Emergency response for recently isolated Foot and Mouth Disease virus type A Africa in Egypt 2022

Foot and mouth disease (FMD) is a highly contagious viral infection affecting cloven-hoofed ruminants, leading to significant economic losses. In 2022, Egypt faced a severe outbreak of Foot and Mouth Disease (FMD) caused by the A/Africa/G-IV variant. This study assessed the efficacy of local and imported FMDV vaccines (A Iran-05 lineage) against this new variant using in vitro and in vivo methods. Sera from vaccinated calves showed inadequate cross-protection, with mean r1-values of 0.235 and 0.243 for local and imported vaccines, respectively. Challenge tests indicated low protection levels (20% and 40%) against A/Africa/G-IV compared with A/Iran/05. Current vaccines were deemed ineffective, prompting a formulation update incorporating the variant. The modified vaccine is now deployed in proactive vaccination efforts to address the evolving FMD outbreak.