Foot‑and‑Mouth Disease: Global Threats, Transmission and Prevention
Introduction
Foot‑and‑mouth disease (FMD) is one of the most contagious diseases affecting cloven‑hoofed animals such as cattle, pigs, sheep, goats and various wildlife[1]. Although the virus is not considered a threat to human health[2], outbreaks devastate animal agriculture by reducing productivity, triggering trade bans and forcing mass culling. Visible production losses and the cost of vaccination programmes in endemic regions alone are estimated to cost up to USD 28 billion annually[3], and when trade disruptions are added the global burden climbs even higher. As a transboundary animal disease recognised by the World Organisation for Animal Health (WOAH) and Food and Agriculture Organization (FAO), FMD can reach 100 % morbidity in unvaccinated herds and affects about 2 % of the world’s cattle population each year[4]. Understanding the virus, how it spreads and how to prevent it is essential for veterinarians, producers and animal health students around the world.
This article explains the FMD virus and its serotypes, identifies the species most at risk, outlines the main transmission routes, describes clinical signs and economic impacts, and summarises science‑based prevention and global control strategies. It follows the style of Maizer’s in‑depth technical guides, balancing scientific detail with actionable biosecurity advice.
What Causes FMD? Virus Overview & Serotypes
FMD is caused by foot‑and‑mouth disease virus (FMDV), a member of the genus Aphthovirus (family Picornaviridae). There are seven distinct viral serotypes: O, A, C, SAT1, SAT2, SAT3 and Asia 1[5]. Each serotype requires a specific vaccine because immunity to one does not protect against the others. Serotype C has not been isolated by the network of WOAH/FAO reference laboratories since 2004, suggesting it may be extinct[5]. However, the other six serotypes circulate widely in different geographic regions.
The virus is extraordinarily resilient. It can survive for prolonged periods in the environment and persists in animal tissues and secretions. African buffalo (Syncerus caffer) are notable wildlife reservoirs that can carry FMDV without showing disease[6], posing a persistent risk of re‑introduction to domestic herds. In cattle and other domestic species, some recovered animals may harbour the virus and act as carriers, shedding virus intermittently and igniting new outbreaks[7].
Host Range and Lack of Zoonotic Risk
FMD affects a wide range of cloven‑hoofed livestock. The primary domestic hosts include cattle, buffalo, pigs, sheep, goats and camelids[1][8]. Wild species such as deer and certain antelope can also become infected, and African buffalo are able to maintain infection within wildlife populations[6].
Importantly, FMD does not pose a significant risk to human health[2]. Occasional laboratory‑linked infections have been reported, but they result in mild symptoms and are unrelated to the common “hand, foot and mouth disease” of children[9]. Meat and dairy products from FMD‑infected animals are safe for human consumption after proper processing[9].
Animals Most Affected and Why They Are Susceptible
The severity of FMD varies by species, age and husbandry system. Cattle and pigs generally develop more severe clinical signs than small ruminants. Young animals (calves, lambs and piglets) are particularly vulnerable; mortality can exceed 20 % because the virus damages the heart muscle[10]. In adult animals, mortality is typically low (1–5 %), but morbidity approaches 100 % and leads to serious production losses[11].
The disease affects both intensive and extensive livestock systems. In intensive pig farms, the high density of animals facilitates airborne transmission. In grazing systems, animals are exposed through shared pastures and communal watering points. Small ruminants often display mild or subclinical signs, allowing them to act as silent spreaders. Wildlife, especially African buffalo, maintain FMDV in endemic regions and can reintroduce infection to domestic herds[6]. Because FMDV replicates rapidly and sheds before clinical signs appear, its control requires vigilant surveillance and strict movement management.
How FMD Spreads: Transmission Routes and Risk Factors
FMDV is present in all secretions and excretions of infected animals. Animals shed large quantities of virus in saliva, breath, milk, semen, urine and faeces[12]. Pigs, for example, can exhale enough virus to infect animals several kilometres downwind. Viral shedding begins up to four days before clinical signs appear[13], meaning apparently healthy animals can be highly infectious.
Direct contact is the most common transmission route: nose‑to‑nose contact, suckling and mating easily spread the virus. Indirect transmission is also efficient; FMDV can survive on contaminated equipment, vehicles, feed, water, hay or biologics, and on clothing, footwear and hands of people who move between farms[14]. Feeding improperly cooked meat or offal from infected animals can introduce the virus[15]. Aerosolised virus can travel on air currents, especially in cool, humid conditions, infecting animals kilometres away[16].
Recovery does not always end infectiousness. Recovered cattle or wildlife may become carriers and intermittently shed virus[7]. Because of this, movement of animals from endemic to disease‑free areas requires strict quarantine and testing. Human activities—trade, transport, tourism and even contaminated animal products—are the primary drivers of long‑distance spread.
Notifiable Disease and Reporting Requirements
FMD is a notifiable disease in most jurisdictions. For example, Ireland’s Department of Agriculture defines FMD as one of the most contagious livestock diseases and mandates immediate reporting of any suspected case[17]. Similar obligations apply across Europe under Commission Delegated Regulation (EU) 2020/687, which empowers authorities to order stamping‑out and movement restrictions[18]. Rapid reporting to veterinary authorities (and subsequently to WOAH through national focal points) triggers containment measures and helps protect trade partners from incursions. Producers and veterinarians should treat every vesicular lesion as suspicious and seek laboratory confirmation—delay can be devastating.
Clinical Signs and Economic Impact on Farms
Clinical Signs
The incubation period of FMD is 2–14 days[11]. Animals may become febrile, lethargic and anorexic before developing characteristic vesicles (blisters). These fluid‑filled blisters appear on the tongue, lips, inside the mouth, between the toes, above the hooves and on teats[19]. As blisters rupture, they leave painful ulcers that cause excess salivation, drooling and severe lameness, making animals reluctant to move or eat[20]. Blisters usually heal within a week, but secondary bacterial infections prolong recovery[21]. Other signs include fever, depression, weight loss and a drop in milk production[22]. In young animals, sudden death may occur from virus‑induced myocarditis (heart inflammation)[10].
Economic and Food‑Security Impact
Even when animals survive, FMD imposes severe economic costs. Lesions and fever cause dramatic reductions in milk yield (up to 80 %) and growth rates[22], delaying animals’ market readiness. Meat quality may be downgraded due to weight loss and stress. Farmers incur expenses for veterinary care and face extended withdrawal periods for milk and meat, delaying sale.
At a national level, FMD triggers immediate trade bans on livestock and animal products from affected regions, resulting in billions of dollars in lost exports. The FAO estimates that visible production losses and routine vaccination in endemic countries cost up to USD 28 billion per year[3]. Inclusion of trade disruptions and culling expenses pushes this figure far higher. For example, during the 2001 UK epidemic millions of animals were slaughtered, and losses exceeded £8 billion. FMD’s capacity to cripple food supply chains makes robust prevention strategies a global priority.
Diagnosis and Official Reporting Requirements
Diagnostic Methods
Because FMD resembles other vesicular diseases (vesicular stomatitis, swine vesicular disease, vesicular exanthema), laboratory confirmation is essential. Diagnosis typically involves:
Clinical examination – identification of vesicles, lameness and drooling.
Sample collection – vesicular fluid, epithelial tissue, blood or oropharyngeal swabs taken by a veterinarian.
Virus isolation and RT‑PCR – detection of FMDV genetic material and serotyping to identify the virus strain.
Serology – detection of antibodies to structural and non‑structural proteins to distinguish infected from vaccinated animals.
Samples must be submitted to accredited reference laboratories. Because FMD is notifiable, suspicion alone requires immediate report to veterinary authorities[17]. Rapid testing and prompt communication enable authorities to activate containment protocols, including quarantine, movement controls and, where necessary, stamping‑out.
Reporting and Communication
In Europe, special control measures under Regulation (EU) 2020/687 require stamping‑out infected and in‑contact herds and impose regional restrictions on movement of susceptible animals and animal products[23]. Member states must maintain contingency plans and collaborate with EU reference laboratories[24]. Similar requirements exist in other regions. Farmers should keep accurate herd records and contact their veterinarian at the first sign of a vesicular disease. Engaging promptly with authorities minimises outbreak size and shortens trade disruptions.
Prevention, Biosecurity and Vaccination Strategies
Preventing FMD requires an integrated approach combining farm‑level biosecurity, movement controls and vaccination. Key elements include:
Biosecurity and Movement Controls
Restrict access – Limit visitors and vehicles. Require disinfection of footwear, hands and equipment for anyone entering animal areas. Establish a single entry point with footbaths and hand sanitiser.
Quarantine new or returning animals – Keep incoming animals isolated for at least two weeks. Test for FMDV and only introduce animals to the herd if they are disease‑free.
Clean and disinfect – Regularly clean housing, feed troughs and transport vehicles. Use effective disinfectants proven to inactivate FMDV.
Manage feed and water – Protect feed and water sources from contamination by wildlife or feral animals. Do not feed raw meat or untreated animal products.
Control fomites – Avoid sharing equipment between farms. If equipment must be shared, clean and disinfect thoroughly before and after use.
- Educate staff – Train workers to recognise early signs of FMD and to follow biosecurity protocols. Keep written biosecurity plans accessible and review them regularly.
Vaccination Programmes
Vaccination is a crucial tool in endemic countries and regions at high risk. According to WOAH, vaccination programmes should meet several criteria: coverage of at least 80 % of the target population, rapid completion of campaigns, consideration of maternal immunity and correct administration of the vaccine[25]. The vaccines used must match the circulating serotypes and comply with WOAH potency and safety standards[26]. In Europe, an extensive antigen bank allows rapid formulation of vaccines if an outbreak occurs[23].
In some FMD‑free countries, vaccination is avoided because it complicates serological surveillance and trade. However, emergency or prophylactic vaccination may be deployed during outbreaks or when the risk of spread outweighs potential trade consequences. Authorities decide between ring vaccination (vaccinating animals in a zone around an outbreak) and mass vaccination based on outbreak severity and resource availability.
Stamping‑Out and Movement Restrictions
In FMD‑free regions, the primary control strategy remains stamping‑out: humane culling of infected and in‑contact animals, followed by thorough cleaning and disinfection. Movement of susceptible animals and animal products is restricted within defined protection and surveillance zones[23]. Quarantine and surveillance around outbreak sites continue until no new cases appear and serological surveys confirm virus absence. While costly and heartbreaking, stamping‑out is often the fastest way to eradicate FMD and regain disease‑free status.
There Is No Treatment
There is no antiviral treatment for FMD. Supportive care, such as providing soft feed and ensuring hydration, may ease suffering, but recovery depends on immune response. To prevent further spread, infected animals are usually culled rather than treated. Hence, prevention and rapid response are paramount.
Global Control Strategies: PCP‑FMD and International Cooperation
The Global FMD Control Strategy was launched by FAO and WOAH in 2012 to reduce the worldwide burden of FMD[27]. This strategy combines two complementary tools:
The Progressive Control Pathway for FMD (PCP‑FMD) – a stepwise framework guiding endemic countries through five stages, from initial assessment (Stage 0) to freedom (Stage 5). Each stage sets milestones for improving surveillance, vaccination, biosecurity and governance. The PCP‑FMD was developed by FAO and EuFMD and is endorsed by WOAH[28]. Countries progress at their own pace, with technical support from FAO and international partners.
The Performance of Veterinary Services (PVS) Pathway – WOAH’s tool for evaluating national veterinary services and aligning them with international standards. Strong veterinary services underpin FMD control by ensuring vaccine quality, effective surveillance and rapid response[29].
Regional programmes, such as the European Commission for the Control of FMD (EuFMD) and GF‑TADs regional roadmaps, facilitate cooperation and information sharing between neighbouring countries. The EU maintains one of the world’s largest antigen banks to provide rapid access to tailored vaccines[23]. International partners support endemic countries through training, risk assessment and resource mobilisation, with the goal of gradually eliminating FMD and preventing re‑introduction into disease‑free zones.
How Veterinarians and Farm Managers Can Reduce FMD Risk
FMD prevention is a shared responsibility. Veterinarians, producers and farm managers can minimise risk by:
Implementing strict biosecurity – as outlined above, controlling access, quarantining newcomers and maintaining disinfection routines.
Educating staff and neighbours – ensure all workers recognise vesicular diseases and understand the importance of early reporting. Share information with neighbouring farms to coordinate response.
Maintaining accurate records – track animal movements, vaccination dates, production metrics and health events. These records aid disease tracing and compensation claims.
Engaging in surveillance and testing – participate in national surveillance programmes, submit samples for serology and virus detection, and work with reference laboratories. Herd‑level monitoring helps identify silent circulation and measure vaccination efficacy.
Collaborating with authorities – develop emergency response plans with veterinary services, including culling and disposal procedures, communication protocols and compensation mechanisms. Compliance with official instructions is essential during outbreaks.
Planning vaccination strategically – if in an endemic region, follow approved vaccination schedules, ensure vaccines match circulating strains and avoid lapses that create immunity gaps.
Conclusion
FMD is a highly contagious viral disease that attacks the foundations of animal agriculture. Although not dangerous to humans, it causes fever, blisters, lameness and dramatic reductions in productivity in cloven‑hoofed livestock[1][30]. The economic impact runs into billions of dollars annually and can ruin livelihoods and food supply chains[3]. The virus spreads easily through direct and indirect contacts, aerosols and contaminated materials[14], and it is shed before clinical signs appear. Because there is no cure, prevention is the only defence.
What can you do? Recognise vesicular lesions quickly, report them immediately and follow official advice. Adopt stringent biosecurity practices on your farm, restrict movements and implement vaccination programmes where recommended. Support and participate in national and international control initiatives, such as the PCP‑FMD, to protect your herd and contribute to global eradication efforts. Together, veterinarians, farmers and policymakers can drive FMD toward history.
Disclaimer: This article is for educational purposes only and does not replace professional veterinary advice. Always consult your veterinarian or competent authority when dealing with potential cases of foot‑and‑mouth disease.
References & Hyperlinks
FAO. “Foot‑and‑mouth disease” – explanation of disease characteristics, host range, endemic regions and economic impact[31].
WOAH. “Foot‑and‑mouth disease – Transmission and spread” – description of virus serotypes, carriers, and transmission routes[5]【464571053765235†L293-L318】.
WOAH. Vaccination guidelines – criteria for coverage, timing and vaccine matching[32].
European Commission. “Foot‑and‑mouth disease – Control measures” – stamping‑out, movement restrictions and antigen banks[23].
Government of Ireland. “Foot and Mouth Disease” – notifiable disease status, species affected, zoonotic considerations and transmission[17][9][33].
GF‑TADs. “FMD” – global control strategy and PCP‑FMD framework[34].
WOAH. “Clinical signs” – clinical sign description and effects on production[35].
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https://www.fao.org/animal-health/animal-diseases/foot-and-mouth-disease/en
[5] [6] [7] [10] [11] [12] [13] [14] [15] [16] [19] [20] [21] [22] [25] [26] [30] [32] [35] Foot and mouth disease – WOAH – World Organisation for Animal Health
https://www.woah.org/en/disease/foot-and-mouth-disease/
[8] [9] [17] [33] Foot and Mouth Disease
[18] [23] [24] Foot-and-mouth disease – Food Safety – European Commission
