Recent progress in vaccines against foot-and-mouth disease

Abstract

Foot-and-mouth disease (FMD) is the most highly contagious disease affecting livestock resulting in a significant adverse economic impact worldwide. Disease outbreaks in previously FMD-free countries are initially controlled by the culling of infected and in-contact animals, restriction of susceptible animal movement, and vaccination with an inactivated whole-virus antigen preparation. With increasing trade, commerce globalization, and people migration, it is likely that more inter-pool viral exchanges and spillovers will occur posing a greater threat to both, endemic and non-endemic regions, mostly due to the limited antigenic coverage of current vaccines. Currently available inactivated FMD vaccines have a number of disadvantages, including incomplete inactivation of the virus, they require multiple vaccination to maintain good levels of immunity and periodic inclusion of new viral strains into the vaccine formulation to cover new FMDV subtypes against which existing vaccines no longer protect and lack differentiation of infected from vaccinated animals (DIVA). The essential aim of DIVA strategy is realization of the so-called “vaccinate-to-live” policy, which is based on the principles that vaccinated animals exposed to FMDV will not transmit the virus. To address the shortcomings of inactivated vaccines, many efforts are currently devoted to developing novel FMD vaccines, including attenuated and marker inactivated vaccines, recombinant protein vaccines, synthetic peptide vaccines and empty capsid vaccines. Novel vaccine platforms offer promising alternatives for effective FMD control. It is likely that in the near future, multiple FMD vaccine approaches will compete for diverse markets, providing fit-for purpose solutions to evolving challenges in preventing and controlling FMD worldwide.

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

“…e causative agent of FMD is an Aphthovirus in the family Picornaviridae and is classified into seven distinguishable serotypes and their respective topotypes [14,15]. Each of the seven FMDv serotypes is immunologically distinct; antibodies raised against one serotype cannot confer protection against another FMDv serotype and sometimes even within the same serotype [16].…”

Foot-and mouth disease and peste des petits ruminants – the role of wildlife in the epidemiology and control of diseases

“…Additionally, these vaccines do not strictly have differentiation of infected from vaccinated animal (DIVA) characteristics (16). To overcome the shortcomings of inactivated vaccines, many efforts are currently devoted to developing novel FMD vaccines, including recombinant protein vaccines, synthetic peptide vaccines and empty capsid vaccines (36).…”

Toxicity level of the tulathromycin on BHK cell culture and the effect on infective titers of foot and mouth disease viruses

“…The serotype O, A, and C viruses have had the widest distribution and have been responsible for outbreaks in Europe, America, Asia, and Africa. The FMDV particle is roughly spherical in shape, and, about 25-30 nm in diameter (20,25). It consists of the RNA genome surrounded by a protein shell or capsid (15,23).…”

“…It causes heavy economic losses to the livestock industry, such as a high morbidity in adult animals, treatment costs, reduced milk production, loss of working ability in draught animals in developing countries, reproductive disorders, and high mortality in young ones (13,19,24). The control of FMD is a national and regional responsibility, and, in many countries, the vaccine may be used only under the control of a veterinary authority (20,35). Sensitive cell culture systems include primary bovine (calf) thyroid cells and primary pig, calf, or lamb kidney cells.…”