OS20 Online 10 December

1. 1EuFMD | Open Session special edition | #OS20se
HyunJi Lee
Animal and Plant Quarantine Agency, Foot-and-mouth disease division /
Republic of Korea.
GENETIC CHARACTERIZATION OF
SEROTYPE AND GENETIC RELATEDNESS
OF FOOT-AND-MOUTH DISEASE VIRUSES
IN SOUTH EAST ASIA

2. 2EuFMD | Open Session special edition | #OS20se
Figure 2. The spreading of FMDV from Southeast Asia
into South Korea As exchanges between South Korea
and Southeast Asia have increased, the likelihood that
viruses from Southeast Asia will spread to South
Korea will increase.
Foot-and-mouth disease (FMD) is the most important disease of livestock, causing huge economic
impact on worldwide. FMD virus is a single strand of positive-sense RNA and over 8,000 bases in length.
The causative agent, FMD virus (FMDV), is divided into seven Serotype categories: A, O, C, Asia1, SAT1,
SAT2 and SAT3 based on VP1 sequence. Each serotype is divided into several topotypes and lineages by
genetic characterization. FMDV serotype O and A are the most prevalent in Southeast Asia containing
Vietnam, Laos, Cambodia, and Myanmar. Two different lineages of serotype O have been circulating in
Southeast Asia during 2018-2019; O/ME-SA/PanAsia and O/SEA/Mya-98. And A/ASIA/SEA97 of serotype
A also have been circulating in Southeast Asia. In Korea, FMDV serotype O/ME-SA/PanAsia was reported
in 2000 and 2002. O/SEA/Mya-98 was reported in 2010, 2014 and 2016, and A/ASIA/SEA97 was
reported in 2010 and 2018. With the recent increase in physical and human exchanges with Southeast
Asia, the possibility of introducing the FMDV serotype O/ME-SA/PanAsia into South Korea is increasing.
In this study, we collected 95 clinical FMDV samples between 2018 and 2019 in Vietnam, Laos and
Cambodia, analyzed genetic relatedness.
Figure 1. In South Korea, 11 foot-and-mouth disease cases have occurred since 2000, and only serotype O
and A have occurred.
Introduction

3. 3EuFMD | Open Session special edition | #OS20se
Figure 3. 95 clinical samples were collected that occurred between 2018 and 2019 from Vietnam, Laos
and Cambodia. Viral RNAs were extracted from the clinical samples and cells using a Nextracter
(Genolution). The 3D region in the virus genome was confirmed by qRT-PCR to determine whether the
collected samples were FMDV positive. The VP1 regions were amplified using a one-step RT-PCR
kit(Qiagen). PCR products were purified with ExoSAP-IT (USB) and directly sequenced on an ABI 3130
genetic analyzer(Applied Biosystems) using a Big Dye Terminator Kit v3.1(Applied Biosystems).
VP1 genome sequences were alinged by BioEdit and analyzed Phylogenetic tree estimated using the
Maximum-Likelihood method on the General Time Reversible model in MEGA-X version 10.0.1.
Figure 4.
A) It was possible to determine whether FMD was
positive or negative through 3D qRT-PCR. As a
result of analyzing 95 FMDV samples, 40 were
found to be FMD positive.
B) Major capsid protein, VP1 were amplified using
RT-PCR. Amplified PCR products were separated by
gel electrophoresis, stained with ethidium bromide.
A
B
FMDV from Vietnam, Laos, Cambodia (3D qRT-PCR)
Materials and Methods Results

4. 4EuFMD | Open Session special edition | #OS20se
Figure 5. Phylogenetic analysis of FMD positive samples from Vietnam, LAO, and
Cambodia. As a result of genome analysis based on the VP1 gene, Cambodia's
A/ASIA/SEA-97 and Vietnam's O/SEA/Mya98 each belong to one genetic cluster.
Some FMDVs in Cambodia and Vietnam and FMDV in Laos (n=1) belong to three
different genetic clusters in O/ME-SA/Panasia.
Results
FMDVs in Vietnam and Laos belonged to Serotype O and
classified into O/Me-SA/Panasia and O/SEA/Mya-98 genotypes.
FMDVs in Cambodia belonged to Serotype O and A, being
classified into O/ME-SA/Panasia and A/ASIA/SEA-97 genotype.
The further study may require investigation of antigenic
relatedness of the field FMDVs to strains of commercial FMD
vaccines. Also, Securing FMDV in a Pool 1 region and
accumulating the genetic information of the virus can provide
valuable information for further research on the genetic
diversity and antigenic relationship of FMDV to prevent and
control foot-and-mouth disease in South Korea in the future.
Conclusion

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EuFMD / Open Session