So this next part we're going to be talking about what we call the five priority EAD's. Federal and state governments have come together and identified the five diseases that based on risk assessment will have the largest consequence for the Australian economy as a whole and the highest likelihood of an incursion within the next few years.
But firstly, we call it EAD's. I've worked in government now for two and a half years and I realize that you need a little book with all the acronyms in it and EAD's is one of those so EAD emergency animal diseases.
So what is an emergency animal disease? It's a disease that's considered by the Australian government and Industry as I said, to be of national significance due to serious or severe impacts on a number of factors.
It's likely to have significant effects on Animal Health and potentially resulting in livestock deaths, production loss and in some cases human health and the environment. They have an impact on our ability to trade and negatively impact the economy which I think you'll soon find particularly if we have foot and mouth disease that's a - it's a quite a big understatement. Also animal health issues, animal welfare issues.
I think we get so bogged down thinking about the economic impacts of these diseases; I know last week at our district back conference Peter Windsor who a lot of you would know, spoke about lumpy skin disease and the work done in Indonesia on that and it was just from a welfare perspective just devastating.
So we do have to look at the Animal Welfare implications of these diseases as well. An EAD may be a known disease, it may be a variant of an endemic disease or it may be a new disease to Australia.
National and state government plans exist for responsive management of EADs and these are Oz vet plans which I'm sure most of you are familiar with they're all available on the animal health Australia website as well as supporting documents, such as documents around decontamination and and other areas like that.
Makes it interesting reading if you've got a spare half an hour up your sleeve, the foot and mouth disease document in particular is very comprehensive very readable and I think you'll find it if you did have a look at it, you actually learn quite a lot about the disease itself I know I certainly did.
FMD is classified as a category 2 disease in terms of funding if an outbreak should happen. 80% of that funding will be supplied by government and 20% supplied by industry so all these diseases are put into different categories in terms of funding should a response be needed.
So how are these EAD's managed in New South Wales?
If you look at the biosecurityactT there's a schedule in it that lists all what we call prohibited matter and these emergency animal diseases are included as as prohibited matter and as Elise said all our district vets and biosecurity offices in Local Land Services are all authorized officers under the biosecurity act which gives us special powers if we suspect a property has animals with certain diseases that come under prohibited matter we can actually enter that property, take samples, request information from the owner under the biosecurity act.
So it gives us additional legal powers to respond if we suspect that something is amiss. There's that phone number again. If you don't know who your Local District Bet is, please come and see me during the break and I can tell you who they are and give you their phone number. Certainly we've got that 24-hour number as well so if you're stuck - mind you on a Saturday morning we've had private vets ringing our district vets and God love them they still answer their phones, so if you ring the district vet, ring the hotline and get in touch with us if you see anything suspicious and then that's your first port of call.
Under the biosecurity act there are a number of different clinical signs that we see that are declared biosecurity events and it is a legal responsibility for those events to be reported to us. So for obvious reasons, the appearance of ulcers or blisters on the mouth or feet of ruminants or pigs, the appearance of skin nodules on cattle - obviously for lumpy skin disease concerns, an unexplained or significant increase in a mortality or morbidity rate in plants or animals, unexplained and significant fall in production relating to plants or animals; so for example if you're preg-testing and there's low repro rates that you can't explain, then that would be a declared biosecurity event and something that really probably should be investigated, appearance of other unexplained or significant clinical signs in animals including but not limited to unexplained neurological signs or conditions and that's you know we're looking at horses as well so things like Hendra virus obviously we're concerned about and we are very good in this region. I've noticed a lot of the horse vets will do Hendra exclusions on horses with either colic or neurological signs, so full credit to the horse vets out there for taking that on board.
You will hear a lot about sampling and lab testing today and you'll get a lot of practice in doing that in the practical sessions, which is something that you really should make the most of that opportunity. It's really important that sampling is conducted correctly, so the lab can obviously give you the best chance of an accurate diagnosis. There's those phone numbers again. If you've got samples that you suspect will need an EAD exclusion testing, please call EMAI or call that 1-800 number because we need to give the lab notice that these samples are coming in.
Also if a disease is zoonotic, they like for you to ring them and just let them know and to to make sure the samples are well and truly labeled potential zoonosis for obvious workplace health and safety reasons. If you need assistance, over the phone assistance or if you need any kind of materials for sampling that you know you might need media that you do not have, please call your District Vet because quite often we have media available that's on hand and we can get it to you, or you can come and pick it up from one of our offices that's a that's not a problem.
Our top five priority EAD's; interesting to note that Japanese Encephalitis is not on this list and it was a big surprise when it hit us last year. Two piggeries in our region were two of the first pigaries that were diagnosed with it and it was it was actually quite great work by the Pathologists at EMAI to diagnose it, because it was the last thing anyone suspected. So even though these are the priority EAD's there's lots of EAD's out there that we need to be aware of so if you're seeing anything that just doesn't make sense if you're doing testing that comes back negative for all the regular things please call the Pathologists at EMAI.
They are fantastic and they might suggest further tests for things that are less common, but we need to rule out.
So the top five priority EAD's are obviously foot and mouth disease - a big one that we're all worried about; lumpy skin disease; African swine fever; African horse sickness and highly pathogenic Avian Influenza.
So back in March 2021 the University of Melbourne did a risk analysis and found the risk of an incursion within the next five years of African swine fever; African horse sickness; foot and mouth disease disease and lumpy skin disease, and you can see those figures there and they suggested that there was a 42% probability of an incursion of one of these diseases in Australia in the next five years.
Highly pathogenic Avian influenza was not on there because the year before that was conducted Victoria had actually had a HPI outbreak which is obviously now resolved.
So that was in 2021, but going back to just over 12 months when foot and mouth disease and lumpy skin disease were both diagnosed in Indonesia, those risk analyses were were conducted again and obviously being geographically closer to Australia, the risk of those diseases coming into the country did increase.
So, lumpy skin disease went from 8% to a 28% risk of an incursion in the next five years.
Foot and mouth disease: so there was a lot of media attention around this happening in Indonesia and people demanding that you know, people coming back from Bali had to give up their footwear and things like that - the actual risk of foot and mouth disease coming into Australia didn't go up that much higher so it went from 9-12% and the reason that lumpy skin disease is obviously higher, is because it's vector-borne rather than coming on the back of contaminated meat products; which is the most likely way we're going to get a foot and mouth disease incursion.
The impacts of an incursion particularly with foot and mouth disease would be devastating. So we estimate 80 billion dollars over 10 years. That's based on export markets being shut down overnight and internal damage to the Australian economy as well, there will be obviously community impacts. Small communities, rural communities that depend on on farming will be obviously be adversely affected, social wellbeing, financial hardship. It will also hurt supporting systems and of course the Animal Welfare component as well.
Lumpy skin disease would cost about $8 billion in the first year and African swine fever would cost about $2 billion over five years.
So this is why it's so important that we're aware of these diseases and that we're alert to any clinical signs that we may see, to get them tested and excluded and the exclusion tests are just as important as the inclusion tests, so then we can continue to prove freedom of disease to our export Partners.
If you see anything suspicious, even if it's sort of low suspicion, then please do do an exclusion test just so we can add to that data.
Foot and mouth disease is obviously a very serious highly contagious viral disease affecting cloven-hoofed animals. There's seven serotypes and there's a lack of cross protection between serotypes. Incubation is variable depending on: the strain, the dose, the husbandry and animal variables such as immunology, as well as root of transmission.
Infected animals excrete virus - there's probably a better slide to look at - excrete the virus in the fluid from ruptured vesicles, exhaled air, saliva, milk, semen, faeces and urine.
The primary mode of transmission is by direct contact and fomites, or movement of animals, or wind-borne spread. It can remain viable in the environment for weeks or even longer, it's highly susceptible to both acid and alkaline disinfectants, which is why we stocked up on a lot of citric acid for our decontamination kits, because that change in PH really does inactivate the virus. It can survive in frozen, chilled and freeze-dried meat foods, including meat and dairy and this is obviously the biggest concern for Australia: imported products coming in.
Those products then being fed to pigs - pigs are an amplifier of the virus, and that's how they contract the virus. So a pig will shed about three times as many viral particles as an infected cow, and this is the most likely way that this disease will come into the country - through infected contaminated food products.
This is a map that is fairly recent - March this year, showing the spread of foot and mouth disease globally. Those countries that aren't coloured actually don't report, so they don't have an official status. It's probably best to assume that there is foot and mouth disease in those countries, rather to assume that it isn't. As you can see, Australia is currently FMD-free and a vaccination free status. So it is important that we maintain that vaccination-free status and that will play a part in how we respond to an incursion.
So obviously vaccines will be a part of a response should have been needed, but the sooner that we can be declared as free of the disease without vaccination, that will open up more export markets for us again.
So obviously the planning for a response and how we use vaccines in particular in that response will be will be crucial in terms of how we will come out of the response at the other end.
Whenever you see vesicles in cloven hoofed animals you should do an FMD exclusion, if you're not sure how to do that ring your District Vet, ring that 1-800 number and we can step you through what samples to collect and obviously today, our pathology team will take you through a bit more about what samples that they need.
A provisional diagnosis should be made if there's a combination of the following signs: acute lameness in a group of animals, lameness is actually particularly in sheep is something that needs to be reported to district vets for a variety of reasons: foot and mouth disease is one of them but also virulent foot rot being a regulated disease in New South Wales. Any signs of lameness please alert the district vet about it. Excess salivation, vesicles in the mouth on the feet or on the teats, fever and a drop in milk yield.
Morbidity of foot and mouth disease often reaches 100%. Mortality is quite low except in younger stock. As I said before, pigs are more susceptible to oral transmission than aerosols so they're more likely to get it through eating contaminated foods.
That's why swill feeding is illegal, for that reason and because of African swine fever. We regularly conduct swill feeding audits, particularly on people with one or two pigs in the backyard that might just throw them the um the food scraps and if it's got meat in the food scraps, particularly things like bacon or ham that might have come in from overseas, then that's considered swill feeding and it's something that we take very seriously.
That's why you might see a lot of media attention around swill feed and particularly if you follow us on things like Facebook.
Cattle are an indicator species, they're highly susceptible to aerosol infection and the clinical signs are very overt in cattle. In sheep, clinical signs aren't as overt as they are in in cattle, but it is some still something to be aware of. They're equally as susceptible to the virus but just don't show up those signs.
As you can imagine, going through those clinical signs, there's lots of differential diagnoses for foot and mouth disease. For example I know our district vet in Gundagai towards the end of last year, was called to a property up near Tumut where there were vesicles in a couple of steers up there. She did obviously a foot and mouth disease exclusion as you would, it turned out that they were persistently infected so it was mucosal disease. So, common things occur quite commonly as we know in the vet world, but if you do see something like that, please contact us and we can help you rule out FMD.
Lumpy skin disease. It's another disease that we've heard a lot about of over the last 12 months. Unlike foot and mouth disease, lumpy skin disease only affects cattle and buffalo. It's also a viral disease. The incubation periods around 4 to 14 days usually less than 28 days and it causes anything from severe systemic disease, with clinical signs - it could be an apparent disease to really mark disease, so - I'm pretty sure there's some pictures coming up - it's a horrendous disease to see and the effects it has on the animals; it makes them incredibly unwell.
It's a vector-borne virus that's spread primarily by biting insects, contaminated feed, water, vehicles and nitrogenic means can also spread the virus. This is where lumpy skin disease is from 2022 so I think it was March/February or March last year when it was first diagnosed in Indonesia. Obviously we're on high alert for that in the Northern parts of the country, given it's vector-borne. With the right wind directions then it is possible for that to to jump that small distance across into Northern Australia. But in saying that, every Monday morning at the Wagga Wagga Cattle Sales, we have an LLS staff member either one of our vets or our biosecurity officers going in inspecting all the cattle that go through the sales and that's being done state-wide through Local Land Services at the moment.
We haven't had to do any exclusions here, but I know in around Hunter, North Coast. they've had to do exclusions of cattle going through sale yards. It's often just from Buffalo fly or other biting insects, obviously no LSD cases yet but they have had to do exclusions on. So it is obviously something that we're doing active surveillance on.
Clinical signs of lumpy skin disease are fever, depression - these animals are highly unwell, nasal and ocular discharges, swelling of the limbs, lameness - reluctance to move and even eat. Enlarged, superficial lymph nodes, reduced milk production and skin lumps; and the skin lumps actually occurs late in the duration of the disease, so it's more the depression, the fever are the initial signs and then you start seeing these lumps develop.
Morbidity can be up to 45%. Mortality again is quite low, similar to foot and mouth disease, so one to five percent but from a welfare perspective it is a devastating disease. Just that presentation last week of Peter Windsor really highlighted to me how nasty this disease would be if it came into Australia.
Again, lots of differentials. We have one of our district vets up in the north of the state do a rule out of lumpy skin disease of a cow that was in a feedlot. Turned out the cow had cutaneous lymphoma, so that was an interesting one-off case but obviously lots of differentials can appear for lumpy skin disease as well.
African swine fever; that's a severe infectious haemorrhagic viral disease obviously affecting pigs. It has an incubation period of usually less than 20 days. It's spread by direct contact within herds and indirectly through ingestion of contaminated material there was an ASF outbreak in Timor Leste, not too long ago and that was discovered to be because there were products from contaminated products coming in from China that were dumped there. They were very cheap products so the local pig producers would take those and feed them to their pigs and ended up unfortunately with African swine fever in those pigs. So again, another reason why we like to do swill feeding audits.
Pigs recovered, they recover from either acute or chronic infections and they may become persistently infected acting as virus carriers. Ticks, can act as reservoirs and biological vectors and the virus can remain viable for very long periods. There's currently no vaccine or treatment for it.
This is a relatively recent/very recent map of the distribution of African swine fever. Very much a sort of African/Eurasian disease at the moment but it is one of those diseases that is getting closer and closer to Australia. That's why it's one of our top five diseases particularly around the impact that it will have to our pork industry.
These are some of the clinical signs; I'm not sure how many of you would - you'd probably see cattle and sheep more often than you'd see pigs, but you know, you can't rule out having to go off and see a pig if someone has one or two pigs that is displaying signs like this. The pigs might being the peracute form of the disease and just be found dead. The acute form as you can imagine high fever, depression, anorexia. I have heard this disease being described as the Ebola virus of the pig world. Liz would you say that that sounds.
Yeah so the the reports initially of the cases in China and people that were overseas seeing it over in those situations where it's a slow burn usually in the period, so it starts off as just a few, you know cases which could be mistaken for traditional pig problems, I guess as a life, but then they went out the next morning or four days later and they had an entire pen. Either dead or lying down and if you try and disturb them, some of the videos I've seen - if any of you have walked into a piggery, the whole pen gets up and wants to find out what the heck's going on but in the cases where it was clinical in these farms the pen, it took a lot to rouse them and get them on their feet and if you turned your back within 30 seconds soon so, when it hits that high peak level, you'll very much know something's wrong but it can be mistaken early while it's building up enough momentum in the piggery.
Yeah, so you do get haemorrhages in the skin, it can cause abortions and it's mortality rates up to 100%, so obviously this is one of the main reasons why ASF would be such a huge financial burden to the pork industry in Australia.
Again, lots of differentials and you know these differentials are probably more likely to be the cause of any of these signs that you see, but please let us know if you're seeing these signs so we can do an ASF exclusion test.
African horse sickness, has really started to spread into our part of the world traditionally obviously mainly seen in Africa, but with the spread of it being vector-borne it has come across to various parts of Asia it's a highly pathogenic arbovirus, so spread by midges.
It can cause severe often fatal circulatory and respiratory disease. Horses are obviously most severely affected, but all equine species: donkeys, mules, zebras - they're all susceptible to it. Disease with mortality has been observed in dogs following ingestion of infected meat material and the virus, it survives a few hours in carcasses but it's pretty easily inactivated once the animal starts to decompose.
This is the spread of it, so as I said, Africa was the main location for it for many years, but it has started to spread and then we've started to see cases of it - I think that's Malaysia, no Thailand. Thailand. It's hard to see from this angle.
Clinical signs of African horse sickness are pretty distressing, especially as we know horse owners in particular love their animals, so this would be devastating for them to see. There's four recognized clinical presentations: there's horse sickness fever which occurs in previously exposed immune horses with just mild fever malaise and you get this oedema above the eyes too, but if it came into Australia, obviously because it's not here at the moment we would probably see more marked clinical signs than this.
So there's the cardiac form where the horses will get a fever and subcutaneous oedema. Oedema is the main clinical sign, with a mortality rate of up to 50%. Now, the pulmonary form where they get markedly depressed, to fever, severe dysponeia, spasmodic coughing, nasal discharge and a mortality rate of 95%.
There's quite a few viruses that need to be excluded if you are going to see a horse like this. This is where you will want to use the PPE in the kits that you will be receiving this afternoon, because something with signs like this and if you put neurological signs on top of it, you'd be wanting to do a Hendra exclusion so please make the use of those PPE kits that you'll be getting at the end of the day.
The mixed form is the most common form that's a combination of both cardiac and polymerase pulmonary science, with a mortality rate of up to 80%, so these are those differential diagnosis. As I said Hendra virus is probably from a zoonotic point of view, the one that we want to be careful for and the one that we're really looking out for in this region. We haven't had any cases of Hendra in our region but it's always important to do exclusions.
The last one on the list is highly pathogenic Avian Influenza which has come into Australia previously, but we've managed to eradicate each time it's come in. Again, it's a highly infectious viral disease. We're starting to see a pattern here I think, humans are susceptible to Avian Influenza which I'm sure most of you are aware of. There is low pathogenic and high pathogenic; we've had eight outbreaks since 1976. The most recent one was in Victoria in 2020 and it was around Young and Cowra was it 2013?
Yep.
Outbreaks are likely to occur via wild birds contaminating water or food supplies for poultry, or directly contaminating range areas. So free range farms in particular are at high risk given their exposure to wild birds and obviously it's very hard for us to control wild bird migratory populations.
Infection spreads through the movements of infected live birds or fecally contaminated eggs, feed equipment materials, clothing and footwear.
As you can see, there are a few events that have gone on recently. I can't see anything going on in Australia at the moment which is always good and I was hoping that there wouldn't.
The clinical signs of the peracute form are really just birds dying suddenly. If you're not confident with doing bird post mortems - is there anyone from EMAI still here? I might get in trouble for saying this - you can send them whole birds if you're not confident in sampling. I know some of my district vets have done that. The acute form is severe respiratory signs, cyanosis, oedema, ischaemic necrosis of the cones and wattles, haemorrhages, ocular and nasal discharges, egg drop syndrome, a sudden decline in feed and/or water consumption.
As you can see, they're pretty non-specific signs, so it could be a number of things occurring, but again and I'm going to keep saying it - always important to do exclusions because that's the only way that we're going to find out if we do have something like this as an outbreak.
Subacute and chronic forms are: respiratory signs, discharges, swollen sinuses, decreased egg production, morbidity and mortality is quite low in these subacute and chronic forms.
Again, a very long list of differential diagnoses that we have to consider. Most of these are obviously much more common but again we need to rule it out. There's that number again, I told you you'd see it lots of times today. So look, early detection is critical.
As I said, at the beginning of the talk, we have District Vets throughout the Riverina but we also rely on private vets because you guys are out there as eyes and ears, and all the other senses out on farms. You're seeing much more of what's going on, you're more likely to do routine visits to farms and we are and can pick up on things that farmers might have overlooked. So we need you to be alert to these things so you can do an investigation for those and we're always here to help you, so over the phone the 1-800 number - get the phone number of your local District vet or that 1300 number.
That will go through to one of our offices and you'll get the number from there. So yeah, if you need any help if you're out in the field and you need a hand, ring your District's Vet or ring that 1-800 number and we can certainly be of help with the samples that you have to collect. The next steps to take. Please make sure you take all your equipment with you when you go out on calls, in case you need to gown up into PPE gear and after today you will all be experts in that too.
