Technical developments in FMD control: 10 years after the 2001 epidemic in North-West Europe
On the 20th of February 2001, FMD was diagnosed in the UK. The rapid spread, with infection reaching three other European countries, and scale of the response, and the costs to all sectors of the economy of the UK, Ireland, Netherlands and France, and which also affected the trade of other European countries, resulted in impacts that are still felt 10 years later.
We asked the EuFMD Research group to highlight progress in the past 10 years on the technical issues that affected control of FMD in 2001. Their responses have been collated and a summary made by the EuFMD Secretariat.
Hot issues in 2001
• Delayed detection of initial cases;
• Traditional "tracing and stamping-out" vs extended area (ring) culling around infected premises;
• Fear of uncontrollable spread (long distance aerosol transmission from pig farms);
• Stamping –out; the risks associated with failure to meet targets for rapid culling;
• Diagnostic delays and their impacts (slaughter of herds on suspicion, and delayed culling), and the "non-use of penside tests including portable PCR laboratories";
• Pre-emptive culling of animals on contiguous premises, and wider "ring" culling;
• Use of vaccination, its impact as an additional control measure and the effect on post-vaccination trade and livelihoods of livestock producers;
• International (OIE) standards "penalising" the use of vaccination (12 month waiting period versus 3 months if stamping out used);
• Decision making processes in disease management, local veterinary risk based decision making versus national, and the role of "expert groups" and academic experts;
• Preventing it happening again; import controls, swill feeding, and the lack of disease control in "FMD endemic countries".
Major events or developments in past 10 years
• on reducing the danger period of delayed detection; changes include regulating animal movements to reduce number of farm to far movements of an animal within a set period, so to reduce number of contacts during a danger period;
• On variations in stamping out policies; re-examination of culling and vaccination options, leading to better definition of circumstances where each may provide most benefit ; contingency planning and simulation exercises to review capacity to deliver and resource management to achieve policy goals; greater involvement of stakeholders in reaching agreement on disease control policy goals in contingency planning;
• Greater appreciation that uncontrollable spread may be a rare event, and its occurrence predictable (although virus strains differ in risk of high aerosol production and this property is not well understood or predicted) and that FMD control at local level is largely through biosecurity breaches that are potentially controllable;
• Resource optimisation models that assist decision makers to better identify critical resources needed at each phase of disease control operations, such as resources for culling and disposal; management options for calling up resources at short notice; but rapid scale up of stamping-out inevitably is an enormous challenge;
• Diagnostic delays; high throughput molecular assays for confirming infection, and pre-clinical screening in surveillance; rapid, penside tests for field use in confirmation of secondary cases, although only acute stage infections reliably detected at present;
• Pre-emptive culling; better recognition of farmer reporting and veterinary surveillance performance problems, and the role/feasibility of preclinical screening, has helped to define risk of spread to contiguous premises or high risk tracings, and circumstances for pre-emptive culling;
• Vaccination; changes in OIE and EU standards have created an more favourable enabling environment for use of vaccination as additional control measure;
• The performance and validation of NSP tests for use in post-vaccination surveillance is now widely accepted to be "fit for purpose" , commercial assays are now available, and their performance comparable to the OIE reference test;
• The ability to regain free status after vaccination, and fate of vaccinated animals, has been assisted by development, validation and testing in simulation exercises to define and largely resolve post-vaccination surveillance issues;
• Decision making processes in disease management; emphasis on contingency planning, regular simulation exercises of sufficient rigour to test capacity to respond, and scaling up human and other resources to achieve greater use of local, risk based control measures; aided by improved identification and registration systems; against this is the trend to reduced veterinary field services and farm based veterinarians able to manage complex, risk based priority setting in disease management;
• Expertise and use in decision making; the use and limitations of epidemic modelling are now better appreciated, but expertise in FMD management, and FMD science, remains relatively limited; the EuFMD with EC support has trained over 80 veterinarians from about 30 European countries as front line FMD response investigators, to assist initial local response management. The pool of European expertise in FMD remains similar to 2001 and the new generation have benefitted from the boost in R&D funding post-2001, but this may now be at risk;
• FMD virus circulation in endemic countries is probably at a incidence similar to that occurring before 2001, and very few advances have been made in endemic regions; the European ban on waste food/swill feeding to pigs has been arguably the one single measure of greatest risk reduction that has occurred, and rates and routes of illegal infected product entry into the EU remain hard to quantify;
• The Global Foot-and-Mouth Disease research Alliance (GFRA) has been a positive development since 2001, that connects advanced FMD research laboratories across the globe and acts to increase awareness of the potential for rapid gains in technical areas including vaccine development, needed by FMD endemic as well as free countries, and has stimulated FMD research and some highly innovative and promising developments, especially in vaccine development;
• The FAO/OIE FMD reference laboratory network has since 2005 provided services and information vital for national and international risk managers, particularly in vaccine selection and on new epidemic movements and patterns, and assisted to define 7 FMD virus pools that make up the global distribution, leading to the concept of Regional Roadmaps to address the seven different and unique virological pools in Eurasia, Africa and South America;
• The FAO/EuFMD Progressive Control Pathway for FMD, used since 2008 to develop regional Roadmaps to improved FMD control in endemic regions, provides an important tool to develop long term national to regional control programmes. The PCP-FMD is expected to be the mainstay of a global effort (FAO/OIE) to improve national FMD control in endemic regions in the next 10 years.
The fact that the EU has only seen very small outbreaks of FMD since 2001 does not mean it cannot happen again. Challenges remain, particularly as the livestock sector changes and fewer people are engaged in daily animal care or in state veterinary services, which creates risks for delayed reporting and potentially larger outbreaks managed at first by fewer persons. The use of vaccination in disease control is an option with fewer negative economic impacts than before, but there is still not an equal waiting period after outbreaks to regain recognised freedom. Vaccination requires large scale banks of antigen for use in emergency and work is needed to develop new generation options for rapid onset immunity to enable a larger scale vaccination should an incursion threaten to overwhelm other containment measures.
One of the major risk reductions for the future will be the control of FMD in endemic regions. This will be the next main step forward in FMD control. Small steps are being taken, with the development of the Progressive Control Pathway as the most significant one. For the EU, investment in development of new stable and easy to use vaccines that can be deployed in endemic countries should be the next step. Not only the development of these vaccines but also the coverage of old and new vaccines have against the ever changing FMD strains will be one of the future challenges for FMD research.