A Comprehensive Review of the Immunological Response against Foot-and-Mouth Disease Virus Infection and Its Evasion Mechanisms

Intradermal Inoculation of Inactivated Foot-and-Mouth Disease Vaccine Induced Effective Immune Responses Comparable to Conventional Intramuscular Injection in Pigs

All pigs in the Republic of Korea are given the foot-and-mouth disease virus (FMDV) vaccine intramuscularly (IM) as part of the country's vaccination policy. However, the IM administration of the FMDV vaccine to pig results in residual vaccine components in the muscle and undesirable changes in muscle and soft tissues, causing economic losses in swine production. In this study, we evaluated whether intradermal (ID) vaccination could be proposed as an alternative to IM administration. ID vaccination (0.2 mL on each side of the neck muscle) and IM vaccination (2 mL on each side of the neck muscle) were performed twice, separated by 14 days, using a commercial FMD vaccine in specific-pathogen-free pigs. We observed growth performance, gross and microscopic lesions at the inoculation site, FMDV-specific antibodies, and neutralizing antibodies for 35 days after vaccination. Side effects on the skin grossly appeared following ID administration, but most were reduced within two weeks. All ID-vaccinated pigs showed inflammatory lesions limited to the dermis, but IM-vaccinated pigs had abnormal undesirable changes and pus in the muscle. ID-vaccinated pigs performed comparably to IM-vaccinated pigs in terms of growth, FMD virus-specific antibodies, protection capability against FMDV, and T-cell induction. This study demonstrated that the ID inoculation of the inactivated FMD vaccine induced immune responses comparable to an IM injection at 1/10 of the inoculation dose and that the inoculation lesion was limited to the dermis, effectively protecting against the formation of abnormal undesirable changes in muscle and soft tissues.

A review of foot-and-mouth disease in Ethiopia: epidemiological aspects, economic implications, and control strategies

Foot-and-mouth disease (FMD) is a contagious viral disease that affects the livelihoods and productivity of livestock farmers in endemic regions. It can infect various domestic and wild animals with cloven hooves and is caused by a virus belonging to the genus Aphthovirus and family Picornaviridae, which has seven different serotypes: A, O, C, SAT1, SAT2, SAT3, and Asia-1. This paper aims to provide a comprehensive overview of the molecular epidemiology, economic impact, diagnosis, and control measures of FMD in Ethiopia in comparison with the global situation. The genetic and antigenic diversity of FMD viruses requires a thorough understanding for developing and applying effective control strategies in endemic areas. FMD has direct and indirect economic consequences on animal production. In Ethiopia, FMD outbreaks have led to millions of USD losses due to the restriction or rejection of livestock products in the international market. Therefore, in endemic areas, disease control depends on vaccinations to prevent animals from developing clinical disease. However, in Ethiopia, due to the presence of diverse antigenic serotypes of FMD viruses, regular and extensive molecular investigation of new field isolates is necessary to perform vaccine-matching studies to evaluate the protective potential of the vaccine strain in the country.

Effect of Cattle-Specific Diseases on Carcass Inspection and Meat Quality

There are severe cattle-specific viral (foot and mouth, vesicular stomatitis, rinderpest, rift valley fever, malignant catarrhal fever, lumpy skin, rabies, bovine leukosis, bovine viral diarrhea, and bovine spongiform encephalopathy), bacterial (tuberculosis, black quarter, botulism, malignant oedema, leptospirosis, brucellosis, anthrax, hemogenic septicemia, actinomycosis, actinobacillosis, mastitis, and metritis), parasitic (lungworm, fasciolosis, cysticercosis, hydatid disease, and onchocercosis), and protozoal (trypanosomiasis, theileriosis, anaplasmosis, babesiosis, and sarcosporidiosis) diseases that affect the carcass judgment and meat quality. These diseases adversely affect cattle health, welfare, and red meat production. This chapter aims to describe the etiology, mode of transmission, ante-mortem and post-mortem findings, carcass and meat quality judgment, and differential diagnosis of these diseases.

Antiviral Effect of Manganese against Foot-and-Mouth Disease Virus Both in PK15 Cells and Mice

Foot-and-mouth disease (FMD) is an acute contagious disease of cloven-hoofed animals such as cattle, pigs, and sheep. Current emergency FMD vaccines are of limited use for early protection because their protective effect starts 7 days after vaccination. Therefore, antiviral drugs or additives are used to rapidly stop the spread of the virus during FMD outbreaks. Manganese (Mn²⁺) was recently found to be an important substance necessary for the host to protect against DNA viruses. However, its antiviral effect against RNA viruses remains unknown. In this study, we found that Mn²⁺ has antiviral effects on the FMD virus (FMDV) both in PK15 cells and mice. The inhibitory effect of Mn²⁺ on FMDV involves NF-κB activation and up-regulation of interferon-stimulated genes. Animal experiments showed that Mn²⁺ can be highly effective in protecting C57BL/6N mice from being infected with FMDV. Overall, we suggest Mn²⁺ as an effective antiviral additive for controlling FMDV infection.

Advances in the differential molecular diagnosis of vesicular disease pathogens in swine

Foot-and-mouth disease virus (FMDV), Senecavirus A (SVA) and swine vesicular disease virus (SVDV) are members of the family Picornaviridae, which can cause similar symptoms - vesicular lesions in the tissues of the mouth, nose, feet, skin and mucous membrane of animals. Rapid and accurate diagnosis of these viruses allows for control measures to prevent the spread of these diseases. Reverse transcription-polymerase chain reaction (RT-PCR) and real-time RT-PCR are traditional and reliable methods for pathogen detection, while their amplification reaction requires a thermocycler. Isothermal amplification methods including loop-mediated isothermal amplification and recombinase polymerase amplification developed in recent years are simple, rapid and do not require specialized equipment, allowing for point of care diagnostics. Luminex technology allows for simultaneous detection of multiple pathogens. CRISPR-Cas diagnostic systems also emerging nucleic acid detection technologies which are very sensitivity and specificity. In this paper, various nucleic acid detection methods aimed at vesicular disease pathogens in swine (including FMDV, SVA and SVDV) are summarized.

Nanovaccines against Animal Pathogens: The Latest Findings

Nowadays, safe and efficacious vaccines represent powerful and cost-effective tools for global health and economic growth. In the veterinary field, these are undoubtedly key tools for improving productivity and fighting zoonoses. However, cases of persistent infections, rapidly evolving pathogens having high variability or emerging/re-emerging pathogens for which no effective vaccines have been developed point out the continuing need for new vaccine alternatives to control outbreaks. Most licensed vaccines have been successfully used for many years now; however, they have intrinsic limitations, such as variable efficacy, adverse effects, and some shortcomings. More effective adjuvants and novel delivery systems may foster real vaccine effectiveness and timely implementation. Emerging vaccine technologies involving nanoparticles such as self-assembling proteins, virus-like particles, liposomes, virosomes, and polymeric nanoparticles offer novel, safe, and high-potential approaches to address many vaccine development-related challenges. Nanotechnology is accelerating the evolution of vaccines because nanomaterials having encapsulation ability and very advantageous properties due to their size and surface area serve as effective vehicles for antigen delivery and immunostimulatory agents. This review discusses the requirements for an effective, broad-coverage-elicited immune response, the main nanoplatforms for producing it, and the latest nanovaccine applications for fighting animal pathogens.