RESUMO
Aujeszky's disease has been the subject of an eradication campaign in Denmark since 1980. A detailed knowledge of the virus strains present in the country was provided by restriction fragment analyses of older clinical isolates, and of isolates from all the virologically confirmed outbreaks since 1985. The introduction of foreign strains into southern border areas was demonstrated during the winters of 1984/85, 1986/87 and 1987/88. An epizootic during the winter of 1987/88 was shown to correlate with an unusual predominance of southerly winds. Both conventional and specific pathogen free herds became infected. A herd level case-control analysis of the outbreaks during the winter of 1987/88 revealed that there was a positive correlation between the risk of infection and the size of the herd. The observations support the hypothesis of airborne transmission of the disease.
Assuntos
Movimentos do Ar , Surtos de Doenças/veterinária , Pseudorraiva/transmissão , Animais , Estudos de Casos e Controles , Dinamarca/epidemiologia , Herpesvirus Suídeo 1/isolamento & purificação , Masculino , Polimorfismo de Fragmento de Restrição , Pseudorraiva/tratamento farmacológico , Pseudorraiva/epidemiologia , Especificidade da Espécie , Suínos , Doenças dos SuínosRESUMO
Six isolates of Suid herpesvirus 1 (SHV-1) collected from clinical outbreaks of Aujeszky's disease (AD) in Jutland in January-February, 1985, were compared by restriction fragment pattern (RFP) analyses with older SHV-1 isolates from Jutland as well as with SHV-1 isolates from different parts of West Germany and Ireland. The RFP analysis indicated that the outbreaks were caused by SHV-1 isolates introduced from abroad.
Assuntos
Herpesvirus Suídeo 1/classificação , Polimorfismo Genético , Polimorfismo de Fragmento de Restrição , Pseudorraiva/microbiologia , Doenças dos Suínos/microbiologia , Animais , Dinamarca , Métodos Epidemiológicos/veterinária , Europa Oriental , Alemanha Ocidental , Herpesvirus Suídeo 1/genética , Irlanda do Norte , Pseudorraiva/transmissão , Suínos , Doenças dos Suínos/transmissãoRESUMO
Purified DNA from 42 isolates of Suid herpesvirus 1 (SHV-1) collected during 1985 from clinical outbreaks of Aujezsky's disease on Danish farms was compared by restriction fragment pattern (RFP) analysis. The BamHI generated RFPs were found to be distinguishable, thus confirming RFP analysis as a potential epidemiological tool. However, because of variations within labile genome regions of epidemiologically closely related isolates, it was concluded that comparisons of RFPs should be interpreted with great care and only on the basis of a comprehensive reference material. With this proviso, the changes in RFPs occurring during the spread of the infection might be useful markers in the evaluation of epidemiological relationships. A simple procedure for obtaining satisfactory amounts of purified SHV-1 DNA is described.