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Foot-and-Mouth Disease (FMD), as a major global animal disease, affects millions of animals worldwide and remains the main sanitary barrier to the international and national trade of animals and animal products. Inactivated vaccination is the most effective measure for prevention of FMD at present, but fail to induce long-term protection and content new requires for production of FMD vaccines. As a number of Researchers hope to obtain satisfactory novel vaccines by new bio-technology, novel vaccines have been studied for more than thirty years. Here reviews the latest research progress of new vaccines, summarizes some importance and raises several suggestions for the future of FMD vaccine.

Background Hepatitis A virus is the causative agent of type A viral hepatitis, which causes occasional acute hepatitis. Nevertheless, little information about synonymous codon usage pattern of HAV genome in the process of its evolution is available. In this study, the key genetic determinants of codon usage in HAV were examined. Results The overall extent of codon usage bias in HAV is high in Picornaviridae. And the patterns of synonymous codon usage are quite different in HAV genomes from different location. The base composition is closely correlated with codon usage bias. Furthermore, the most important determinant that results in such a high codon bias in HAV is mutation pressure rather than natural selection. Conclusions HAV presents a higher codon usage bias than other members of Picornaviridae. Compositional constraint is a significant element that influences the variation of synonymous codon usage in HAV genome. Besides, mutation pressure is supposed to be the major factor shaping the hyperendemic codon usage pattern of HAV.

Backgroud Foot-and-mouth disease (FMD) is one of the most contagious of all artiodactyl animal diseases, and its infection has an obvious ability to spread over long distances and to contribute to epidemics in FMD-free areas. A highly sensitive and specific method is required to detect FMDV. In this study, we evaluated the usefulness of a bio-barcode assay (BCA) technique for detecting clinical samples of FMDV. Methods Highly sensitive gold nanopariticle (GNP) improved immuno-PCR (GNP-IPCR) which derived from the bio-barcode assay (BCA) was designed for the detection of FMDV. The target viral particles were captured by a polyclonal antibody coated on ELISA microplate, followed by adding GNP which was dually modified with oligonucleotides and a FMDV specific monoclonal antibody (MAb) 1D11 to form a sandwiched immune complex. After the formation of immuno-complex, the signal DNA was released by heating, and consequently characterized by PCR and real time PCR. Results The detection limit of GNP-PCR could reach to 10 fg/ml purified FMDV particles, and the assay can detect clinical samples of FMDV with highly sensitivity, while detect limit of conventional ELISA is 100 ng/ml in this study. Conclusion GNP-IPCR may provide a highly sensitive method for the detection of FMDV.

Background FMD is one of the major causes of economic loss of cloven-hoofed animals in the world today. The assessment of dominant genotype/lineage and prevalent trends and confirmation the presence of infection or vaccination not only provides scientific basis and first-hand information for appropriate control measure but also for disease eradication and regaining FMD free status following an outbreak. Although different biological and serological approaches are still applied to study this disease, ELISA test based on the distinct format, antigen type and specific antibody reinforce its predominance in different research areas of FMD, and this may replace the traditional methods in the near future. This review gives comprehensive insight on ELISA currently available for typing, antigenic analysis, vaccination status differentiation and surveillance vaccine purity and content at all stages of manufacture in FMDV. Besides, some viewpoint about the recent advances and trends of ELISA reagent for FMD are described here. Methods More than 100 studies regarding ELISA method available for FMD diagnosis, antigenic analysis and monitor were thoroughly reviewed. We investigated previous sagacious results of these tests on their sensitivity, specificity. Results We found that in all ELISA formats for FMD, antibody-trapping and competitive ELISAs have high specificity and RT-PCR (oligoprobing) ELISA has extra sensitivity. A panel of monoclonal antibodies to different sites or monoclonal antibody in combination of antiserum is the most suitable combination of antibodies in ELISA for FMD. Even though from its beginning, 3ABC is proven to be best performance in many studies, no single NSP can differentiate infected from vaccinated animals with complete confidence. Meanwhile, recombinant antigens and peptide derived from FMDV NPs, and NSPs have been developed for use as an alternative to the inactivated virus antigen for security. Conclusions There is a need of target protein, which accurately determines the susceptible animal status based on the simple, fast and reliable routine laboratory test. A further alternative based on virus-like particle (VLP, also called empty capsids) in combination of high throughput antibody technique (Phage antibody library/antibody microarray) may be the powerful ELISA diagnostic reagents in future.

Foot-and-mouth disease (FMD) is one of most contagious animal diseases. It affects millions of cloven-hoofed animals and causes huge economic losses in many countries of the world. There are seven serotypes of which three (O, A and Asia 1) are endemic in China. Efficient control of FMD in China is crucial for the prevention and control of FMD in Asia and throughout the world. For the control of FMD, a powerful veterinary administration, a well-trained veterinary staff, a system of rapid and accurate diagnostic procedures and, in many countries, compulsory vaccination of susceptible animals are indispensable. This article strives to outline the Chinese animal disease control and prevention system, in particular for FMD, with the emphasis on diagnostic procedures applied in Chinese laboratories. In addition, new technologies for FMD diagnosis, which are currently in the phase of development or in the process of validation in Chinese laboratories, are described, such as lateral flow devices (LFD), Mab-based ELISAs, reverse transcription loop-mediated isothermal amplification (RT-LAMP) and gold nanopariticle immuno-PCR (GNP-IPCR).

Background Poliovirus, the causative agent of poliomyelitis, is a human enterovirus and a member of the family of Picornaviridae and among the most rapidly evolving viruses known. Analysis of codon usage can reveal much about the molecular evolution of the viruses. However, little information about synonymous codon usage pattern of polioviruses genome has been acquired to date. Methods The relative synonymous codon usage (RSCU) values, effective number of codon (ENC) values, nucleotide contents and dinucleotides were investigated and a comparative analysis of codon usage pattern for open reading frames (ORFs) among 48 polioviruses isolates including 31 of genotype 1, 13 of genotype 2 and 4 of genotype 3. Results The result shows that the overall extent of codon usage bias in poliovirus samples is low (mean ENC = 53.754 > 40). The general correlation between base composition and codon usage bias suggests that mutational pressure rather than natural selection is the main factor that determines the codon usage bias in those polioviruses. Depending on the RSCU data, it was found that there was a significant variation in bias of codon usage among three genotypes. Geographic factor also has some effect on the codon usage pattern (exists in the genotype-1 of polioviruses). No significant effect in gene length or vaccine derived polioviruses (DVPVs), wild viruses and live attenuated virus was observed on the variations of synonymous codon usage in the virus genes. The relative abundance of dinucleotide (CpG) in the ORFs of polioviruses are far below expected values especially in DVPVs and attenuated virus of polioviruses genotype 1. Conclusion The information from this study may not only have theoretical value in understanding poliovirus evolution, especially for DVPVs genotype 1, but also have potential value for the development of poliovirus vaccines.