One health review of recent Salmonella dynamics and human health outcomes in the United States

Abstract

This review assessed the combined impact of poultry production, climate variability, and agricultural environments on human salmonellosis risk across the United States. It considers whether regions with both high poultry production and notable climate variability show amplified infection patterns and whether environmental transmission pathways are becoming more prominent alongside direct poultry exposure. A comprehensive systematic literature review in PubMed was conducted following PRISMA guidelines for studies published between 2011 and 2025 addressing Salmonella in relation to human incidence, poultry processing and environmental exposure. Our search yielded 22 studies that met the inclusion criteria and it included a range of methods such as surveillance, epidemiological modeling, and intervention research across different U.S. regions. The key analytical variables included were serotype diversity, seasonal and regional distribution, antimicrobial resistance, and climate-related environmental transmission. The findings revealed significant geographic overlap between areas of intensive poultry production and high salmonellosis rates, especially in the southern states. A rise in multidrug-resistant serovars, such as S. infantis in poultry products, was found. Seasonal contamination patterns showed chicken cuts peaking in contamination during late winter, in contrast to the summer peak of human cases. We also observed that temperature extremes and heavy precipitation were linked to increased environmental contamination, particularly of water sources, and higher human exposure risk. These conditions also influenced serotype prevalence and the distribution of resistance genes. As a result, there is a need for integrated One Health strategies that should include adaptive poultry management, climate-responsive environmental monitoring with a focus on serotype-specific risk assessment to reduce the overall public health impact of Salmonella.