Foot-and-Mouth Disease Diversity Complex and Effective Management of the Disease

IntroductionFoot-and-Mouth Disease (FMD) is the most devastating disease of ungulates, causing huge economic losses in the livestock sector worldwide. Foot-and-Mouth Disease virus (FMDV), the aetiological agent of this disease, belongs to the family Picornaviridae of the genus Aphthovirus. The virus is known to be one of the most fearful viral pathogens of animals due to its high contagiousness, near 100% morbidity, close to 50% mortality in young animals (Sard, 1978) among all ungulates (domestic and wild) (Bachrach, 1968; Carrillo et al., 2005); global distribution; and severe economic impacts (Alexandersen et al., 2003; Sakamoto et al., 2002), especially among smallholder farmers, the highest holders of domestic ungulates in many African countries where FMD is endemic (Sopeju et al., 2025; Reference).Historically, in the late nineteenth century (1898 to be precise), Loeffler and Frosch showed that FMD is caused by an agent smaller than bacteria—a submicroscopic, filterable, transmissible agent. This agent, now known as FMDV, was the first virus of vertebrates to be discovered, and in 1922, Vallée and Carré reported the existence of serotypes O and A as being immunological types of FMDV by using cross-immunity tests in cattle, designated by their areas of origin: O (Oise, a department in northern France) and A (Allemagne—Germany), respectively (Vallée & Carré, 1922; Knowles, 1990). A century has passed, but the impacts of the disease have not left us, as many countries still remain endemic to the disease, making it the oldest known animal viral disease of global economic importance to date. This indicates that there is a complex that must be understudied and well understood if significant progress with the control of FMD is to be made at the end of another century.There have been several studies that document the diversity of FMD, ranging from the diversity of the FMD virus (Diab et al., 2025; WOAH/FAO, 2026) and serotypes (Wungak et al., 2017; Sopeju et al., 2026), the extremely wide host range (close to 70 animal species) (Jara et al., 2019; Hedger, 1981), various ecological drivers (Nardo et al., 2021; Alkhamis et al., 2025), and complicated local and regional control measures (Maree et al., 2014; Ularamu et al., 2020; Kusumastuti et al., 2024) and how they influence the disease spread and maintenance in the face of the current control measures, which is summarily termed “FMD Diversity Complex” in this paper. FMDV diversity is complex and has strong implications for disease control, particularly regarding virus detection, vaccine design, and the implementation of control measures. Some of these critical implications include lack of cross-protection between serotypes (Jamal & Belsham, 2013); limited vaccination effectiveness, requiring genetically matched vaccines (Ali et al., 2024); and substantial economic losses due to trade restrictions (Zewdie et al., 2023) that are enacted to prevent the introduction of new strains into a region where they were not originally found.Therefore, this review seeks to put all this information together in a simple, coherent way to increase comprehension of the complexity and present the significance of those contributions to livestock stakeholders. To that end, it may drive effective control through informed policymaking and stakeholders' application of the concept of the FMDV diversity complex. Furthermore, information in this review can be used to create awareness among the public, professionals, and policymakers; design a customized effective control plan locally, nationally, and regionally; and help farmworkers who detect FMD at the earliest possible time make informed decisions about the disease control, specifically with the choice of vaccine and application of other suggested control measures. It will also present various control measures that are practical, which, if combined together, may be relevant to the control plan for FMD globally.