RESUMO
The purpose of this work was to characterize 47 Escherichia coli strains isolated from 32 pigs diagnosed with postweaning diarrhea and three pigs with edema disease by PCR. Forty two (95.5 %) of the strains isolated from diarrheic pigs were characterized as enterotoxigenic E. coli (ETEC) and 2 (4.5 %) as Shiga toxin-producing E. coli (STEC). Fourteen (33.3 %) ETEC strains were positive for est/estII/fedA genes. The most complex genotype was eltA/estI/faeG/aidA. Strains isolated from pigs with ED were classified as porcine STEC and were stx2e/aidA carriers. Eleven (25 %) strains carried the gene encoding adhesin protein AIDA-I. However, genes coding for F5, F6, F41, intimin and Paa were not detected. The development of vaccines generating antibodies against prevalent E. coli adhesins in Argentina could be useful for the prevention of PWD and ED.
Assuntos
Diarreia/veterinária , Edematose Suína/microbiologia , Escherichia coli Enterotoxigênica/genética , Infecções por Escherichia coli/veterinária , Proteínas de Escherichia coli/genética , Genes Bacterianos , Escherichia coli Shiga Toxigênica/genética , Doenças dos Suínos/microbiologia , Adesinas de Escherichia coli/genética , Animais , Argentina/epidemiologia , Diarreia/epidemiologia , Diarreia/microbiologia , Surtos de Doenças , Edematose Suína/epidemiologia , Escherichia coli Enterotoxigênica/isolamento & purificação , Enterotoxinas/genética , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Genótipo , Escherichia coli Shiga Toxigênica/isolamento & purificação , Sus scrofa , Suínos , Doenças dos Suínos/epidemiologia , DesmameRESUMO
Sporadic outbreaks of human H3N2 influenza A virus (IAV) infections in swine populations have been reported in Asia, Europe and North America since 1970. In South America, serological surveys in pigs indicate that IAVs of the H3 and H1 subtypes are currently in circulation; however, neither virus isolation nor characterization has been reported. In November 2008, an outbreak of respiratory disease in pigs consistent with swine influenza virus (SIV) infection was detected in Argentina. The current study describes the clinical epidemiology, pathology, and molecular and biological characteristics of the virus. Phylogenetic analysis revealed that the virus isolate shared nucleotide identities of 96-98â% with H3N2 IAVs that circulated in humans from 2000 to 2003. Antigenically, sera from experimentally inoculated animals cross-reacted mainly with non-contemporary human-origin H3N2 influenza viruses. In an experimental infection in a commercial swine breed, the virus was of low virulence but was transmitted efficiently to contact pigs and caused severe disease when an infected animal acquired a secondary bacterial infection. This is the first report of a wholly human H3N2 IAV associated with clinical disease in pigs in South America. These studies highlight the importance of two-way transmission of IAVs and SIVs between pigs and humans, and call for enhanced influenza surveillance in the pig population worldwide.
Assuntos
Vírus da Influenza A Subtipo H3N2/patogenicidade , Influenza Humana/transmissão , Influenza Humana/virologia , Infecções por Orthomyxoviridae/transmissão , Infecções por Orthomyxoviridae/veterinária , Animais , Argentina/epidemiologia , Surtos de Doenças , Humanos , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Influenza Humana/epidemiologia , Dados de Sequência Molecular , Infecções por Orthomyxoviridae/epidemiologia , Infecções por Orthomyxoviridae/virologia , Filogenia , Filogeografia , Suínos , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/transmissão , Doenças dos Suínos/virologia , Replicação ViralRESUMO
In June-July 2009, an outbreak of pandemic (H1N1) 2009 infection occurred on a pig farm in Argentina. Molecular analysis indicated that the virus was genetically related to the pandemic (H1N1) 2009 influenza virus strain. The outbreak presumably resulted from direct human-to-pig transmission.
Assuntos
Bronquiolite Viral/veterinária , Surtos de Doenças/veterinária , Vírus da Influenza A Subtipo H1N1 , Influenza Humana/transmissão , Infecções por Orthomyxoviridae/veterinária , Doenças dos Suínos/epidemiologia , Criação de Animais Domésticos , Animais , Argentina/epidemiologia , Bronquiolite Viral/epidemiologia , Bronquiolite Viral/patologia , Humanos , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Infecções por Orthomyxoviridae/epidemiologia , Infecções por Orthomyxoviridae/patologia , Sus scrofa , Doenças dos Suínos/patologia , Doenças dos Suínos/virologiaRESUMO
El objetivo del trabajo fue caracterizar mediante PCR 47 aislamientos de Escheríchia coli recuperados de 32 cerdos con diagnóstico clínico de diarrea posdestete (DPD) y de 3 cerdos con enfermedad de los edemas (ED). Sobre 44 aislamientos provenientes de cerdos con DPD, 42 (95,5 %) fueron caracterizados como E. coli enterotoxigénicos (ETEC) y 2 (4,5 %) como E. coli productores de toxina Shiga (STEC). Catorce aislamientos de ETEC (33,3 %) fueron positivos para los genes estl/estlI/fedA. El genotipo más complejo fue eltA/estll/east1/faeG/aidA. Los aislamientos provenientes de cerdos con ED se clasificaron como STEC porcinos y fueron portadores de stxJaidA. Once aislamientos (25 %) fueron portadores del gen que codifica la expresión de la adhesina AIDA-I. Sin embargo, en ningún aislamiento se detectaron los genes que codifican la expresión de las adhesinas F5, F6, F41, de intimina y de "Paa". La prevención de la DPD y de la ED podría realizarse mediante el desarrollo de vacunas que generen anticuerpos contra las adhesinas de las cepas de E. coli prevalentes en la Argentina.
The purpose of this work was to characterize 47 Escherichia coli strains isolated from 32 pigs diagnosed with postweaning diarrhea and tree pigs with edema disease by PCR. Forty two (95.5 %) of the strains isolated from diarrheic pigs were characterized as enterotoxigenic E. coli (ETEC) and 2 (4.5 %) as Shiga toxin-producing E. coli (STEC). Fourteen (33.3 %) ETEC strains were positive for est/estll/fedA genes. The most complex genotype was eltA/estl/faeG/aidA. Strains isolated from pigs with ED were classified as porcine STEC and were stxjaidA carriers. Eleven (25 %) strains carried the gene encoding adhesln protein AIDA-I. However, genes coding for F5, F6, F41, intimin and Paa were not detected. The development of vaccines generating antibodies against prevalent E. coli adhesins in Argentina could be useful for the prevention of PWD and ED.