Preparation of Foot and Mouth Disease trivalent vaccine type A, O, SAT2 and determination of the Guinea pig protective dose 50 (GPPD50)

Aim: The present study was aimed to investigate the epidemic situation of foot-and-mouth disease (FMD) in Egypt from 2016 to 2018 based on the detection of FMD virus (FMDV) in carrier or previously infected animals, by determination of antibodies against non-structural protein (NSP), implementation a pilot study on circulating FMDV serotypes and assure the efficacy of locally produced inactivated trivalent vaccine. Materials and Methods: A total of 1500 sera were collected from apparent healthy vaccinated cattle and buffaloes from three Egyptian geographical sectors, representing ten governorates. Determination of FMD antibodies against NSP was carried out using 3ABC enzyme-linked immunosorbent assay (ELISA) test. Serotyping of the circulating FMDV and assure the vaccine efficacy was performed using solid-phase competitive ELISA. Results: The 3ABC ELISA test revealed 26.4% and 23.7% positive for FMDV-NSP antibodies in cattle and buffalo sera, respectively. The highest positivity was in Delta Sector among both cattle 42.3% and buffaloes 28.8%. Serotyping of FMDV-positive NSP sera in El-Qalyubia Governorate for the circulating FMDV serotypes O, A, and Southern African Territories (SAT) 2 was 52.2%, 17.4%, and 30.4% in cattle and 31.8%, 27.3%, and 40.9% in buffaloes, respectively. The overall protection level due to the vaccination program was 62.1 and 60.9% in cattle and buffaloes, respectively, while the protective level of the FMDV serotypes O, A, and SAT2 included in the inactivated trivalent vaccine was 73.9, 84.6, and 63.8% in cattle and 72.3, 82.3, and 63.5% in buffaloes, respectively. Conclusion: The present study recommended full determination for the immunogenic relationship between the vaccine strains and the field strains to attain maximum protection against the circulating viruses.

Download Full-text

Effect of data quality on estimates of farm infectiousness trends in the UK 2001 foot-and-mouth disease epidemic

Journal of The Royal Society Interface ◽

10.1098/rsif.2006.0178 ◽

2006 ◽

Vol 4 (13) ◽

pp. 235-241 ◽

Cited By ~ 13

Author(s):

Nicholas J Savill ◽

Darren J Shaw ◽

Rob Deardon ◽

Michael J Tildesley ◽

Matthew J Keeling ◽

...

Keyword(s):

Mathematical Models ◽

Data Quality ◽

Foot And Mouth Disease ◽

Mouth Disease ◽

Inaccurate Data ◽

Foot And Mouth ◽

The Uk ◽

Parameter Values

Most of the mathematical models that were developed to study the UK 2001 foot-and-mouth disease epidemic assumed that the infectiousness of infected premises was constant over their infectious periods. However, there is some controversy over whether this assumption is appropriate. Uncertainty about which farm infected which in 2001 means that the only method to determine if there were trends in farm infectiousness is the fitting of mechanistic mathematical models to the epidemic data. The parameter values that are estimated using this technique, however, may be influenced by missing and inaccurate data. In particular to the UK 2001 epidemic, this includes unreported infectives, inaccurate farm infection dates and unknown farm latent periods. Here, we show that such data degradation prevents successful determination of trends in farm infectiousness.

Download Full-text

Extensive antigenic and genetic variation among foot-and-mouth disease type A viruses isolated from the 1994 and 1995 foci in São Paulo, Brazil

Veterinary Microbiology ◽

10.1016/s0378-1135(01)00451-5 ◽

2002 ◽

Vol 84 (1-2) ◽

pp. 15-27 ◽

Cited By ~ 19

Author(s):

J.P Araújo ◽

H.J Montassier ◽

A.A Pinto

Keyword(s):

Genetic Variation ◽

Foot And Mouth Disease ◽

Type A ◽

Sao Paulo ◽

Disease Type ◽

Mouth Disease ◽

São Paulo ◽

Foot And Mouth

Download Full-text

Novel antibody binding determinants on the capsid surface of serotype O foot-and-mouth disease virus

Journal of General Virology ◽

10.1099/vir.0.060939-0 ◽

2014 ◽

Vol 95 (5) ◽

pp. 1104-1116 ◽

Cited By ~ 19

Author(s):

Amin S. Asfor ◽

Sasmita Upadhyaya ◽

Nick J. Knowles ◽

Donald P. King ◽

David J. Paton ◽

...

Keyword(s):

Amino Acid ◽

Guinea Pig ◽

Foot And Mouth Disease ◽

Mouth Disease ◽

Amino Acid Residues ◽

Serotype O ◽

Antigenic Sites ◽

Mouth Disease Virus ◽

Foot And Mouth ◽

The Impact

Five neutralizing antigenic sites have been described for serotype O foot-and-mouth disease viruses (FMDV) based on monoclonal antibody (mAb) escape mutant studies. However, a mutant virus selected to escape neutralization of mAb binding at all five sites was previously shown to confer complete cross-protection with the parental virus in guinea pig challenge studies, suggesting that amino acid residues outside the mAb binding sites contribute to antibody-mediated in vivo neutralization of FMDV. Comparison of the ability of bovine antisera to neutralize a panel of serotype O FMDV identified three novel putative sites at VP2-74, VP2-191 and VP3-85, where amino acid substitutions correlated with changes in sero-reactivity. The impact of these positions was tested using site-directed mutagenesis to effect substitutions at critical amino acid residues within an infectious copy of FMDV O1 Kaufbeuren (O1K). Recovered viruses containing additional mutations at VP2-74 and VP2-191 exhibited greater resistance to neutralization with both O1K guinea pig and O BFS bovine antisera than a virus that was engineered to include only mutations at the five known antigenic sites. The changes at VP2-74 and VP3-85 are adjacent to critical amino acids that define antigenic sites 2 and 4, respectively. However VP2-191 (17 Å away from VP2-72), located at the threefold axis and more distant from previously identified antigenic sites, exhibited the most profound effect. These findings extend our knowledge of the surface features of the FMDV capsid known to elicit neutralizing antibodies, and will improve our strategies for vaccine strain selection and rational vaccine design.

Download Full-text