scholarly journals Lyapunov Stability Analysis of a Delayed Foot-and-Mouth Disease Model with Animal Vaccination

2020 ◽  
Vol 2020 ◽  
pp. 1-13
Author(s):  
Tinashe B. Gashirai ◽  
Senelani D. Hove-Musekwa ◽  
Steady Mushayabasa
Keyword(s):  
Disease Virus ◽  
Disease Model ◽  
Intervention Strategy ◽  
Ecological Factors ◽  
Foot And Mouth Disease ◽  
Mouth Disease ◽  
Sub Saharan Africa ◽  
Epidemic Dynamics ◽  
Mouth Disease Virus ◽  
Foot And Mouth

Foot-and-mouth disease virus remains one of the most important livestock diseases in sub-Saharan Africa and several Southeast Asian countries. Vaccination of livestock has been recognized as an important tool for the control of foot-and-mouth disease virus. However, this intervention strategy has some limitations. Generally, vaccine production is a complex multistep process which involves development, manufacturing, and delivery processes, and through this extensive process, some challenges such as poor vaccine storage often arise. More often, these challenges alter the validity of the vaccination. Foot-and-mouth disease virus epidemic dynamics have been extensively explored, but understanding the role of vaccination validity on virus endemicity is lacking. We present a time-delayed foot-and-mouth disease model that incorporates relevant biological and ecological factors, vaccination effects, and disease carriers. We determined the basic reproduction number and demonstrated that it is an important metric for persistence and extinction of the disease in the community. Numerical illustrations were utilised to support some of the analytical results.

scholarly journals Predicting antigenic sites on the foot-and-mouth disease virus capsid of the South African Territories types using virus neutralization data

2011 ◽  
Vol 92 (10) ◽  
pp. 2297-2309 ◽  
Author(s):  
F. F. Maree ◽  
B. Blignaut ◽  
J. J. Esterhuysen ◽  
T. A. P. de Beer ◽  
J. Theron ◽  
...  
Keyword(s):  
South African ◽  
Disease Virus ◽  
Foot And Mouth Disease ◽  
Mouth Disease ◽  
Sub Saharan Africa ◽  
Antigenic Sites ◽  
Mouth Disease Virus ◽  
Virus Serotype ◽  
Antigenic Properties ◽  
Foot And Mouth

Foot-and-mouth disease virus (FMDV) outer capsid proteins 1B, 1C and 1D contribute to the virus serotype distribution and antigenic variants that exist within each of the seven serotypes. This study presents phylogenetic, genetic and antigenic analyses of South African Territories (SAT) serotypes prevalent in sub-Saharan Africa. Here, we show that the high levels of genetic diversity in the P1-coding region within the SAT serotypes are reflected in the antigenic properties of these viruses and therefore have implications for the selection of vaccine strains that would provide the best vaccine match against emerging viruses. Interestingly, although SAT1 and SAT2 viruses displayed similar genetic variation within each serotype (32 % variable amino acids), antigenic disparity, as measured by r1-values, was less pronounced for SAT1 viruses compared with SAT2 viruses within our dataset, emphasizing the high antigenic variation within the SAT2 serotype. Furthermore, we combined amino acid variation and the r1-values with crystallographic structural data and were able to predict areas on the surface of the FMD virion as antigenically relevant. These sites were mostly consistent with antigenic sites previously determined for types A, O and C using mAbs and escape mutant studies. Our methodology offers a quick alternative to determine antigenic relevant sites for FMDV field strains.

scholarly journals Reconstructing Geographical Movements and Host Species Transitions of Foot-and-Mouth Disease Virus Serotype SAT 2

mBio ◽  
2013 ◽  
Vol 4 (5) ◽  
Author(s):  
Matthew D. Hall ◽  
Nick J. Knowles ◽  
Jemma Wadsworth ◽  
Andrew Rambaut ◽  
Mark E. J. Woolhouse
Keyword(s):  
Middle East ◽  
Disease Virus ◽  
North Africa ◽  
Host Species ◽  
Foot And Mouth Disease ◽  
Mouth Disease ◽  
Sub Saharan Africa ◽  
Mouth Disease Virus ◽  
Foot And Mouth ◽  
Sub Saharan

ABSTRACT Of the three foot-and-mouth-disease virus SAT serotypes mainly confined to sub-Saharan Africa, SAT 2 is the strain most often recorded in domestic animals and has caused outbreaks in North Africa and the Middle East six times in the last 25 years, with three apparently separate events occurring in 2012. This study updates the picture of SAT 2 phylogenetics by using all available sequences for the VP1 section of the genome available at the time of writing and uses phylogeographic methods to trace the origin of all outbreaks occurring north of the Sahara since 1990 and identify patterns of spread among countries of endemicity. Transitions between different host species are also enumerated. Outbreaks in North Africa appear to have origins in countries immediately south of the Sahara, whereas those in the Middle East are more often from East Africa. The results of the analysis of spread within sub-Saharan Africa are consistent with it being driven by relatively short-distance movements of animals across national borders, and the analysis of host species transitions supports the role of the African buffalo (Syncerus caffer) as an important natural reservoir. IMPORTANCE Foot-and-mouth disease virus is a livestock pathogen of major economic importance, with seven distinct serotypes occurring globally. The SAT 2 serotype, endemic in sub-Saharan Africa, has caused a number of outbreaks in North Africa and the Middle East during the last decades, including three separate incidents in 2012. A comprehensive analysis of all available RNA sequences for SAT 2 has not been published for some years. In this work, we performed this analysis using all previously published sequences and 49 newly determined examples. We also used phylogenetic methods to infer the source country for all outbreaks occurring outside sub-Saharan Africa since 1990 and to reconstruct the spread of viral lineages between countries where it is endemic and movements between different host species.

High resolution surface structure of foot-and-mouth disease virus

1978 ◽  
Vol 36 (2) ◽  
pp. 376-377
Author(s):  
S. S. Breese ◽  
H. L. Bachrach
Keyword(s):  
Electron Microscopy ◽  
High Resolution ◽  
Surface Structure ◽  
Disease Virus ◽  
Potassium Phosphate ◽  
Foot And Mouth Disease ◽  
Mouth Disease ◽  
Physical Measurements ◽  
Mouth Disease Virus ◽  
Foot And Mouth

Models for the structure of foot-and-mouth disease virus (FMDV) have been proposed from chemical and physical measurements (Brown, et al., 1970; Talbot and Brown, 1972; Strohmaier and Adam, 1976) and from rotational image-enhancement electron microscopy (Breese, et al., 1965). In this report we examine the surface structure of FMDV particles by high resolution electron microscopy and compare it with that of particles in which the outermost capsid protein VP3 (ca. 30, 000 daltons) has been split into smaller segments, two of which VP3a and VP3b have molecular weights of about 15, 000 daltons (Bachrach, et al., 1975).Highly purified and concentrated type A12, strain 119 FMDV (5 mg/ml) was prepared as previously described (Bachrach, et al., 1964) and stored at 4°C in 0. 2 M KC1-0. 5 M potassium phosphate buffer at pH 7. 5. For electron microscopy, 1. 0 ml samples of purified virus and trypsin-treated virus were dialyzed at 4°C against 0. 2 M NH4OAC at pH 7. 3, deposited onto carbonized formvar-coated copper screens and stained with phosphotungstic acid, pH 7. 3.

Sign in / Sign up

Export Citation Format

Share Document