2007년 영국 퍼브라이트 연구소(Pirbright Laboratory) 소속 연구자들은 O1 Manisa주 백신접종을 한 후 O1 UKG을 투여하여 면역성을 실험했습니다.

백신 접종 후 10일째  O1 UKG주를 투여한 돼지 중에서 81%가 구제역 임상증상을 나타냈으며, 백신 접종 후 29일째 O1 UKG주를 투여한 돼지 중에서 25%가 구제역 임상증상을 나타냈습니다. 

비록 백신접종이 임상적 및 바이러스학적으로 완벽한 방어를 나타내지 못했으나, 질병의 중증도를 감소시키고, 바이러스의 분비를 줄였으며, 비구조적 구제역 바이러스 항체를 생산하였고, 그 이후에 돼지를 감염시켰습니다고 합니다.
 

Reduction of foot-and-mouth disease (FMD) virus load in nasal excretions, saliva and exhaled air of vaccinated pigs following direct contact challenge.

Parida S, Fleming L, Oh Y, Mahapatra M, Hamblin P, Gloster J, Doel C, Gubbins S, Paton DJ.

Institute for Animal Health, Pirbright Laboratory, Ash Road, Pirbright, Surrey GU24 0NF, United Kingdom. satya.parida@bbsrc.ac.uk

Vaccine. 2007 Nov 7;25(45):7806-17. Epub 2007 Sep 17.

호주정부는 구제역이 아주 드물게 인간에게 전염되지만 증상은 아주 약하다. 구제역은 공중보건 상의 문제로 고려되지 않는다.( People are rarely affected by FMD virus and if so, the symptoms are mild. FMD is not considered a public health problem.)고 자국의 국민들에게 확실한 과학적 정보를 제공하고 있습니다.

구체역의 인체 감염은 구제역에 감염된 가축을 다루는 중에  또는 실험실에서 피부 상처를 통해 일어날 수 있으며, 구제역에 감염된 우유를 마시면서 입을 통해서 일어날 수 있다(Infection can occur through skin wounds by handling diseased stock or the virus in the laboratory (no Australian laboratory holds infective FMD virus), or through the mouth lining by drinking infected milk.)는 사실도 공개하고 있습니다.

이러한 과학적 정보를 제공한 후에 감염된 가축의 고기를 섭취하거나 다른 축산제품을 소비함으로써 구제역에 감염되지는 않는다고 밝히고 있습니다.

그리고 구제역의 인체감염은 일시적이며, 경증이고, 아주 드문 경우에만 임상적으로 질병(열, 손과 발 또는 입에 수포)이 나타난다는 사실도 알려주고 있습니다.

호주 정부의 구제역 방역의 기본 방침은 살처분(stamping out)이며, 특정한 상황에서 백신정책을
도입할 수 있다고 밝히고 있습니다. 그럼에도 불구하고 구제역 백신접종을 한 동물들을 모두
살처분한다고 분명히 밝히고 있습니다. 호주에서는 구제역 백신 접종 후 그 동물들을 살리기 위한
보호적 백신(protective vaccination)을 금지하고 있습니다.

FMD FAQs

출처 : http://www.animalhealthaustralia.com.au/programs/eadp/ausvetplan/fmd-response-policy-review/fmd-faqs.cfm

1.       What is FMD?

Foot-and-mouth disease (FMD) is an acute, highly contagious and rapidly spreading viral disease of domestic and wild cloven-hoofed animals such as cattle, pigs, sheep, goats, camelids (camels, llamas and alpacas) and buffalo.

The disease is characterised by the formation of vesicles (fluid-filled blisters) and erosions in the mouth and nostrils, on the teats, and on the skin between and above the hoofs. The disease spreads extremely rapidly through populations of susceptible animals. FMD may cause serious production losses and is a major constraint to international trade in livestock and their products.

Mortality in adult cattle is usually low to negligible, but up to 50% of calves may die.  Significant mortality can also occur in piglets, and although the disease is usually mild in sheep and goats, significant mortality can occur in lambs.

There is no specific treatment for FMD. With severe disease and particularly if there are severe secondary infections and complications, animals may have to be culled because of welfare reasons.

2.       What is Australia’s FMD status?

Australia is free from FMD; FMD is ‘exotic’ to Australia.

Minor outbreaks of possible FMD occurred in 1801, 1804, 1871 and 1872. The last incident occurred in Victoria following the importation of a bull from England. Two farms were involved before the disease was eradicated. FMD has not been diagnosed in Australia since then.

3.       Why are we so worried about FMD?

An FMD outbreak would result in the immediate closure of many of Australia’s major export markets for livestock and livestock products.

The economic effects of an outbreak of FMD, even on a small scale, would be enormous to individuals, to the farming industry as a whole, and to subsidiary and support industries.

There would be significant flow-on losses to the economy, including to many businesses that rely on livestock industry revenue in rural and regional Australia. In 2002, the Productivity Commission concluded that, overall, the estimated cumulative loss to the national economy would be about $2–3 billion in gross domestic product for a short outbreak, rising to $8–13 billion for a 12-month outbreak.

4.       Where in the world does FMD occur?

FMD is endemic throughout the Middle East, Africa, Asia and most of South America.

Among Australia’s closest neighbours, Indonesia, Singapore, Papua New Guinea, New Zealand and the Pacific island nations are free from FMD. Parts of Malaysia are also free. However, FMD is found as close to Australia as in parts of the Philippines.

5.       What is Australia doing to keep FMD out of livestock?

Australia has strict quarantine controls in place to keep FMD out. There is also a ban on feeding swill to pigs and strong encouragement of on-farm biosecurity practices.

Australia does not allow imports of any susceptible live animals, semen or uncooked meat or unprocessed dairy products from FMD-affected countries or zones.

Australia also invests in other activities ‘at source’. For example, Australian overseas aid programs include an FMD eradication campaign in Southeast Asia (OIE Southeast Asia Foot and Mouth Disease Campaign) and a specific FMD control program in the Philippines. The Australian government also runs the Northern Australia Quarantine Strategy, aimed at early detection of exotic disease in high-risk areas of northern Australia. The strategy has an offshore component that includes periodic disease surveys in West Papua, Timor-Leste and Papua New Guinea. These activities provide added knowledge and assist in risk management.

Pigs shed about a thousand times more virus than other susceptible animals and are the major amplifying host for the disease. Pigs are mainly infected through eating contaminated meat products but are then very efficient at multiplying and spreading the virus through aerosols, thus spreading the disease to other animals. Many FMD outbreaks have originated from swill feeding of pigs with infected animal products or meat scraps from infected animals.  It is illegal to feed swill to pigs in Australia.

Transmission occurs most readily when animals are in close proximity, such as at watering and feeding points, stockyards and milking sheds. Spread of infection between properties and areas is often due to the movement of infected animals or contaminated vehicles, equipment, people and products. Infected animals can shed virus up to four days before clinical signs become apparent so animal movement can be a big factor in the spread of FMD. Simple on-farm biosecurity measures can minimise the risk of spreading disease, including FMD.

6.       Given FMD is exotic to Australia, how could we get it in?

The most significant risk of entry of FMD to Australia is through illegal entry of meat and dairy products which could find their way into the livestock population.

The virus can survive for long periods in a variety of fresh, partly cooked, cured and smoked meat products, and in inadequately heat-treated dairy products which could find their way into the livestock population and cause an outbreak of FMD (as happened in the UK in 2001). These could be brought in by passengers on aircraft or ships, or could be sent through the post. There is also a risk from garbage discarded by fishing vessels or yachts.

7.       How easy would it be for FMD to spread in Australia?

FMD has the potential to become established in Australian cattle, pig, sheep and goat populations; unless diagnosed and responded to very early, FMD could spread rapidly throughout Australia especially through movement of infected livestock.

Australia has large populations of domestic and feral animals that are fully susceptible to infection with FMD virus, including intensively managed animals in dairies and piggeries, animals in more extensive cattle and sheep enterprises, and feral pigs, cattle, goats, camels and buffalo.

Long-distance windborne spread of infection, except where piggeries are involved, is unlikely in most, if not all, of the country. However, the disease could be spread very rapidly through livestock saleyards, and by the movement of animals, contaminated trucks or other items.

8.       Can people get infected with FMD virus?

People are rarely affected by FMD virus and if so, the symptoms are mild. FMD is not considered a public health problem.

Infection can occur through skin wounds by handling diseased stock or the virus in the laboratory (no Australian laboratory holds infective FMD virus), or through the mouth lining by drinking infected milk. People cannot be infected by eating meat or consuming other products from affected animals.

The infection is temporary and mild, only very occasionally resulting in clinical disease (fever, vesicles on the hands, feet or in the mouth). 

‘Hand, foot and mouth disease’ of humans (most often caused by Coxsackievirus type A16) is present in Australia and may be confused clinically with FMD; it is not the same disease.

9.       What would we do if we had an outbreak of FMD?

FMD is highly contagious and Australia’s control and eradication procedures include strict movement controls and the destruction of infected and at risk animals.

Australia’s response policy for an outbreak of FMD is to control and eradicate the disease through stamping out and to re-establish the FMD-free status of Australia as quickly as possible. It is described in detail in AUSVETPLAN, Australia’s Veterinary Emergency Plan [link to AUSVETPLAN].

Stamping out involves culling of all susceptible animals on infected premises and dangerous contact premises, regardless of whether the animals are infected or not. ‘Susceptible animals’ would include all cattle, pigs, sheep, goats and camelids on those premises.

Our response policy to an FMD outbreak also states: ‘Although it could extend market disruption, vaccination may be used in certain circumstances (for example, if the disease spreads beyond the limit of the available resources to control it; or to protect large animal concentrations, limit infection and minimise virus production)’; however, it qualifies that ‘Vaccinates must ultimately be slaughtered out’, essentially not permitting protective vaccination (‘vaccinate to live’).

Vaccination FAQs

출처 : http://www.animalhealthaustralia.com.au/programs/eadp/ausvetplan/fmd-response-policy-review/vaccination-faqs.cfm

1.       Are there FMD control options other than stamping out?

Yes. Especially since the FMD outbreak in the United Kingdom in 2001 when almost 6 million cattle were culled, research into FMD has offered alternative options, such as protective vaccination, for responding to an outbreak of FMD.

The FMD outbreak in the United Kingdom in 2001 was the largest in history. The UK eradicated FMD by stamping out the disease, but suffered losses of more than eight billion pounds sterling (approximately A$19 billion); the country’s livestock and tourism industries were devastated as a result.

In the same year, Uruguay also suffered an outbreak of FMD. Uruguay’s cattle population was the same as that of the UK and the number of infected herds was almost identical. However, while the UK used stamping out on its own and killed a total of 5,730,000 cattle (with 3,910,000 testing positive to FMD), Uruguay used protective vaccination (‘vaccinate to live’) to assist its eradication campaign and needed to kill only 6,937 cattle (all FMD positive).

The direct cost of the FMD outbreak in the UK was US$4.6 billion, that of Uruguay US$13 million. The total economic impact of the FMD outbreak in the UK was over US$10 billion, that of Uruguay less than US$400 million.

2.       Why would vaccination be considered in an FMD outbreak?

Vaccinating animals can ‘buy some time’ because it can delay or even prevent further spread of disease from the known outbreak locations.

The Australian response policy for an outbreak of FMD is to control and eradicate the disease through stamping out. Time is the essence here; if there are delays in carrying out the slaughter, the effectiveness of this approach is not guaranteed, and the disease can spread out of control.

There are two principal options for vaccination: protective vaccination (‘vaccinate to live’) and suppressive vaccination (vaccinate to die’). For their respective advantages and disadvantages see relevant questions.

3.       What  does ‘vaccinate to live’ mean?

‘Vaccinate to live’, more appropriately called ‘protective vaccination’, means that an animal is vaccinated against a disease for the purpose of protecting it from getting ill and possibly dying. If used as part of an FMD eradication campaign, protective vaccination greatly reduces livestock losses because fewer animals get sick or need to be killed.

Protective vaccination is what is commonly used to protect people and animals from infectious diseases, e.g. measles, influenza, tetanus. People and animals are vaccinated when they are healthy, as a measure to prevent a future infection. In an FMD outbreak, ‘ring vaccination’ would be used, that is healthy animals in a, for example, 5 km radius around an infected premises would be vaccinated to provide a ‘buffer population’.

4.       What does ‘vaccinate to die’ mean?

‘Vaccinate to die’, more appropriately called ‘suppressive vaccination’, has the purpose of minimising or stopping virus shedding and  ‘buying time’ in the eradication campaign. It may protect the animal against clinical disease, but it will not necessarily prevent infection.

Animals to be vaccinated under this strategy are usually those at high risk of infection, literally the ones in the middle of the outbreak. If suppressive vaccination is used as part of an FMD eradication campaign, all vaccinated animals will be killed at the end of the eradication campaign.

5.       How would we use vaccination? For example, would all susceptible animals be vaccinated?

The exact vaccination strategy would depend on the circumstances of the outbreak but the key parameter would always be to quickly and effectively control the outbreak with a view to restoring business continuity.

Typically, if suppressive vaccination (‘vaccinate to die’) is used, animals to be vaccinated are those at high risk of infection, literally the ones in the middle of the outbreak. This is because the purpose of suppressive vaccination is to ‘buy time’ in the eradication campaign, that is to ‘suppress’ the spread of infection.

If a strategy of protective vaccination (‘vaccinate to live’) is followed, ring vaccination is typically used. This means that animals within a certain radius around infected premises are vaccinated so that a buffer population of vaccinated animals surrounds the infected premises, helping contain the outbreak and prevent it from spreading to the outside of the ring.

6.       Why do vaccinated animals need to be killed if suppressive vaccination is used as part of an FMD eradication campaign?

Depending on the time between vaccination and infection, vaccinated animals may not show clinical signs, but they may still carry the virus. That is why even those vaccinated animals are ultimately killed.

The purpose of suppressive vaccination is to ‘buy time’ in the eradication campaign, that is to ‘suppress’ the spread of infection. Animals to be vaccinated under this strategy are usually those at high risk of infection, literally the ones in the middle of the outbreak. If they’re not infected already, they’re expected to become infected. Depending on the time between vaccination and infection, they may not show clinical signs, but they may still carry the virus. That is why even those vaccinated animals are ultimately killed.

Emergency vaccination of at-risk stock (suppressive vaccination, ‘vaccinate to die’) may result in the need to destroy animals that would otherwise have avoided destruction in a conventional stamping-out approach.

7.        What are the advantages and disadvantages of protective vaccination in an FMD outbreak?

One advantage is that – while eradication is still achievable and remains the goal – far fewer numbers of healthy animals need to be killed to achieve eradication, reducing not just livestock losses but also collateral damage to e.g. commercial activity in rural locations. On the downside, concern is sometimes expressed that the use of protective vaccination doubles the waiting period required to regain the OIE status of FMD free country when compared to stamping out or stamping out with suppressive vaccination (6 months versus 3 months).

Using protective vaccination as part of the eradication campaign also means there are fewer resources required to kill animals and safely dispose of the carcases.

Not having to kill large numbers of healthy animals would attract wide community support.

Regarding regaining freedom from FMD, in reality, the OIE does not determine the length of trade exclusion. The point in time following eradication of FMD when export trade resumes will be determined between Australia and its trading partners; regardless what eradication strategy is chosen, exclusion of some commodities from some export markets will most likely last for at least 12 months.

8.       Has protective vaccination ever been used effectively in an FMD outbreak?

Yes, for example by Uruguay in 2001, the same year that the UK had an FMD outbreak and used stamping out on its own. The Uruguay outbreak lasted 18 weeks, half as long as the UK outbreak, and the total economic impact was less than 4% of that in the UK.

Uruguay’s cattle population was the same as that of the UK at the time of the 2001 outbreak and the number of infected herds was almost identical. However, while the UK used stamping out on its own and killed a total of 5,730,000 cattle (with 3,910,000 testing positive to FMD), Uruguay used protective vaccination to assist its eradication campaign and needed to kill only 6,937 cattle (all FMD positive).

The direct cost of the FMD outbreak in the UK was US$4.6 billion, that of Uruguay US$13 million.

The total economic impact of the FMD outbreak in the UK was over US$10 billion, that of Uruguay less than US$400 million.

9.       Does Australia have FMD vaccine available?

In Australia, governments and livestock industries have invested in FMD vaccine supply arrangements.

A supply contract with a commercial manufacturer has been secured over 5 years (ending in 2014) to provide 500 000 cattle-equivalent doses of any of nine FMD strains within 7 business days of notification. This number of doses has been calculated to be sufficient in the early stages of a response but will be supplemented by further purchases if needed.

10.   What are ‘DIVA tests’?

DIVA stands for ‘Differentiating Infected from Vaccinated Animals’.

If animals are vaccinated against FMD, they will – for a period of time – give a positive result in blood tests. However, the animal could also be infected with ‘real’ FMD virus. Standard tests cannot tell the difference between a positive result due to vaccination and a positive result due to actual FMD infection.

FMD DIVA tests are tests that can determine whether an animal that tests positive to FMD screening tests does so because it is infected with FMD virus or because it is vaccinated.

11.   What is the relevance of ‘DIVA’ testing for FMD vaccination?

DIVA tests are needed to demonstrate FMD disease freedom after an FMD outbreak has been eradicated when protective vaccination has been part of the response.

Before we can claim success that we have eradicated an FMD outbreak, we need to demonstrate that there are no animals left that are infected with FMD virus. This is done by laboratory tests of samples taken from animals in the ‘proof of freedom’ phase after the outbreak.

If animals are vaccinated against FMD, they will – for a period of time – give a positive test result for FMD.

Under Australia’s current FMD response policy, suppressive vaccination (‘vaccinate to die’) is possible under certain circumstances. Under that policy, all vaccinated animals would be killed during the eradication campaign, that is, there would be no vaccinated animals still alive in the ‘proof of freedom’ phase. Therefore, any animals testing positive in the ‘proof of freedom’ phase would be considered as infected (which means eradication wasn’t as yet successful).

If vaccinated animals have been allowed to live (‘vaccinate to live’; protective vaccination), standard tests cannot tell the difference between a positive result due to vaccination and a positive result due to actual FMD infection. This is where DIVA tests are required, that is, tests that differentiate infected from vaccinated animals.

12.   How long would it take for Australia to regain its FMD-free status after an outbreak?

The World Organisation for Animal Health (OIE) recognises Australia as a country ‘free from FMD without vaccination’. According to the OIE standards, the waiting periods – after a successful eradication campaign – required to regain the OIE status of FMD free country are 3 months when stamping out or stamping out with suppressive vaccination (‘vaccinate to die’) has been used, and 6 months when stamping out with protective vaccination (‘vaccinate to live’) has been followed.

For Australia to regain its FMD-free status as quickly as possible (in 3 months rather than 6 months), it would be necessary for a stamping-out policy to apply and – if suppressive vaccination has been used – for all vaccinated animals to be destroyed, in line with the OIE standards. Emergency vaccination of at-risk stock (suppressive vaccination, ‘vaccinate to die’) may result in the need to destroy animals that would otherwise have avoided destruction in a conventional stamping-out approach.

In reality, the OIE does not determine the length of trade exclusion. The point in time following eradication of FMD when export trade resumes will be determined between Australia and its trading partners; regardless what eradication strategy is chosen, exclusion of some commodities from some export markets will most likely last for at least 12 months.