ABSTRACT
Until August 2007, Australia was one of only three countries internationally recognised to be free of equine influenza (EI). This report documents the diagnosis of the first cases of EI in Australian horses and summarises the investigations that took place over the next 5 days. During that time, a multifocal outbreak was identified across eastern New South Wales and south-eastern Queensland. The use of an influenza type A pan-reactive real-time reverse transcription polymerase chain reaction allowed rapid confirmation of suspect cases of EI.
Subject(s)
Disease Outbreaks/veterinary , Horse Diseases/virology , Influenza A Virus, H3N8 Subtype/isolation & purification , Orthomyxoviridae Infections/veterinary , Animals , Antibodies, Viral/blood , Contact Tracing/veterinary , Hemagglutination Inhibition Tests/veterinary , Horse Diseases/diagnosis , Horse Diseases/epidemiology , Horses , Influenza A Virus, H3N8 Subtype/genetics , New South Wales/epidemiology , Orthomyxoviridae Infections/blood , Orthomyxoviridae Infections/epidemiology , Orthomyxoviridae Infections/virology , Queensland/epidemiology , RNA, Viral/chemistry , RNA, Viral/genetics , Reverse Transcriptase Polymerase Chain Reaction/veterinarySubject(s)
Amaranthaceae/toxicity , Animal Feed/toxicity , Cattle Diseases/epidemiology , Dermatitis, Photoallergic/veterinary , Disease Outbreaks/veterinary , Animal Husbandry , Animals , Cattle , Cattle Diseases/chemically induced , Dairying , Dermatitis, Photoallergic/epidemiology , Female , New South Wales/epidemiologyABSTRACT
In three New South Wales dairy cattle herds with endemic Johne's disease, prevalence rates by faecal culture were determined to be 12, 18 and 22%, respectively. Whole herd faecal culture was shown to detect markedly more infected cattle than whole herd testing by the EMAI absorbed ELISA, particularly in the two herds with greatest prevalence. In the three study herds, five methods for whole herd faecal culture were compared in each. These included two methods based on primary culture on Herrold's egg yolk medium with mycobactin J (HEYM): (1) conventional decontamination with sedimentation and primary culture on HEYM; (2) Whitlock decontamination and culture on HEYM. The remaining three methods were based on radiometric (BACTEC) culture: (3) decontamination and filtration to BACTEC medium; (4) modified Whitlock decontamination to BACTEC medium and (5) Whitlock decontamination to BACTEC medium. For BACTEC cultures, two methods were compared as confirmatory tests for Mycobacterium paratuberculosis: mycobactin dependence on conventional subculture to HEYM and IS900 PCR analysis of radiometric media. Among 179 cattle tested simultaneously by all five culture methods, 38 cattle were confirmed to be shedding M. paratuberculosis. In identifying shedder cattle, method 5 was the most sensitive, followed by methods 2, 4, 1, and 3 was the least sensitive. The number of BACTEC cultures confirmed by mycobactin dependence or PCR was similar.
