The impact of climate change on existing and emerging microbial threats across the food chain: An island of Ireland perspective††This paper is one of a series of reviews on “Climate Change and Food Safety – an Island of Ireland perspective”

The One Health aspect of climate events with impact on foodborne pathogens transmission

The ongoing effects of climate change have exacerbated two significant challenges to global populations: the transmission of foodborne pathogens and antimicrobial resistance (AMR) through the food chain. Using the latest available scientific information this review explores how climate-related factors such as rainfall, floods, storms, hurricanes, cyclones, dust, temperature and humidity impact the spread of the foodborne pathogens Salmonella, E. coli, Campylobacter, Vibrio, Listeria, and Staphylococcus aureus. We explore the complex dynamics between environmental changes and the heightened risk of foodborne diseases, analysing the contribution of wildlife, insects and contaminated environments in the proliferation of AMR and climate change. This review paper combines a thorough analysis of current literature with a discussion on findings from a wide variety of studies to provide a comprehensive overview of how climatic factors contribute to the survival, persistence and transmission of bacterial pathogens in the food chain. In addition, we discuss the necessity for effective mitigation strategies and policies. By providing insights into the interrelationships between climate change and food safety, this review hopes to inform future research and policy development to promote safer and more sustainable food systems and further integration within the One Health approach.

Weather correlates of Campylobacter prevalence in broilers at slaughter under tropical conditions in Sri Lanka

Campylobacter is the primary agent of human bacterial gastroenteritis worldwide. In contrast to temperate zones, weather effects on Campylobacter prevalence in broilers under tropical conditions are under-researched. We examined the association between weather and Campylobacter prevalence in slaughtered broilers in Sri Lanka, a tropical country with weather variations led by monsoons. Each month (October 2009-July 2011), 20-30 broiler batches referring to two semi-automated slaughterhouses from five Sri Lankan provinces were tested for Campylobacter contamination and analysed in relation to temperature, humidity and rainfall. Overall prevalence was 63.8% (95% CI 59.6-67.9%, n = 542), peaking in September-November. Each 1 °C increase in monthly mean temperature up to 26 °C increased Campylobacter-positive batches by 16.4% (95% CI 0.4-35.1%). For each 10 mm increase in monthly total rainfall up to 300 mm, Campylobacter-positive batches increased significantly by 0.8% (0.1-1.5%) at 1-month lag. For each 1% increase in relative humidity up to 80% at 1- and 2-month lags, Campylobacter-positive batches increased of respectively 4.2% (1.9-6.7%) and 4.0% (1.5-6.5), and decreased by 3.6% (2.6-4.6%) and 4.0% (2.6-5.4%) for unit increases above 80%. These results suggest that even in tropical countries without marked seasons, there are weather effects possibly reflecting Campylobacter potential to colonise its preferred host and/or survive in the environment.

Antibacterial Derivatives of Marine Algae: An Overview of Pharmacological Mechanisms and Applications

The marine environment is home to a taxonomically diverse ecosystem. Organisms such as algae, molluscs, sponges, corals, and tunicates have evolved to survive the high concentrations of infectious and surface-fouling bacteria that are indigenous to ocean waters. Both macroalgae (seaweeds) and microalgae (diatoms) contain pharmacologically active compounds such as phlorotannins, fatty acids, polysaccharides, peptides, and terpenes which combat bacterial invasion. The resistance of pathogenic bacteria to existing antibiotics has become a global epidemic. Marine algae derivatives have shown promise as candidates in novel, antibacterial drug discovery. The efficacy of these compounds, their mechanism of action, applications as antibiotics, disinfectants, and inhibitors of foodborne pathogenic and spoilage bacteria are reviewed in this article.