Microplastics as a vector of pathogens contamination, infection and resistance: a case of Campylobacter in poultry production and processing

The Project addresses the most urgent problems of foodborne illnesses where Campylobacter are the leading global cause of gastroenteritis and they express the increasing antimicrobial resistance in the food supply chain. Furthermore, increased health risks due to the COVID-19 pandemic for adults of any age with chronic diseases or adverse medical conditions define the greater need for global control of Campylobacter contamination and infection. Campylobacter are well adapted to life in the intestines of animals and humans, so it is surprising that they can also survive on the surface of meat and following the best cleaning used to remove organic matter from facilities and equipment. Researchers have recently solved this puzzle, showing the enormous benefit for Campylobacter from multispecies biofilm communities. We are aware of sites prone to biofilm formation, but we are not aware of the presence of microplastics in the environment of poultry processing. Such microplastics can enormously increase the attachment area for bacteria, and thus they can persist through the food production processes. The objective of the Project is to understand the role of microplastics, as they provide an enormous surface area on which bacteria can attach, form biofilms, and potentially travel through the surrounding environments, each of which include the presence of variable microbial communities, food organic materials, and conditions such as the presence of antimicrobial drugs. This finally offers us a potential explanation, in that mobile biofilm communities on microplastics might have an essential role in the transmission of Campylobacter infection from animal reservoirs through production and processing to humans. This would solve the Campylobacter mystery, of how such microaerophilic Campylobacter that show limited hardiness and growth conditions can survive through the harsh conditions of food production and processing. The intensive use of antimicrobial agents, combined with the international trade in raw materials and food products, have increased persistent multidrug resistant strains, through activation of horizontal gene transfer of resistance genes through the replacement of homologous sequences, or the acquisition of mobile genetic elements. Microplastics can promote the diversity of biofilm communities, which will vary while moving through the surrounding environment, with increased horizontal transfer of resistance genes between bacteria. The Project data will be original and will explain the importance of spoilage biofilm formation on microplastics, and the role of these microplastics in survival, persistence and virulence of the foodborne pathogen Campylobacter. Another objective is to develop analytical methodologies for isolation and characterisation of microplastics from the poultry digestive tract and the end-products, which will allow us to highlight their transmission pathway through food production processes. The proposed Project will be realized by cooperation of Slovenian researchers (ARRS as a leading agency) from four organisations in partnership with Belgian partner (FWO as partner agency) in 5 Work Packages, with 21 Tasks and providing 15 Deliverables. The group from University of Ljubljana, Biotechnical Faculty (ULBF) led by Assoc. Prof. Dr. Anja Klančnik will coordinate the project as a world‐leading Campylobacter, Pseudomonas and biofilm research group. The group from Ghent University (UGent) will be led by world‐leading researcher Prof. Dr. Andreja Rajkovič in the field of microplastics, molecular biology, gut microbiome. Microplastics analysis will be supported by the group of Institute for Water of the Republic of Slovenia (IVRS) and group leader Dr. Manca Kovač Viršek. The group from Jožef Stefan Institute (IJS), led by Dr. Jerica Sabotič, will support the microscopy and FISH. The group from University of Ljubljana, Centre Compete (CC) will be led by Dr. Tadej Kokalj, with expertise in microfluidics.