Invasive strains of Salmonella entericia serovar Typhi (Salmonella typhi) are capable of causing severe infection, intestinal hemorrhaging and epithelial perforation capable of killing its host. Salmonella typhi, the causative agent of typhoid fever, is mostly found in developing countries in Asia and can develop multi-drug resistance quickly through the use of plasmid vectors containing resistance factors. The mechanism through which Salmonella typhi infects its host is through the invasion of M cells in Peyer's patches found in the intestinal epithelium. Because of the commonality of typhoid fever symptoms with other less life-threatening diseases, methods for rapid diagnosis and treatment are needed in endemic areas. Although current treatment methods for Salmonella typhi infection are effective, there are still strains resistant to overused antibiotic drugs. The bactericidal effects of probiotics were studied against the pathogenic effects of Salmonella typhi and it was discovered that probiotics improved the overall intestinal health of hosts when infected with Salmonella typhi. This was accomplished through the use of bacteriocins but primarily through antimicrobial secretions containing organic acids. Additional research can be done to determine if probiotics are more or less efficient at eradicating this disease than antibiotics in stand-alone therapies. Combination therapies of antibiotics and probiotics have also been proven to produce synergistic effects when tested against Salmonella typhi.