Micah J Worley
Salmonella remains a serious public health threat. It is estimated to infect over 200 million people per year following inadvertent oral ingestion. It overcomes colonization resistance in part by initially exacerbating host inflammation. Salmonella actively invades host cells and extensively manipulates the endocytic pathway to create an intracellular niche conducive to its survival and growth. Salmonella counters the inflammation it initially contributes to with the deployment of numerous anti-inflammatory virulence factors to restore host homeostasis, allowing for a longer-term relationship with its host. This review covers the invasion of host cells by Salmonella and its intracellular replication and systemic spread strategies. Both the extensive manipulation of intracellular trafficking by some cells as well as escape from the vacuole and growth within epithelial cell cytosol by others are discussed. Also discussed are the typhoid toxin and Vi capsule.