RESUMO
Comparative analysis by RNA oligonucleotide fingerprints of total genomic RNA as well as the individual RNA segments of equine 2 influenza A virus strains from 1963, 1968, 1979, 1984, 1987 and 1988 revealed genetic diversity. Strains from the epizootic outbreak during 1978-1979 showed minor differences among their genomes. The Swedish isolates from 1979 up to 1988 showed increasing genomic heterogeneity indicating genetic drift.
Assuntos
Frequência do Gene , Vírus da Influenza A Subtipo H3N8 , Vírus da Influenza A/genética , Oligonucleotídeos/análise , RNA Viral/análise , Animais , Anticorpos Antivirais/análise , Reações Cruzadas , Testes de Inibição da Hemaglutinação , Vírus da Influenza A/imunologia , Mapeamento de Nucleotídeos , Homologia de Sequência do Ácido NucleicoRESUMO
The influenza virus has a genome consisting of eight RNA segments. A simplified technique to study the RNA segmental pattern by silver staining after gel electrophoresis has been developed. In addition, individual RNA segments could be isolated by a combination of polyacrylamide gel electrophoresis and isotachophoresis.
Assuntos
Orthomyxoviridae/genética , RNA Viral/isolamento & purificação , Eletroforese em Gel de Poliacrilamida/métodos , Variação Genética , Prata , Coloração e RotulagemRESUMO
The genome of the swine influenza H1N1 virus Sweden/83 was compared to other H1N1 viruses by oligonucleotide fingerprinting. This analysis revealed that Sweden/83 is identical to the Danish strain Sjaelland/82 and is thus to be placed in the group of "US viruses". On the other hand, the Danish strain Als/82 was found to be different, i.e., related to the Belgium/79 strain which is a representative of the "European viruses". The results of the present genomic analysis confirm the previous findings of relationships between the above strains.
Assuntos
Vírus da Influenza A Subtipo H1N1 , Vírus da Influenza A/genética , Oligonucleotídeos/análise , RNA Viral/análise , Animais , Eletroforese em Gel Bidimensional , Vírus da Influenza A/classificação , Mapeamento de NucleotídeosRESUMO
Strains of an influenza H10N4 virus have been isolated during an outbreak of a respiratory disease in mink on the south-east coast of Sweden. This was the first example of a disease in mammals caused by the H10 subtype. We compared the A/mink/Sweden/84 strain with two recent avian H10N4 isolates, one from fowl and another from a mallard, both isolated in Great Britain in 1985 as well as the prototype A/chicken/Germany/N/49 (H10N7). The comparison was carried out by genomic analysis of the strains by oligonucleotide fingerprinting and in bioassays on mink. The oligonucleotide fingerprint analysis revealed a high degree of genomic homology of around 98% between the viruses from mink, mallard and fowl. Only the recent avian isolates, that from the mallard and fowl could infect mink by contact, causing similar pathological and clinical signs and inducing seroconversion as did the mink virus. However, the susceptibility of mink to the fowl and mallard viruses by contact was less pronounced than that to the mink virus. Both the genomic homology and the similarities from the infectivity and pathogenicity studies between the mink virus and the recent avian isolates point to a direct invasion of the mink population by an avian H10N4 virus.