scholarly journals A Five-Year Retrospective Study of Foot-and-Mouth Disease Outbreaks in Southern Africa, 2014 to 2018

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Elliot Mpolokang Fana ◽  
Sununguko Wata Mpoloka ◽  
Melvin Leteane ◽  
LaToya Seoke ◽  
Kelebogile Masoba ◽  
...  

Foot-and-mouth disease (FMD) virus (FMDv), like other ribonucleic acid (RNA) genome viruses, has a tendency to mutate rapidly. As such, available vaccines may not confer enough cross-protection against incursion of new lineages and sublineages. This paper is a retrospective study to determine the topotypes/lineages that caused previous FMD outbreaks in 6 southern African countries and the efficacy of the current vaccines to protect cattle against them. A total of 453 bovine epithelial tissue samples from 33 FMD outbreaks that occurred in these countries from 2014 to 2018 were investigated for the presence of FMDv. The genetic diversity of the identified Southern African Type (SAT)-FMD viruses was determined by comparing sequences from outbreaks and historical prototype sequences. Of the 453 samples investigated, 176 were positive for four FMDv serotypes. Out of the 176 FMD positive cases there were 105 SAT2 samples, 32 SAT1 samples, 21 SAT3 samples, and 18 serotype O samples. Phylogenetic analysis grouped the SATs VP1 gene sequences into previously observed topotypes in southern Africa. SAT1 viruses were from topotypes I and III, SAT2 viruses belonged to topotypes I, II, III, and IV, and SAT3 viruses were of topotypes I and II. Vaccine matching studies on the field FMDv isolates produced r1-values greater than or equal to 0.3 for the three SAT serotypes. This suggests that there is no significant antigenic difference between current SAT FMD vaccine strains and the circulating SAT serotypes. Therefore, the vaccines are still fit-purpose for the control FMD in the region. The study did not identify incursion of any new lineages/topotypes of FMD into the sampled southern African countries.

1953 ◽  
Vol 51 (4) ◽  
pp. 546-558 ◽  
Author(s):  
W. M. Henderson ◽  
Ian A. Galloway

In three cattle vaccination experiments, with three strains of the virus of foot-and-mouth disease, it was shown that virus passaged in culture in cattle tongue epithelial tissue was as effective an antigen as virus passaged in cattle.With two virus strains, the virus content of the culture at the peak of infectivity was about the same as that of vesicle epithelium from the tongues of reacting cattle. Variable and less satisfactory results were obtained with the third strain, but one culture passage yielded tissue of sufficiently high virus content for the preparation of vaccine of adequate potency.No modification in the antigenic behaviour of the strains was detected as a result of passage in culture.It is a pleasure to acknowledge the technical assistance given by Mr W. J. Brownsea.


2015 ◽  
Vol 64 (3) ◽  
pp. 849-860 ◽  
Author(s):  
G. Govindaraj ◽  
B. Ganeshkumar ◽  
K. R. Nethrayini ◽  
R. Shalini ◽  
V. Balamurugan ◽  
...  

1954 ◽  
Vol 52 (1) ◽  
pp. 87-99 ◽  
Author(s):  
J. B. Brooksby ◽  
Ella Wardle

A technique is presented for the titration of the virus of foot-and-mouth disease in culture in surviving epithelial tissue from the tongues of cattle. The cultures are incubated in cups on Perspex plates, and the detection of virus multiplication is by a complement-fixation test made on the culture in each cup.On the basis of comparative titrations in culture and in cattle, the method has been found to be as sensitive for the detection of virus as the titration by intradermal inoculation of the tongue of cattle. The method can also be applied in the detection of antibody in neutralization tests.We wish to record our thanks to Messrs E. Scoates and P. Mitchell for their technical assistance, and to Messrs H. M. Smith, R. H. Compton and R. L. Jackson for their part in the design and fabrication of various bottle rotators, plate shakers, Perspex lids and the inoculating box.


2017 ◽  
Vol 91 (22) ◽  
Author(s):  
Michael Puckette ◽  
Benjamin A. Clark ◽  
Justin D. Smith ◽  
Traci Turecek ◽  
Erica Martel ◽  
...  

ABSTRACT The foot-and-mouth disease virus (FMDV) afflicts livestock in more than 80 countries, limiting food production and global trade. Production of foot-and-mouth disease (FMD) vaccines requires cytosolic expression of the FMDV 3C protease to cleave the P1 polyprotein into mature capsid proteins, but the FMDV 3C protease is toxic to host cells. To identify less-toxic isoforms of the FMDV 3C protease, we screened 3C mutants for increased transgene output in comparison to wild-type 3C using a Gaussia luciferase reporter system. The novel point mutation 3C(L127P) increased yields of recombinant FMDV subunit proteins in mammalian and bacterial cells expressing P1-3C transgenes and retained the ability to process P1 polyproteins from multiple FMDV serotypes. The 3C(L127P) mutant produced crystalline arrays of FMDV-like particles in mammalian and bacterial cells, potentially providing a practical method of rapid, inexpensive FMD vaccine production in bacteria. IMPORTANCE The mutant FMDV 3C protease L127P significantly increased yields of recombinant FMDV subunit antigens and produced virus-like particles in mammalian and bacterial cells. The L127P mutation represents a novel advancement for economical FMD vaccine production.


2021 ◽  
Vol 8 ◽  
Author(s):  
Emma Brown ◽  
Graham Freimanis ◽  
Andrew E. Shaw ◽  
Daniel L. Horton ◽  
Simon Gubbins ◽  
...  

The sequencing of viral genomes provides important data for the prevention and control of foot-and-mouth disease (FMD) outbreaks. Sequence data can be used for strain identification, outbreak tracing, and aiding the selection of the most appropriate vaccine for the circulating strains. At present, sequencing of FMD virus (FMDV) relies upon the time-consuming transport of samples to well-resourced laboratories. The Oxford Nanopore Technologies' MinION portable sequencer has the potential to allow sequencing in remote, decentralised laboratories closer to the outbreak location. In this study, we investigated the utility of the MinION to generate sequence data of sufficient quantity and quality for the characterisation of FMDV serotypes O, A, Asia 1. Prior to sequencing, a universal two-step RT-PCR was used to amplify parts of the 5′UTR, as well as the leader, capsid and parts of the 2A encoding regions of FMDV RNA extracted from three sample matrices: cell culture supernatant, tongue epithelial suspension and oral swabs. The resulting consensus sequences were compared with reference sequences generated on the Illumina MiSeq platform. Consensus sequences with an accuracy of 100% were achieved within 10 and 30 min from the start of the sequencing run when using RNA extracted from cell culture supernatants and tongue epithelial suspensions, respectively. In contrast, sequencing from swabs required up to 2.5 h. Together these results demonstrated that the MinION sequencer can be used to accurately and rapidly characterise serotypes A, O, and Asia 1 of FMDV using amplicons amplified from a variety of different sample matrices.


2018 ◽  
Vol 6 (2) ◽  
pp. 23-26
Author(s):  
Mohammad Showkat Mahmud ◽  
Eusha Islam ◽  
Md. Giasuddin ◽  
Mohammed Abdus Samad ◽  
Md. Rezaul Karim ◽  
...  

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