In the last edition of VetWatch I relayed the scope and challenges we were managing under COVID lockdown conditions during Australia’s biggest avian influenza outbreak. I am very pleased to be able to tell you now, that after more than six months of focussed effort, on 26 February 2021, Australia regained official freedom from high pathogenic avian influenza in accordance with international guidelines published by the World Organisation for Animal Health (OIE).
Throughout the outbreak, from the initial disease investigation and diagnosis, through the massive surveillance effort that was required, and in providing expert technical and industry knowledge, private veterinarians provided critical technical support to the Agriculture Victoria teams working across the State. Thank you all, on behalf of Agriculture Victoria and the poultry industry, for that assistance.
With the completion of one set of tasks comes a reminder that the risk of an incursion of an exotic animal disease is ever present. The detection of African swine fever and foot-and-mouth disease virus fragments in pork products seized at the Australian border early this year, highlights how easily these diseases could enter Victoria. We have also as I write just confirmed earlier this week Abalone Viral Ganglioneuritis (AVG) in wild abalone in an area near Cape Nelson.
To assist you in your day-to-day practice case work and to build your skills as the likely “first responder” for suspect emergency animal diseases you may encounter as you go about your work , Agriculture Victoria has developed e-learning materials on anthrax diagnosis and is once again offering our popular two-day course in animal disease investigations for private veterinary practitioners. I commend both offerings to you.
Over the next few editions of VetWatch I look forward to sharing with you some of the important work that my team are involved with including initiatives around antimicrobial resistance, advances in traceability, new on-line tools for practitioners involved in surveillance programs and areas of activity in developing necessary preparedness.
In the meantime, a reminder – Useful information that is specifically tailored for Victorian veterinary practitioners is available at VetSource. A version of this edition is also published on the Agriculture Victoria website.
Finally, thank you for your on-going contribution and assisting Agriculture Victoria in protecting Victoria’s agricultural industries. Thank you also to the many parts of the Agriculture Victoria and the CVO Office team who have helped contribute to this edition.
This is also of course an opportunity to thank the many people who have welcomed me to the role virtually, and I am looking forward to in more normal times meeting and working with you, and I hope you enjoy this edition of VetWatch.
Graeme Cooke
Chief Veterinary Officer (CVO)
Victorian Animal Health Surveillance - 1 December to 28 February 2021
compiled by Karen Moore
Victorian animal health data are collected from a number of sources, including targeted surveillance activities, monitoring programs, disease control programs, diagnostic laboratories, livestock producers and field investigations conducted by Agriculture Victoria (AgVic) staff and private veterinary practitioners.
There were 366 disease events in livestock investigated in Victoria between 1 December 2020 and 28 February 2021 . The geographic spread of the investigations (Figure 1) and the most frequently reported diseases in each species are shown below.
(* Based on disease investigations reported to Agriculture Victoria. Data does not include wildlife or companion animals.)
Figure 1 Location of field investigations, by species between 1 December 2020 and 28 February 2021.
Cattle
There were 139 disease investigations of cattle between 1 December 2020 and 28 February 2021.
Table 1 shows the most frequently observed cattle diseases in each region during the period. It does not include 56 investigations where no definitive diagnosis was made or cases with results pending. Cases of clinical disease where no definitive disease agent was identified were reviewed in the context of the surrounding circumstances, and exotic or emergency diseases were excluded where appropriate.
Salmonellosis continues to be the most commonly diagnosed disease of cattle.
Table 1: Most commonly diagnosed diseases of cattle - 1 December 2020 to 28 February 2021
Disease
NORTHERN
SOUTH EAST
SOUTH WEST
Salmonellosis (general)
9
5
3
Bovine viral diarrhoea/pestivirus (not type 2)
2
7
2
Internal parasites-helminths
1
6
1
Rotavirus
4
2
2
Cryptosporidiosis
3
2
1
Campylobacter infection (not notifiable species)
2
2
0
Sheep
There were 103 disease investigations in sheep reported to AgVic between 1 December 2020 and 28 February 2021.
Table 2 shows the most frequently observed sheep diseases during the period. It does not include 31 investigations where no definitive diagnosis was made or cases with results pending. Cases of clinical disease where no definitive disease agent was identified were reviewed in the context of the surrounding circumstances, and exotic or emergency diseases were excluded where appropriate.
Table 2: Most commonly diagnosed diseases of sheep - 1 December 2020 to 28 February 2021
Disease
NORTHERN
SOUTH EAST
SOUTH WEST
Internal parasites-helminths
16
2
9
Paratuberculosis (Johne's disease)
5
0
4
Mycoplasma infection (not notifiable species)
7
0
1
Internal parasites-protozoa
2
1
1
Pasteurella infection (not notifiable species)
1
0
2
Salmonellosis (general)
2
0
1
Goats
There were 15 disease investigations in goats reported to AgVic between 1 December 2020 and 28 February 2021.
Table 3 shows the diseases observed in goats during the period. It does not include eight investigations where no definitive diagnosis was made.
Table 3: Diagnosed diseases of goats - 1 December 2020 to 28 February 2021
Disease
NORTHERN
SOUTH EAST
SOUTH WEST
Internal parasites - helminths
2
1
1
Caprine arthritis encephalitis
0
1
0
Campylobacter infection (not notifiable species)
0
0
1
E.coli(not verocytotoxigenic)
1
0
0
Horses
There were 28 disease investigations of horses reported to AgVic between 1 December 2020 and 28 February 2021. No definitive diagnosis was found in sixteen investigations and there are three pending final results.
Seventeen investigations were undertaken to exclude Ross River Virus. Samples from two of these horses were submitted for Hendra exclusion testing to the Australian Centre for Disease Preparedness (ACDP). Both were Hendra negative. West Nile fever and Equine encephalomyelitis (EEV) were excluded as the cause of disease in one of the neurological investigations. Table 4 shows the most frequently observed diseases during the period for each region. It does not show investigations where no definitive diagnosis was made.
Table 4: Diagnosed diseases of horses and donkeys - 1 December 2020 to 28 February 2021
Disease
NORTHERN
SOUTH EAST
SOUTH WEST
Salmonellosis
4
0
0
Ross River virus
2
0
1
Strangles
0
1
0
Suspect neonatal isoerythrolysis
0
0
1
Poultry
There were sixty-four disease notifications or investigations of poultry reported to AgVic between 1 December 2020 and 28 February 2021. The investigations involved 54 chicken flocks, 3 duck, 4 turkey, 2 emu and a mixed poultry flock.
The most common diseases diagnosed are listed in Table 5. The table does not include thirty-four cases where no definitive disease agent was found. No definitive disease agent was identified in any of the four turkey investigations. Cases of clinical disease where no definitive disease agent was identified were reviewed in the context of the surrounding circumstances, and exotic or emergency diseases were excluded where appropriate.
Table 5: Most commonly diagnosed diseases of poultry - 1 December 2020 to 28 Febraury 2021
Species
Disease
NORTHERN
SOUTH EAST
SOUTH WEST
Chickens
Infectious laryngotracheitis
2
1
7
Infectious coryza/infectious laryngotracheitis
1
2
4
Intestinal parasite - protozoa
0
0
2
Marek’s disease
1
0
1
Other bacterial infection
1
0
2
Emus
Toxicity
1
0
0
Salmonellosis (general)
1
0
0
Mycotic/fungal infection
1
0
0
Ducks
Toxicity
1
0
0
Pigeons
There was one disease investigation of pigeons reported to AgVic between 1 December 2020 and 28 February 2021. Pigeon paramyxovirus Type 1 was confirmed as the cause of disease.
Pigs
There were 14 investigations reported to AgVic between 1 December 2020 and 28 February 2021.
Exotic disease exclusion testing undertaken at ACDP in the period included African Swine Fever, Classical Swine Fever, Transmissible gastroenteritis and Porcine epidemic diarrhoea virus.
Table 6 includes a list of the diseases diagnosed during the period (note: multiple diseases were diagnosed for some investigations). The table does not include four cases where no definitive diagnosis was made and one case with results pending.
Table 6: Most commonly diagnosed diseases of pigs - 1 December 2020 to 28 February 2021
Early detection of an emergency animal disease threat is vital to preventing its spread. AgVic encourages and facilitates the reporting and investigation of suspect EADs.
There were 132 investigations to exclude suspect emergency or exotic diseases undertaken between 1 December 2020 and 28 February 2021 – see Table 8 below. Note that some investigations exclude more than one EAD (e.g. animals tested for foot-and-mouth disease will generally also be tested for vesicular stomatitis).
The data includes clinical disease investigations by private and AgVic veterinarians as well as animals tested as part of on-going AgVic surveillance projects at abattoirs, saleyards and knackeries. The data includes livestock, companion animals and wildlife. Figure 2 shows the location of investigations.
Table 7: EAD exclusion testing undertaken between 1 December 2020 and 28 February 2021
Disease
Investigated
Confirmed
African swine fever
1
0
Anthrax
21
0
Australian lyssaviruses including bat lyssavirus
13
0
Avian influenza
64
0
Bluetongue
1
0
Brucellosis - bovine (B. abortus)
11
0
Brucella canis*
2
o
Brucella suis*
2
0
Classical swine fever
1
0
Equine encephalomyelitis (East/West/Venezuelan)
1
0
Foot and mouth disease
1
0
Hendra virus
2
0
Lumpy skin disease
2
0
Newcastle disease
16
0
Porcine Epidemic Diarrhoea Virus
1
0
Post weaning multisystemic wasting syndrome
1
0
Transmissible gastroenteritis
1
0
TSEs (BSE, scrapie, CWD, FSE)
15
0
Vesicular stomatitis
1
0
West Nile fever (clinical infection)
1
0
* Exclusion testing in dogs
Figure 2. Location of suspect EAD investigations by species (1 December 2020 to 28 Febraury 2021). Wild bird surveillance is not included.
Introducing New Staff Members
Hayden Morrow
Hayden started in September last year as Veterinary officer, at Epsom.
Hayden graduated from Charles Sturt University in Wagga Wagga with a strong interest in livestock production. He started his career as a dairy/mixed veterinarian at Cobden in South West Victoria. In 2020 Hayden changed roles to become the District Veterinary Officer at Colac for 6 months before relocating to his current role as a Veterinary Officer for the Bendigo district. Hayden has found a particular interest in emergency response, product integrity and disease surveillance whilst working within the department.
Chris Stott
Chris has taken up the role of Veterinary officer, at Seymour.
Bathurst, Berry, Britain and beyond. Chris Stott has worked in mixed animal vet practices around the world before starting with us at Seymour. Chris was working on export boats between Fremantle and the Middle East when he saw the opportunity to jump ship.
Chris brings with him wide-ranging experiences with both large and small animals, from working in a veterinary clinic with a focus on dairy to more general practice. He admits that the opportunity to participate in emergency animal disease responses were a large drawcard to this veterinary officer role.
In general, the role involves working with private veterinarians, answering questions about animal diseases and approving disease investigations, plus responding to, and managing animal welfare complaints.
When Chris and his partner aren’t out exploring with their two Border Collies, they hope to be enjoying the extensive outdoor pursuits Victoria has on offer, with the ski slopes and high-country trails high on their agenda.
National freedom from Highly Pathogenic Avian Influenza
by Dianne Phillips (Senior Veterinary Officer)
In 2020, Victoria endured the largest ever outbreak of avian influenza on record in Australia. The outbreak involved seven properties in three regions across the state which tested positive between 31 July 2020 and 25 August 2020. Overall, three species of commercial birds were affected, and three different strains of the virus were diagnosed.
As of 26 February 2021, Australia regained freedom from high pathogenic avian influenza in accordance with international guidelines published by the World Organisation for Animal Health (OIE). This has required almost 1,400 surveillance visits and 2,700 surveillance text messages. AgriBio, Agriculture Victoria’s research and diagnostics laboratory, analysed 21,650 samples since the response began on 31 July 2020.
Throughout the surveillance effort, private vets provided critical technical support to field surveillance teams working across the Golden Plains Shire and in the Bairnsdale and Kerang areas.
As surveillance has found no further detections of avian influenza, as of 9 March 2021 Control Areas near Bairnsdale, Kerang and Lethbridge have been lifted. Permits are no longer required for the movement of poultry, poultry products and vehicles involved in poultry production in these areas.
Maintaining freedom from highly pathogenic avian influenza
Migratory birds can pose a risk if they harbour avian influenza virus and then transmit this infection to waterfowl that are nomadic within Australia. These nomadic birds can then mingle with and spread the infection to domestic birds such as poultry. It is not unusual for avian influenza virus to be detected in wild birds in Australia. Wild birds can carry the virus without showing any signs of infection.
Regardless of whether your clients are commercial producers or just keep a few chickens in their backyard, there are several biosecurity practices they can put in place to protect their birds from disease:
Restrict contact between kept birds and wild birds. Contact with wild birds can be minimised by making the free-range environment less attractive to them, for example, place feeders and water sources inside sheds, rather than in the open where wild birds will have easier access. Using fencing or netting for free-ranging birds, are other options.
Keep poultry sheds, yards and aviaries clean, including equipment. Clean thoroughly with a detergent before applying a disinfectant.
Quarantine new birds before introducing them to the resident flock.
Limit visitors to your birds. Check if essential visitors have recently visited other premises where poultry is kept.
If attending bird shows, always practice good hygiene.
Always wash hands before and after handling birds and eggs.
Poultry farmers should change into clean footwear before entering poultry houses or hen facilities, to stop the potential transfer of disease from outside.
Veterinarians investigating suspected cases of avian influenza MUST IMMEDIATELY notify Agriculture Victoria by calling the all-hours Emergency Animal Disease Watch Hotline on 1800 675 888. Agriculture Victoria will advise on samples required, sample transport requirements and any additional activities required.
Recent detections of Ross River virus in Victorian horses
by Dr Josie Holmes (Principal Veterinary Officer – Equine)
Following temperatures and rainfall favourable for mosquito breeding, there have been surges in detections of Ross River virus (RRV) in mosquitoes, horses and people this year.
Veterinary practitioners are consequently reminded to consider infection with arboviruses, including Murray Valley encephalitis virus, RRV and Kunjin virus, as differential diagnoses when examining any horse displaying unexplained muscular or neurological signs (depression, changes in temperament, incoordination, etc) particularly in cases suggestive of viral encephalitis.
Paired serum samples (taken two weeks apart) will facilitate diagnosis.
RRV is the most common and widespread arbovirus in Australia. Major outbreaks have occurred in all parts of Australia, primarily from January to May each year. RRV disease is considered endemic throughout most parts of Victoria, particularly around inland waterways and coastal regions, but not in metropolitan Melbourne. Epidemics usually follow heavy rains, or high tides that inundate salt marshes or coastal wetlands. RRV disease is not a notifiable disease in horses in Victoria.
It is advisable for horse owners to reduce breeding sites for mosquitoes by emptying accumulated or stagnant water from items such as old buckets, tubs and tyres. Additional protection can be provided through the use of suitable repellents or protective coverings like summer rugs or fly veils.
Please note that a differential diagnosis of Hendra virus infection should always be considered when examining a horse with neurological signs. It is very important that an accurate diagnosis/disease exclusion is obtained, and that suitable personal protective equipment is always worn when handling and sampling horses displaying neurological signs.
Horse owners and veterinarians are reminded to remain vigilant for diseases such as Hendra and should report any unusual illness or suspicion of disease to the Emergency Animal Disease Watch Hotline on 1800 675 888.
by Dr Shyuan Seah (Principal Veterinary Officer – Animal Health and Welfare Policy)
Following the detections of ehrlichiosis in New South Wales and Queensland, and within the vector (thebrown dog tick; Rhipicephalus sanguineus) in South Australia, Victorian veterinarians are urged to keep a lookout for dogs showing symptoms of the disease and also to retain any ticks found on dogs for identification.
A biosecurity advisory with details of the disease was distributed in February 2021 through the Veterinary Practitioners Registration Board of Victoria. The Biosecurity Advisory and further information about ehrlichiosis are available on the Agriculture Victoria website.
Canine monocytic ehrlichiosis, or infection with Ehrlichia canis, is a notifiable disease in Victoria. Veterinarians and other persons suspecting the disease must report it immediately to the all-hours Emergency Animal Disease Hotline on 1800 675 888. You can discuss a suspect case with the duty officer and receive further instructions regarding submission of canine blood and/or tick samples. There is no cost to submit samples for testing for E. canis or for the identification of ticks.
Please collect at least two blood samples (one plain tube and one EDTA) preferably prior to administering any antimicrobial treatment and freeze any ticks (including those found by owners) in a sealed bag or sample container. Send samples to the state laboratory, AgriBio.
Infectious laryngotracheitis in Victorian broilers
by Dr Yonatan Segal (Principal Veterinary Officer – Poultry and Emergency Diseases)
In early 2021, two incidents of Infectious laryngotracheitis (ILT) in commercial broilers followed a quiet period of approximately 18 months without any outbreaks in Victoria. In both cases, a class 9 virus was identified even though these outbreaks occurred geographically far apart, the first case occurring near Pakenham while the second case was located north of Bendigo.
ILT is an acute, highly contagious, herpesvirus infection of chickens, characterized by obstruction of the trachea or larynx with plugs of mucus and blood. The birds present with severe dyspnea, cough with moist rales and often extend the neck to breathe. ILT can cause high mortality and severe production losses.
The latest case affected a flock of 250,000 45-day-old broilers in a large complex of 1.2 million birds. The flock was not vaccinated for ILT. A sudden onset of high mortality and severe respiratory symptoms raised the alarm. Tracheal swabs were sent by the servicing veterinarian to the state laboratory (AgriBio). The PCR test results confirmed the suspected ILT infection and excluded Avian influenza.
Anthrax eLearning – make sure you’re prepared
The early detection of diseases such as anthrax play an important role in protecting the health and welfare of Victorian livestock to support our important agricultural industries.
Agriculture Victoria has released a new series of online learning modules to help veterinarians better understand, prevent and respond to suspected cases of anthrax.
Anthrax is an infectious bacterial disease that can infect people and a wide range of animals. Cattle and sheep with anthrax usually die suddenly. Anthrax is known to occur intermittently in grazing livestock and there have been sporadic cases in Victoria, most recently in northern Victoria.
The training modules provide guidance on recognising suspected cases of anthrax, how to test and respond to disease and the use of protective anthrax vaccination.
Any suspect cases of anthrax must be reported immediately to the Emergency Animal Disease Watch Hotline on 1800 675 888. Further information is available at www.agriculture.vic.gov.au.
Animal Disease Investigation (ADI) course
Agriculture Victoria is running courses in animal disease investigation for private veterinary practitioners in May 2021 and again in March and April 2022.
N.B. All the courses for this year (2021) are fully booked out.
The course will be available again in late March / early April 2022 and will continue enabling participants to investigate animal disease events confidently and competently through a combination of theory and practice. The theory sessions are highly interactive involving animal disease case studies, set tasks and short presentations; the practical sessions focus on the conduct of a safe, systematic, comprehensive ruminant necropsy.
This course is designed for veterinary practitioners who work with livestock, even infrequently, in both rural and peri-urban areas of Victoria. It is supported by the cattle, sheep, goat and swine industries of Victoria.
Course content
Day One topics include:
How to prepare for a successful investigation, using Agriculture Victoria’s resources to help you.
How not to miss anything (including the diagnosis) and avoid common mistakes
How to manage your time and energy, and still get the detailed history you need
Conceptual frameworks that make the most complex disease events easy to solve i.e. practical field epidemiology
Tips and tools that can make the difference between success and failure
How to describe, interpret and photograph necropsy findings.
Day Two topics include:
How to prevent a zoonotic infection
How to avoid spreading disease around the locality
How to store, transport and set-up your equipment
How to open a carcass
How to collect high quality, uncontaminated samples and take useful photos
Common mistakes when performing necropsies and how to avoid them
Getting samples to the laboratory safely, legally and in good condition
How to sharpen a knife.
Course structure and duration
This is an intensive, two-day training course that will be delivered four times during 2022 in Bendigo.
Day 1 of the course runs from 8.30 am to 5.00 pm, followed by an evening session from 7.00 pm to 9.00 pm. Day 2 of the course runs from 8.30 am to 4.30 pm.
Your Agriculture Victoria tutors for the course will be a pathologist from AgriBio (Agriculture Victoria’s animal diagnostic laboratory) and experienced field veterinarians.
Course costs
Training costs, accommodation and all meals (excluding alcohol) associated with course delivery will be met by Agriculture Victoria. Participants will need to make their own transport arrangements to / from Bendigo.
Qualification pathways
Participants who successfully complete the course will be awarded a certificate of completion and will be eligible to claim 15 structured activity CPD units.
How to apply
Please note that all courses are full for this year.
Expressions of Interest for 2022 courses can be made by email your details and interest togill.holland@agriculture.vic.gov.au.
You will be contacted by Ms Holland when the course is set up next year to gauge your interest and send out an application form.
Veterinary Practitioner Consultative Group (Victoria)
Recognising the significant contribution made by Victorian veterinary practitioners to animal health and biosecurity, Agriculture Victoria’s Chief Veterinary Officer, Dr Graeme Cooke, is seeking to enhance consultation between Agriculture Victoria, private veterinary practitioners and other relevant stakeholders.
The proposed Veterinary Practitioner Consultative Group (VPCG) is a non-statutory forum with the primary objective of two-way engagement between the Victorian veterinary profession and Agriculture Victoria. It is envisaged that discussions about disease surveillance activities will initially contribute significantly to meetings. However, the intended scope of meetings is to broaden to all aspects of animal health and biosecurity.
The Chief Veterinary Officer’s team is currently seeking expressions of interest for representation on the group from veterinarians with experience with:
cattle
small ruminants
horses
pigs
poultry
companion animals, and/or
native wildlife
It is expected that the committee will meet quarterly. Meetings will generally be held via web-based video conferencing, although face-to-face meetings may occasionally be required.
Each member will cover their own expenses incurred by participation in meetings.
If you feel you would like to contribute in this group, please forward a few paragraphs about yourself and how you could contribute to alison.lee@agriculture.vic.gov.au.
The closing date for this process will be Friday 4th June, 2021.
Any queries or to obtain a copy of the Terms of Reference for the committee, please contact Alison at the above email address or on 0418 176 428.
Thank you.
