Foot-and-Mouth Disease (FMD) commonly known as ‘Khura Rog’ in Bangladesh, is a highly contagious viral disease of cloven-hoofed animals mainly cow, goat and sheep. FMD outbreak has a devastating effect on the economy of a country. In Bangladesh, the low and middle income rural farmers become economically vulnerable due to FMD outbreak. Recent statistical data showed that the morbidity in cattle is approximately 36%, in buffalos 23%, and in goat/sheep 5%. Vaccination appears to be one of the most effective strategies to prevent FMD infection.
The etiological agent of this disease is Foot-and-Mouth Disease Virus (FMDV), a member of Aphthovirus genus under the Picrornaviridiae family. This is a single stranded positive sense RNA virus of about 8.5 Kb in length. Like other RNA virus, it lacks proof reading activity which usually generates quasispecies in every round of replication. This high rate of mutation is the barrier to develop safe and effective vaccines for FMD.
Moreover, there are seven immunologically distinct serotypes of FMDV, they are Type O, A, Asia1, SAT1-3. No cross protection was reported for the serotypes. Vaccine escape mutation may also compromise the protection with even after vaccination. So continuous monitoring is necessary to protect this contagious disease.
In Bangladesh, vaccines are available in the local markets that are produced against the FMD virus of foreign strain. Sometimes this causes the emergence of new virus strain. To date there was no genetic data that can reveal the circulatory serotypes of FMDV in our territory.
Our group especially focuses on the determination of the circulatory virus serotypes in Bangladesh, genome wide analysis of the circulatory strain and continuous monitoring at field level to check the efficiency of vaccine and disease status.
From 2011 our group has been concentrating on this issue. Our achievements can be pointed out like:
1) 3 FMDV serotypes found to be circulated in Bangladesh, they are Type O, A, Asia1.
2) In 2011-2012 Type O and A was responsible for the outbreaks in Bangladesh.
3) In 2012-2013 Type O and Asia1 was responsible for the outbreaks in Bangladesh.
4) Evidence of vaccine escape mutation was reported.
5) Adaptation of virus culture in BHK-21 cell line.
6) Isolation of virus [Type O and Type A] from cell culture supernatant.
7) Complete genome sequence Foot-and-Mouth Disease Type O [BAN/NA/Ha-156/2013, accession number KF985189].
8) Complete genome sequence Foot-and-Mouth Disease Type A [BAN/GA/Sa-197/2013, accession number KJ754939].