Foot-and-mouth disease (FMD) is a highly contagious disease of livestock affecting animal production and trade throughout Asia and Africa. Understanding FMD virus (FMDV) global movements and evolution can help to reconstruct the disease spread between endemic regions and predict the risks of incursion into FMD-free countries. Global expansion of a single FMDV lineage is rare but can result in severe economic consequences. Using extensive sequence data we have reconstructed the global space-time transmission history of the O/ME-SA/Ind-2001 lineage (which normally circulates in the Indian sub-continent) providing evidence of at least 15 independent escapes during 2013–2017 that have led to outbreaks in North Africa, the Middle East, Southeast Asia, the Far East and the FMD-free islands of Mauritius. We demonstrated that sequence heterogeneity of this emerging FMDV lineage is accommodated within two co-evolving divergent sublineages and that recombination by exchange of capsid-coding sequences can impact upon the reconstructed evolutionary histories. Thus, we recommend that only sequences encoding the outer capsid proteins should be used for broad-scale phylogeographical reconstruction. These data emphasise the importance of the Indian subcontinent as a source of FMDV that can spread across large distances and illustrates the impact of FMDV genome recombination on FMDV molecular epidemiology.

Foot and Mouth Disease (FMD) is a high-impact, contagious transboundary animal disease that is endemic in Southeast Asia. Abattoir samples were routinely collected in six selected provinces between March and December 2019. A total of 1280 samples of abattoir animals were tested for FMD Non-Structural Protein (NSP) antibodies to indicate natural infections. Overall, 22.8% were seropositive for FMD NSP antibodies while seroprevalence of cattle (n = 469), buffalo (n = 214), and pigs (n = 597) were 44.6%, 35.0%, and 1.3%, respectively. The highest seroprevalence destination province was Xiengkhouang (35.3% of 272 samples), followed by Savannakhet (27.0% of 244 samples). Risk factors for evidence of natural infection identified by a multivariate logistic regression model included age groups (p-value = 0.02) and origin provinces (p-value = 2.8 × 10−5) of the animals. There were significant differences of FMD NSP seroprevalence between age groups and origin provinces of the animals. The odds ratio of a seropositive result in the less than 1 year old group was 2.5 (95% CI; 1.4, 4.4) when compared to the 3–4 years old group, while the odds ratios for animals that originated from Khammouane and Xiengkhouang provinces were 4.5 (95% CI; 1.1, 18.7) and 2.4 (95% CI; 1.4, 4.1), respectively, when compared to Champasak province. Serotype-specific antibody ELISA for 44 NSP antibody–positive samples revealed evidence of FMD serotypes O and A virus circulation in some provinces. Despite the passive abattoir survey providing useful information on FMD virus previous exposure and geographic locations of the animals, timely information on FMD virus circulation and distribution is also crucial to an effective control program. Alternative approaches to increase the cost-effectiveness of the surveillance network are also discussed.

No abstract

Understanding of disease dynamics and viral shedding in wild boar and of the potential for disease spreading within wild boar and domestic pig populations is critical for developing effective control and eradication measures for foot-and-mouth disease (FMD). Accordingly, we infected experimentally wild boar and domestic pigs with FMD virus (FMDV) strains O/TAI/315/2016 and A/MOG/2013, and studied their susceptibility and viral transmissibility in both populations. Similar to FMDV-infected pigs, wild boar inoculated with both viruses exhibited vesicular lesions on their feet, snout, tongue and lip, although they did not show lameness. Further, inoculated wild boar were equally capable of transmitting the virus to all of their contact animals. While all contact pigs developed vesicular lesions after contact with inoculated animals, in contrast, no wild boar when exposed to the same infected animals showed obvious clinical signs. These results will be useful for further understanding of the critical roles in occurring and sustaining an FMD outbreak, and will be useful for establishing epidemiological surveillance programs and effective countermeasures for wild boar.

Here, we report near-complete genome sequences of three foot-and-mouth disease viruses isolated in 2016 from bovine and porcine epithelial tissue samples collected in Nonthaburi, Songkhla, and Ratchaburi provinces, Thailand. These viruses were classified as serotype O, topotype ME-SA, and sublineage Ind-2001e.