Project 2

Project summary

The EPIG project directly addresses Call Topic 2 and Action OO7 of the EUPAHW objectives by deepen-ing scientific understanding and knowledge to underpin new methods for controlling S. suis invasive disease. Outbreaks of S. suis diseases are very common in weaning piglets, associated with a substantial impairment of animal welfare, economic losses, often leading to metaphylactic application of antibiotics [1]. S. suis is also an emerging zoonotic pathogen causing severe infections in humans, with most cases occurring in southeast Asia [2, 3].

The project builds on the applicant’s recent population genomics re-search on more than 3000 S. suis isolates showing that emergence of the pathogenic lineages of S. suis coincided with the acquisition of three specific genomic pathogenicity-associated islands (PAIs) through intra- and inter-species horizontal gene transfer. Researchers aim to elucidate the functions of three (PAIs) predicted to enable S. suis to compete with other microbiota species, one of which is also important for pathogenesis. Detection methods based on these PAIs will also be used to understand the prevalence and transmission pathways of pathogenic S. suis on farms from 5 countries, laying the groundwork for new diagnostic technologies to target interventions in carrier sows. The project will also assess the effectiveness of different immunoglobulins in reducing S. suis carriage in the oropharyngeal cavity of piglets to support future immune exclusion interventions. Finally, the project aims to identify humoral responses to conserved surface proteins in pathogenic isolates of S. suis, including those encoded in the PAI that could provide cross-protection and be used for immune exclusion by vaccination of sows.