猪繁殖与呼吸综合征病毒 2 型(PRRSV-2)在美国猪业中的遗传多样性和野生型及疫苗株的发生情况。
Porcine reproductive and respiratory syndrome virus 2 (PRRSV-2) genetic diversity and occurrence of wild type and vaccine-like strains in the United States swine industry.
机构信息
Department of Veterinary Population Medicine, University of Minnesota, Saint Paul, MN, United States of America.
Facultad de Recursos Naturales, Departamento de Ciencias Veterinarias y Salud Pública, Universidad Católica de Temuco, Temuco, Araucanía, Chile.
出版信息
PLoS One. 2021 Nov 19;16(11):e0259531. doi: 10.1371/journal.pone.0259531. eCollection 2021.
Porcine reproductive and respiratory syndrome virus genotype 2 (PRRSV-2) genetic diversity in the U.S. was assessed using a database comprising 10 years' worth of sequence data obtained from swine production systems routine monitoring and outbreak investigations. A total of 26,831 ORF5 PRRSV-2 sequences from 34 production systems were included in this analysis. Within group mean genetic distance (i.e. mean proportion of nucleotide differences within ORF5) per year according to herd type was calculated for all PRRSV-2 sequences. The percent nucleotide difference between each sequence and the ORF5 sequences from four commercially available PRRSV-2 vaccines (Ingelvac PRRS MLV, Ingelvac PRRS ATP, Fostera PRRS, and Prevacent PRRS) within the same lineage over time was used to classify sequences in wild-type or vaccine-like. The mean ORF5 genetic distance fluctuated from 0.09 to 0.13, being generally smaller in years in which there was a relative higher frequency of dominant lineage. Vaccine-like sequences comprised about one fourth of sequences obtained through routine monitoring of PRRS. We found that lineage 5 sequences were mostly Ingelvac PRRS MLV-like. Lineage 8 sequences up to 2011 were 62.9% Ingelvac PRRS ATP-like while the remaining were wild-type viruses. From 2012 onwards, 51.9% of lineage 8 sequences were Ingelvac PRRS ATP-like, 45.0% were Fostera PRRS-like, and only 3.2% were wild-type. For lineage 1 sequences, 0.1% and 1.7% of the sequences were Prevacent PRRS-like in 2009-2018 and 2019, respectively. These results suggest that repeated introductions of vaccine-like viruses through use of modified live vaccines might decrease within-lineage viral diversity as vaccine-like strains become more prevalent. Overall, this compilation of private data from routine monitoring provides valuable information on PRRSV viral diversity.
在美国,使用包含 10 年猪生产系统常规监测和疫情调查获得的序列数据的数据库,评估了猪繁殖与呼吸综合征病毒 2 型(PRRSV-2)的遗传多样性。该分析共纳入了 34 个生产系统中 26831 个 ORF5 PRRSV-2 序列。根据畜群类型,计算了每年所有 PRRSV-2 序列的组内平均遗传距离(即 ORF5 内核苷酸差异的平均比例)。根据同一谱系内的四个市售 PRRSV-2 疫苗(Ingelvac PRRS MLV、Ingelvac PRRS ATP、Fostera PRRS 和 Prevacent PRRS)的 ORF5 序列,计算了每个序列与 ORF5 序列之间的核苷酸差异百分比,用于将序列分类为野生型或疫苗型。野生型序列约占通过 PRRS 常规监测获得的序列的四分之一。我们发现,谱系 5 序列主要与 Ingelvac PRRS MLV 相似。2011 年之前的谱系 8 序列有 62.9%与 Ingelvac PRRS ATP 相似,其余为野生型病毒。2012 年以后,谱系 8 序列中有 51.9%与 Ingelvac PRRS ATP 相似,45.0%与 Fostera PRRS 相似,只有 3.2%为野生型。谱系 1 序列在 2009-2018 年和 2019 年分别有 0.1%和 1.7%与 Prevacent PRRS 相似。这些结果表明,通过使用改良活疫苗反复引入疫苗型病毒可能会降低谱系内病毒多样性,因为疫苗型菌株变得更为流行。总的来说,本研究通过常规监测收集的私人数据,为 PRRSV 病毒多样性提供了有价值的信息。