Evolutionary and Ecological Drivers Shape the Emergence and Extinction of Foot-and-Mouth Disease Virus Lineages.

Livestock farming across the world is constantly threatened by the evolutionary turnover of foot-and-mouth disease virus (FMDV) strains in endemic systems, the underlying dynamics of which remain to be elucidated. Here, we map the eco-evolutionary landscape of cocirculating FMDV lineages within an important endemic virus pool encompassing Western, Central, and parts of Southern Asia, reconstructing the evolutionary history and spatial dynamics over the last 20 years that shape the current epidemiological situation. We demonstrate that new FMDV variants periodically emerge from Southern Asia, precipitating waves of virus incursions that systematically travel in a westerly direction. We evidence how metapopulation dynamics drive the emergence and extinction of spatially structured virus populations, and how transmission in different host species regulates the evolutionary space of virus serotypes. Our work provides the first integrative framework that defines coevolutionary signatures of FMDV in regional contexts to help understand the complex interplay between virus phenotypes, host characteristics, and key epidemiological determinants of transmission that drive FMDV evolution in endemic settings.

Genome Sequences of Foot-and-Mouth Disease Virus O/ME-SA/Ind-2001e Strains Isolated in Pakistan.

The genome sequences of two foot-and-mouth disease type O viruses isolated from outbreaks of disease in cattle in Pakistan in 2019 are described. They were identified as belonging to serotype O, Middle East-South Asia topotype, Ind-2001 lineage, and e sublineage and represent the first identification of this lineage in Pakistan.

An appraisal on the occurrence of foot-and-mouth disease virus serotypes in cattle and buffaloes, Pakistan.

Foot-and-mouth disease (FMD) is a livestock disease that has serious economic repercussions. Here, we report the laboratory results for samples from suspected outbreaks that were sent for confirmation of FMD in Pakistan. From January 2010 to December 2011, 132 suspected outbreaks were investigated, and samples from 58 out of the 76 outbreaks sent to the National Veterinary Laboratory (NVL) were positive. The highest proportion of positives were of serotype O (65.52 %), followed by serotype A (24.14 %) and serotype Asia-1 (10.35 %), whereas amongst the samples sent to the World Reference Laboratory, Pirbright, UK (WRL), samples from 48 out of 56 outbreaks were confirmed to be FMD positive, with the following serotypes identified: O (56.25 %), Asia-1 (37.50 %) and A (6.25 %). The outbreaks affected cattle, buffalo and mixed (cattle and buffalo) herds at rates of 91, 70 and 76 %, respectively. The trend of positive outbreaks was higher in the months of winter and late spring (November to April). Although the serotype O isolates and some of the serotype A isolates from the field samples resembled the vaccine strains (r-value ≥ 0.3), this was not the case for the Asia-1 isolates. These results help to improve our understanding of the occurrence and distribution of FMD in cattle and buffaloes in Pakistan and to provide baseline information for the FMD progressive control program in the country.