Clinical, molecular detection and phylogenetic analysis study of local foot-and-mouth disease virus in Al-Qadisiyah province of Iraq.

Abstract

Aim:This study was directed during an outbreak of suspected foot-and-mouth disease (FMD) in cattle in Al-Qadisiyah province, Iraq 2016. The disease has made a huge economic loss in livestock. It was suspected that the vaccination has failed to protect the animals from the infection because of the difference in the strains. Consequently, we designed the study to make the diagnosis and detect the strain of the causative virus.Materials and Methods:The extraction of the DNA was done on 73 samples and Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) was used in the detection of FMD virus (FMDV) for primary diagnosis, and serotype-specific diagnosis was done with universal primer sets 1F/1R, A-1C612, and O-ARS4 with the expected band of 329, 865, and 1301 bp, respectively.Results:Universal primer pair 1F/1R detected FMD in 55 of 73 (75.3%); of these, 37 (67.3%) were females and 18 (32.7%) were males, with high significance (p<0.01) between males and females in the PCR positivity ratio. The tested samples with positive universal primer were amplified with specific primers A-IC612 with no reaction for serotype O-ARS4.Conclusion:The products of RT-PCR were sent for RNA sequencing, and the results were 100% positive to serotype A which means that it is the predominant type in Iraq. It may help in the importing or production of the vaccine to make a preventive plan for the disease. The virus of FMD is contagious and dangerous due to its role in the huge economic loses. The detection of this virus is widely explained in lots of articles, but it is more specific and sensitive in RT-PCR and sequencing. Consequently, the authorities responsible for importing and/or production vaccines have to avoid the importing of other serotypes because it will be losing money and more outbreaks will explode.