Source: Department of Agriculture and Water Resources
Lumpy Skin Disease (LSD) update
In the previous issue we reported the ongoing spread of lumpy skin disease (LSD) in Europe. In September 2017, the Food and Agriculture Organization of the United Nations (FAO) published a position paper advising governments across the Balkans and Eastern Europe to consider broader risk-based vaccination ahead of the 2018 high-risk season.
FAO calls for broader livestock vaccination to keep lumpy skin disease at bay in Eastern Europe and the Balkans
The FAO has also released a field manual on LSD for veterinarians, with useful images of clinical disease.
Would LSD be on your differential list for generalised skin disease in cattle? If not, see Lumpy skin disease: A field manual for veterinarians
Nairobi sheep disease virus/Ganjam virus
Nairobi sheep disease virus (NSDV), a tick-borne bunyavirus of the genus Nairovirus, is known to cause a highly pathogenic disease of sheep and goats in East and Central Africa. Serological evidence of NSDV has also been found in Mozambique and Botswana, and viral RNA was recently identified in ticks in China. A variant of the virus, known as Ganjam virus (GANV), is also found in parts of Asia, including India and Sri Lanka.
Nairobi sheep disease virus/Ganjam virus
These viruses cause acute haemorrhagic gastroenteritis in susceptible animals. Livestock bred in endemic areas may develop limited clinical disease, and large losses can occur when naïve animals are introduced or transported through infected areas. Ticks are important vectors for disease transmission and their survival, activity and spread can play an important role in disease dynamics. The tick Haemaphysalis longicornis, a known vector for NSDV, is present in southern coastal Queensland, coastal NSW and northeastern Victoria. NSDV/GANV has never been reported in Australia, and an uncontrolled outbreak would cause serious disruption to the sheep industry. While Australia doesn’t import livestock from NSDV/GANV endemic regions, tick vectors may inadvertently be imported on goods, pets or people. The increasing range of tick vectors, the presence of suitable tick vectors in Australia and the identification of NSDV/GANV in new regions suggests this virus may present a greater risk than previously thought.
Would NSDV/GANV be on your differential list for acute haemorrhagic gastroenteritis in small ruminants? If not, see Nairobi Sheep Disease
Mycoplasma species cause severe disease in cattle worldwide, most commonly associated with mastitis, arthritis, pneumonia and otitis media. The most frequently isolated species in cattle, Mycoplasma bovis, was first detected in Australia in 1970 and an increase in the incidence of disease in dairy herds has been observed since 2006. Culling remains the most common form of disease control due to the highly contagious nature and poor response of Mycoplasma bovis to antimicrobial treatment. In July 2017, the first outbreak of Mycoplasma bovis was reported in New Zealand, in several dairy herds in the South Island.
Australia supported the outbreak response in New Zealand through the International Animal Health Emergency Reserve (IAHER) arrangement, which facilitates the sharing of human resources during an emergency animal disease event. The IAHER is a formal arrangement between Australian and partner veterinary authorities in New Zealand, Canada, Ireland, the UK and the USA.
International arrangements for emergency animal disease outbreaks
Rabies in the region
Australia remains free of rabies, and strict conditions apply to the importation of dogs and other live animals. However, rabies is endemic in many countries in the region. In July 2017, Malaysia reported the first detection of rabies in dogs in almost two years, with over 40 cases confirmed in Sarawak and Perak states. As of September 2017, 6 human cases have been reported, marking the first rabies fatalities in Malaysia in almost 20 years. The affected states share borders with Thailand and Indonesia, where rabies is endemic.
Australia’s close neighbour Papua New Guinea (PNG) remains free of rabies, but shares a land border with Indonesia. A recent study assessed potential rabies entry routes into PNG and identified the highest risk pathways for introduction. Findings will support development of targeted measures to maintain PNG’s rabies-free status and better manage the risk of regional spread.
Risk assessment of the entry of caninee-rabies into Papua New Guinea via sea and land routes
Atypical Porcine Pestiviruses (APPVs)
A recent publication describes a novel pestivirus detected in a commercial piggery in Austria in 2015. The virus has been provisionally named ‘lateral-shaking inducing neurodegenerative agent’, or Linda virus, and is associated with CNS hypomyelination and congenital tremor (CT) in piglets. Historically classical swine fever (CSF), which is exotic to Australia, was the only pestivirus known to cause CT in piglets. Findings of the study indicate a cross-reactivity between Linda virus and other related pestiviral proteins, raising concerns regarding testing interference and implications for CSF surveillance.
Novel Pestvirus Species in Pigs, Austria, 2015
Linda virus has been added to the expanding group of atypical porcine pestiviruses (APPVs), which includes isolates from Australia, North America and Europe. The first APPV, known as Bungowannah virus, was characterised from an outbreak of stillbirths and sudden deaths in young pigs in 2003 in New South Wales, Australia. Bungowannah virus has not been detected since.
Bungowannah virus – a probable new species of pestivirus – what have we found in the last 10 years?
Emerging bunyavirus in East Asia
Severe fever with thrombocytopenia syndrome virus (SFTSV) is an emerging tick-borne Phlebovirus in the same family as Rift Valley fever virus. Since 2010, human cases of SFTS have been reported in China, the Republic of Korea and Japan, with case fatality rates reaching 47%. Media surrounding a case from Japan reports suspected infection of a woman following a cat bite, suggesting the first zoonotic transmission of SFTSV. The tick vector Haemaphysalis longicornis is present in Australia but SFTSV has not been reported.
Wohlfahrtiimonas chitiniclastica, a gram-negative aerobic bacteria, is a rare but emerging pathogen associated with myiasis in humans, livestock and wildlife. Since 2006, at least 13 human cases of infection with W. chitiniclastica have been documented worldwide across Europe, Asia and the Americas. Infections in white-tailed deer (USA), cattle (China) and a short-beaked common dolphin (Spain) have also been documented. The bacteria was first isolated in 2008 from the parasitic fly Wohlfahrtia magnifica, which is not known to be present in Australia. However, other species common to Australia, such as Lucilia sericata, Chrysomya megacephala and Musca domestica, have been identified as likely mechanical vectors.
In May 2017, the first human case of W. chitiniclastica was confirmed in Australia. Testing of archived samples has since confirmed W. chitiniclastica as an incidental finding in cattle (2015) and sheep (2017). However, disease associated with W. chitiniclastica infection in Australian wild and domestic animal species has not been reported. Considering the public health implications, W. chitiniclastica infection should be considered in human and animal cases of myiasis with associated systemic disease.
BSE modelling study in EU member states
A modelling study of bovine spongiform encephalopathy (BSE) cases in the EU found a constant rate of decline in new cases among member states following the implementation of reinforced feeding bans. While the prevalence of BSE is declining with each birth cohort, modelling results suggest the UK may experience sporadic cases until 2026.
Is there a decline in bovine spongiform encephalopathy cases born after reinforced feed bans? A modelling study in EU member states
Artificial intelligence for dairy herds
Researchers at Osaka University have developed an early detection method for lameness in dairy cattle using artificial intelligence. The method relies on machine learning to analyse images of cow gait, with a high reported diagnostic accuracy.
Image analysis and artificial intelligence will change dairy farming
Global AI update
The World Organisation for Animal Health (OIE) annual situational report for avian influenza is available online.
H5N6 HPAI (Philippines)
In August 2017, the Philippine Department of Agriculture confirmed an outbreak of H5N6 highly pathogenic avian influenza (HPAI) in poultry, marking the first detection of HPAI reported by the Philippines.
Highly pathogenic avian influenza, Philippines
H5N8 and H5N6 HPAI evolution
A publication in the Journal of Veterinary Science provides a useful and easy to read review of the evolution, global spread, and pathogenicity of H5 clade 126.96.36.199 HPAI viruses (H5N8 and H5N6 HPAI).
Evolution, global spread, and pathogenicity of highly pathogenic avian influenza H5Nx clade 188.8.131.52
H7N9 HPAI (China)
A report released by the World Health Organization (WHO) found that, between 2013 and 2017, exposure to live poultry or live bird markets was reported in 90% of human cases of H7N9 HPAI.
You may be looking at the first case and you do not want to become famous as the vet who missed it!
Call the EAD Watch Hotline number 1800 675 888 or contact your local government vet. You are not alone.