What is generally true about the path of S. typhi in a human host following oral ingestion?

The path of S. typhi, or Salmonella Typhi, in a human host following oral ingestion is characterized by its ability to translocate across the intestinal epithelium. After ingestion, S. typhi survives in the acidic environment of the stomach and does not typically initiate infection in the large intestine. Instead, it travels to the small intestine, where it is equipped with specialized mechanisms, including the use of various virulence factors, that aid in its uptake into intestinal epithelial cells.

Once it translocates across the intestinal epithelium, S. typhi can enter the underlying tissue and subsequently gain access to the lymphatic and circulatory systems, leading to systemic infection and potentially affecting various organs including the liver and spleen. This translocation is a critical aspect of its pathogenicity, facilitating the establishment of the infection throughout the host.

This understanding of the pathway of S. typhi highlights why translocation across the intestinal epithelium is a crucial step in the infection process, contributing to the organism's ability to cause typhoid fever.