RESUMO
In September 2018, classical swine fever reemerged in Japan after 26 years, affecting domestic pigs and wild boars. The causative virus belongs to the 2.1 subgenotype, which caused repeated outbreaks in eastern and Southeast Asia. Intensive surveillance of swine and vaccination of wild boars will help control and eradicate this disease in Japan.
Assuntos
Vírus da Febre Suína Clássica , Peste Suína Clássica/epidemiologia , Peste Suína Clássica/virologia , Animais , Peste Suína Clássica/história , Vírus da Febre Suína Clássica/classificação , Vírus da Febre Suína Clássica/genética , Vírus da Febre Suína Clássica/isolamento & purificação , Genes Virais , História do Século XXI , Japão/epidemiologia , Filogenia , Vigilância em Saúde Pública , RNA Viral , SuínosRESUMO
Classical swine fever (CSF) continues to be a devastating infectious disease for the swine industry in China and commonly exists as wild or atypical types. From June 3rd to October 3rd, 2018, outbreaks of typical CSF cases with mortality rates of 42-86% occurred in 11 swine herds in five cities of Guangdong province, and were confirmed by RT-PCR. Phylogenetic analyses based on the nucleotide sequences of full-length E2 genes showed that the CSFV isolates collected in Guangdong, 2018 grouped into sub-subgenotype 2.1c and formed a separate clade from previously identified 2.1c isolates. Sequence comparison further confirmed the distance between the novel emergent and previously identified 2.1c isolates, with shared 94.5-98.2% and 97.8-99.7% identities at the nucleotide and amino acid levels respectively. Furthermore, 2.1c isolates collected in 2018 from Guangdong province contained a unique amino acid substitution (K174R) in the E2 protein in comparison with other 2.1c representative strains and CSFV 2.1, 2.2, 2.3 strains. Of note, the novel emergent 2.1c isolates are neutralized by sera from C-strain vaccinated sows, indicating that C-strain is still efficacious for protection against field isolates of CSFV.
Assuntos
Vírus da Febre Suína Clássica/classificação , Vírus da Febre Suína Clássica/genética , Peste Suína Clássica/epidemiologia , Peste Suína Clássica/virologia , Genótipo , Sequência de Aminoácidos , Substituição de Aminoácidos , Animais , Anticorpos Neutralizantes , Anticorpos Antivirais/imunologia , Biópsia , China/epidemiologia , Peste Suína Clássica/diagnóstico , Peste Suína Clássica/história , Vírus da Febre Suína Clássica/imunologia , Vírus da Febre Suína Clássica/isolamento & purificação , Surtos de Doenças , Evolução Molecular , Genes Virais , Geografia Médica , História do Século XXI , Filogenia , SuínosRESUMO
Classical swine fever virus (CSFV), porcine reproductive and respiratory syndrome virus (PRRSV) and porcine circoviruses (PCV2 and PCV3) are economically important swine viruses that cause reproductive failure and/or respiratory symptoms in pigs. However, the co-infection status of these viruses in Chinese swine herds is not well clarified. In this study, we evaluated the co-infection of these four viruses in 159 pigs collected from 63 herds in eight regions of China from 2016 to 2018. CSFV, PRRSV, PCV2 and PCV3 were detected in 14, 56, 43 and 4 of the pigs, respectively. The percentage of singular infections was 32.71%, while the percentages of dual infections and multiple infections were 15.72% and 3.15%, respectively. The E2 of CSFV, ORF5 of PRRSV, ORF2s of PCV2 and PCV3 from all positive samples were determined and used for phylogenetic analyses. E2-based phylogenetic tree showed that all 14 CSFVs identified in this study belong to 2.1b subtype. ORF5-based phylogenetic tree showed that PRRSV2 is predominant in China while PRRSV1 can also be detected. In addition, 35, 16, 4 and 1 of our PRRSVs are clustered with highly pathogenic PRRSV2, NADC30-like PRRSV2, classical PRRSV2 and PRRSV1, respectively. ORF2-based phylogenetic trees showed that our PCVs are grouped with 2 PCV2 subtypes (PCV2d and PCV2b) and 3 PCV3 subtypes (PCV3a, PCV3b and PCV3c), respectively. Our results provide the latest co-infection status and the diversity of four important swine viruses in Chinese swine herds, which is beneficial for understanding the epidemiology of these viruses.
Assuntos
Infecções por Circoviridae/veterinária , Circovirus , Vírus da Febre Suína Clássica , Peste Suína Clássica/epidemiologia , Coinfecção , Síndrome Respiratória e Reprodutiva Suína/epidemiologia , Vírus da Síndrome Respiratória e Reprodutiva Suína , Animais , China/epidemiologia , Circovirus/classificação , Circovirus/genética , Peste Suína Clássica/história , Peste Suína Clássica/virologia , Vírus da Febre Suína Clássica/classificação , Vírus da Febre Suína Clássica/genética , História do Século XXI , Tipagem de Sequências Multilocus , Filogenia , Síndrome Respiratória e Reprodutiva Suína/história , Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/classificação , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , SuínosRESUMO
The most important characteristics and the distribution of the viruses of African swine fever and hog cholera are reviewed. Both viruses were probably present simultaneously in South Africa in the first two decades of the century. While hog cholera was eradicated by 1918, African swine fever persists to the present day because it has a different epizootiology. The role played by wild pigs and the argasid tick (Ornithodoros moubata porcinus) in the epizootiology of African swine fever is discussed and an account of the outbreaks of the disease in South Africa from 1926 to 1974 is given. It appears that the disease in the Transvaal has had a cyclic occurrence.
Assuntos
Peste Suína Clássica , Animais , Peste Suína Clássica/epidemiologia , Peste Suína Clássica/história , Peste Suína Clássica/transmissão , História do Século XX , SuínosAssuntos
Legislação Veterinária/história , Medicina Veterinária/história , Animais , Brucelose Bovina/história , Bovinos , Doenças dos Bovinos/história , Peste Suína Clássica/história , Encefalomielite Equina/veterinária , Inspeção de Alimentos , Febre Aftosa/história , História do Século XIX , História do Século XX , História Antiga , Doenças dos Cavalos/história , Cavalos , Legislação de Medicamentos/história , Carne , México , Pleuropneumonia Contagiosa/história , Escabiose/veterinária , Infecção por Mosca da Bicheira/veterinária , Ovinos , Doenças dos Ovinos/história , Suínos , Tuberculose Bovina/história , Estados Unidos , Vacinação/veterinária , Exantema Vesicular de Suínos/históriaRESUMO
A review on classical swine fever (CSF) research and vaccine production is given about four historical periods (1924-1948, 1949-1969, 1970-1991, since 1992). Similar as to research on foot and mouth disease, applied topics as diagnosis, pathogenesis, epidemiology and control represented the CSF research over many years. The development of vaccines and application procedures, e.g. oral and aerogenic immunisation and combined vaccines for large pig farms were the prominent investigations between 1950 and the middle of 1980s. After being reduced in the first years after affiliation to the Federal Research Centre for Virus Diseases of Animals, CSF is one of the main topics of the research on the Isle of Riems, not at least because nowadays the German National Reference Laboratory for CSF was established on the Island.