FMD: ‘The virus does not care about factions or blame-shifting’

There has been an acceleration of noise concerning the management of the foot-and-mouth disease (FMD) outbreak in South Africa and it is essential that we focus back on where we are, forget about where we’ve been and constructively move forward to stop further spread of this virus.

By Dr Anthony Davis

The following points are intended to cut through some of the noise and raise the point that no matter what industry we may find ourselves in, the impact of the rampant spread of foot-and-mouth disease is massive and requires concerted, constructive and united effort to stop it. Court cases are not helping. Blame-shifting is not helping. We have what we have and immense progress has been made to stem this tide. This is not a time to divide into factions. This virus does not care about factions. It cares about spreading. We cannot afford division.

There are enough resources and there is enough will in this country to deal with this outbreak but this requires clear focus and strong strategy. Vaccines are now being rolled out faster than before, there are systems available to manage the logistical requirements and there is a national urgency to fix this. Resources are currently limited. We must work with what we have.

We don’t need to make this complicated: Vaccinate around high-risk areas and outbreaks, control movement and practice good biosecurity. Applying this is inconvenient and comes at a cost, but we will never get away without these three fundamental pillars of FMD control, even if we get to a point where widespread vaccination is possible. This is not a disease that can be controlled by vaccination alone.

Also watch: Weekly RMIS FMD update: Vaccine supply and strategic planning

Dr Anthony Davis busy vaccinating cattle with the Biogénesis Bagó vaccine. Photo: Supplied

Vaccination must be targeted, effective and accompanied by supportive control measures:

Private vets, in agreement with State Veterinary Services, have been vaccinating cattle with the FMD vaccine for the past two months. This has sped up the process of vaccine administration and has increased the reach of State services to roll out vaccines to high-risk areas.
Earlier this month, based on reported cases of outbreaks, the vaccine requirements calculated by the risk-based model was that 2.5 million cattle were within 10km of an outbreak. This is an under-representation because not all cases are reported, but it does provide a crude estimate of what we are up against. The rollout of 2.5 million doses of vaccine, as has happened, allocated to areas of high risk, will go a long way to controlling many of these outbreaks. The immense benefits of working according to a risk-based model, especially when vaccine supply is limited, is the only effective approach to put these FMD fires out. Vaccinating a 10km radius around an outbreak is an effective strategy to reduce further spread of the virus. The other two essential pillars of FMD control – biosecurity and movement control – must be practiced in conjunction with this vaccination drive.
Vaccine efficacy is not only determined by matching data. There is cross reactivity within the types that will not be detectable from matching data. Vaccine potency can compensate for an imperfect match. The Target Product Profile developed by MTT vaccine experts utilised a set of criteria that included vaccine matching but this is by no means the only other requirement. FMD vaccines are inactivated vaccines, so there must be assurance that the vaccine manufacturer has taken the necessary quality control steps to be sure that vaccine is properly inactivated. Based on these criteria, when new vaccine candidates were considered, this left only two reliable new vaccine candidates: Biogénesis Bágo and Dollvet. It is not true that millions of doses of vaccine were available for import. It is true that these companies can produce millions of doses per month, but not the vaccine that we need. The vaccine we need must be as well matched as possible to cover the circulating strains but must also tick the boxes of the other quality criteria stated in the TPP. It is also necessary to test this vaccine under field conditions, and it would be irresponsible to import a large consignment until we have assurance from field experience that the vaccine is effective, reliable and safe.
FMD vaccines do not prevent infection. They prevent clinical disease, so even if you vaccinate, the disease can still spread through a herd of cattle. The vaccine will reduce viral shedding, which is why it has become popular practice, especially on dairy farms, to vaccinated infected herds to reduce the impact of the infection. This is not like any other disease we have experienced in this country. This is the most contagious virus on the planet.
Traceability is a key component of FMD management. If animals are tested serologically, it must be possible to interpret a serologically positive test based on vaccination history. Movement of animals is impossible without reliable traceability. We are fortunate to have several traceability systems and all of these can be used effectively for this purpose.
FMD management has always required extensive paperwork and permissions. These can be effectively streamlined by moving towards electronic database programs that effectively speed up the process. This technology is available and must be used.
We cannot get away from the fact that foot-and-mouth disease is a disease of regional and international concern. We cannot get away from the fact that we need a thriving export market. International guidelines/legislation is in place to protect countries from foot-and-mouth disease. There are stringent criteria that must be met to facilitate trade. Our current goal is FMD-free with vaccination. FMD-free without vaccination means we need to prove that there is no circulating virus, which requires surveillance, both passive surveillance that requires honest reporting, and active surveillance that requires physical inspections accompanied by laboratory testing. All of this adds to the cost. The sooner we get this disease under control, the sooner we can start moving towards our goal. We cannot accept endemic status, not in South Africa. In certain provinces, the infection is so widespread and severe that there is little choice but to deal with the disease in this way.
We must protect our game industry. We must prevent this disease from further depleting genetic reserves and destroying production potential. We do not need to throw in the towel and accept endemic status in all areas of the country. In parts of the Eastern and Western Cape where dairy farms predominate, we cannot co-exist with this disease. It has too many implications for movement control, milk processing restrictions and a devastating clinical impact that is simply best avoided. Dairy producing areas want this disease gone, and although vaccination will be useful now for peace of mind and to prevent surprise outbreaks, this will not be an effective long-term strategy for dairy farms. Mass vaccination is a good way to stop further spread, but even then, the aim should be to be very focused and to not ‘hide’ the virus by over-vaccinating. The only way to do this is to follow a risk-based approach, using known and discovered epidemiological risk factors and to drive the vaccine rollout through State Veterinary Services in partnership with the private sector. This partnership must bring tools to the table to extend the reach, facilitate document management, monitor and control movement, actively enhance laboratory capacity and develop new surveillance tools. New diagnostic and surveillance options must be developed and validated in a field setting.
Foot-and-mouth disease can and must be overcome, for the sake of every livestock owner who understands the extent of this threat and to every entrepreneur that sees a future for themselves to invest in agriculture.

Dr Anthony Davis is a veterinarian in private practice focused mainly on dairy herd health. He has a master’s degree in Veterinary Tropical Diseases and is in the final year of a PhD degree at the University of Pretoria. He has been involved in two FMD outbreaks in the Eastern Cape and has served on the ministerial task team. He is also working on a project in collaboration with the ARC and the Pirbright Institute on FMD viral load in milk.

Disclaimer: The opinions expressed in this article are those of the author and do not necessarily reflect the views of African Farming.

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