virus-specific RT-PCR. As a result, 86 farms were found to be infected with the G2d variant, 13 farms with G2b, and 2 farms with G3. Current prevalence estimation of IBDV infection in South Korea was determined as 17.8% at the animal level using pooled sampling methods. G2d IBDV was predominant compared to other genogroups, with a potentially high-risk G2d infection area in southwestern South Korea. The impact of IBDV infection on poultry productivity or infection susceptibility was also confirmed. A comparative pathogenicity test indicated that G2d IBDV caused severe and persistent damage to infected chickens compared with G2b. This study highlights the importance of implementation of regular surveillance programs and poses challenges for the comprehensive prevention of IBDV infections.
传染性囊病（IBD）由 IBD 病毒（IBDV）引起，对家禽业的健康构成威胁。最近，一种名为 G2d 的 IBDV 亚群（G）给家禽业带来了新的威胁。为了确定韩国 IBDV 的流行现状，2020 年 8 月至 2021 年 7 月对韩国 167 个随机选择的肉鸡场进行了主动 IBDV 监测。从每个农场的五只鸡的法氏囊独立汇集并使用病毒特异性 RT-PCR 筛选 IBDV。结果发现，86 个农场感染了 G2d 变异株，13 个农场感染了 G2b，2 个农场感染了 G3。使用汇集采样方法，目前韩国 IBDV 感染的流行率估计为 17.8%。与其他基因群相比，G2d IBDV 更为普遍，韩国西南部存在潜在的高风险 G2d 感染区。还证实了 IBDV 感染对家禽生产力或易感性的影响。比较致病性试验表明，与 G2b 相比，G2d IBDV 引起感染鸡的严重和持续损害。本研究强调了实施定期监测计划的重要性，并对 IBDV 感染的全面预防提出了挑战。
