Editorial: FMD Research: Bridging the Gaps With Novel Tools

1 Instituto de Virología e Innovaciones Tecnológicas (IVIT), Centro de Investigaciones en Ciencias Veterinarias y Agronómicas (CICVyA), Instituto Nacional de Tecnología Agropecuaria (INTA)Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina, 2 Australian Centre for Disease Preparedness (Formerly Australian Animal Health Laboratory), Commonwealth Scientific and Industrial Research Organisation (CSIRO)-Health and Biosecurity, Geelong, VIC, Australia, 3 Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Greenport, NY, United States


Editorial on the Research Topic FMD Research: Bridging the Gaps With Novel Tools
Foot and mouth disease (FMD) remains a major threat for livestock industries, affecting large numbers of cloven-hoofed animal species worldwide with an estimated annual global economic loss of between US$6.5 and 21 billion and ∼US$ 5 billion related to production losses and vaccination alone (1). The devastating effects of FMD affects all countries around the world impacting from smallholders' farms in low-income countries suffering reduced productivity (2), to middle-to-high income countries affected by the cost of prevention, surveillance, and control measures in domestic species as well as the severe restrictions imposed on international trade (3).
FMD's etiological agent is a small non-enveloped positive sense single-stranded RNA virus (FMDV) belonging to the Picornaviridae family, genus Aphthovirus (4). Considered as one of the most infectious amongst human or animal disease agents known, the virus is recognized for its high antigenic variability and efficient transmission among a wide range of susceptible animal species (5). Although progress in the global control of FMD is ongoing and supported by international organizations such as the World Organisation for Animal Health (OIE) and United Nations Food and Agriculture Organisation, the disease is still endemic in many parts of the world, circulating in over 75% of the global livestock population (2).
Scientists working on FMD research around the world are networking through the Global Foot and Mouth Disease Research Alliance (GFRA-https://www.ars.usda.gov/gfra/). The GFRA continually assesses research gaps and priorities, shares the latest scientific advances, and enables and promotes collaborations and networking among the different laboratories conducting FMD research worldwide. This Research Topic focuses on recent studies that address FMD knowledge gaps, comprising 24 original manuscripts covering priority areas such as diagnostics, field surveillance, evolution, molecular epidemiology, immunopathogenesis, vaccine development, immunology, and antiviral therapy.
Strategies for FMD control vary between regions depending on their epidemiological situation. To manage the risk, it is essential that governments, farmers, veterinarians, and industries engage in significant surveillance, prevention, control, and preparedness programs.
Field surveillance is a critical component of any disease control program. Singanallur et al. demonstrated circulation of FMDV in goat populations in Lao, using two serological tests on a set of samples collected from several provinces and analyze different factors related to seropositivity. Using a different strategy, Ularamu et al. collected tissue samples from 27 outbreaks of FMD in different states of Nigeria to gain more knowledge on FMDV circulation in this country. FMDV isolates obtained were serotyped and further characterized by VP1 sequencing and phylogenetic analysis. Velazquez-Salinas et al. provided a collection of VP (viral protein) 1 and P1 (complete capsid coding region) protein sequences from 29 different districts in Uganda, which combined with geographic information, may be used to perform phylogenetic analyses and antigenic characterization of the FMDV variants circulating in this region. Finally, aiming to improve the serotype-independent FMDV detection, Mishu et al. analyzed the comparative evolutionary divergence of VP2 and VP1 nucleotide sequences to determine the level of conservation in VP2 at different hierarchical levels of three FMDV serotypes (O, A, and Asia1) currently circulating in Asia.
For many years, FMD diagnostic tests have evolved to analyze different aspects of the disease and vaccination, however many of them still need to be assessed and validated for both sensitivity and specificity. Gray et al. analyzed the comparative performance for FMDV isolation between a highly sensitive primary cell culture (BTY) and two continuous cell lines derived from goat (ZZ-R 127) and swine (LFBK-αVβ6). Also, new approaches aim to improve the efficacy of the surveillance programs. This wide collection of original manuscripts undoubtedly contributes to the understanding of the disease and the development of suitable tools and methods for FMD control. However, there are still research gaps that need to be fulfilled to provide the knowledge and tools required to advance the progressive global control of FMD. It is noteworthy that no research papers related to vaccine selection and protection against heterologous FMDV strains were submitted. This subject, together with basic immunity, constitute one of the areas where there is still room for improvement. More work is needed to expand our understanding of vaccine cross-protection, especially in heterologous systems, information that is critical to select suitable vaccines to respond to FMD outbreaks and in the designing of antigen and vaccine banks.
The eradication of FMD is complex and must involve the integration of new approaches as control strategies. Successful health management policies to contain and eradicate FMD must combine diverse intervention and outbreak mitigation approaches. In this context, GFRA will continue promoting multidisciplinary scientific research among its partners aiming to develop comprehensive responses to the numerous challenges still posed by FMD at the global scale.