Unlike broad-host Salmonella serovars, which cause self-limiting disease, Salmonella enterica serovar Typhi can infect only humans causing typhoid fever, a life-threatening systemic disease. The molecular bases for these differences are presently unknown. Here we show that the GTPase Rab29 (Rab7L1) distinguishes the intracellular vacuole of human-adapted and broad-host Salmonella serovars. A sc...

The development of improved typhoid vaccines is a high global public health priority. However, their development has been hampered by a lack of information regarding the specific determinants of protective immunity to Salmonella enterica serovar Typhi (S. Typhi) infection in humans. Although antibodies to S. Typhi O, H, and Vi appear to be involved in protection against S. Typhi infection, it i...

BACKGROUND Salmonella typhi may be a cause of significant morbidity and mortality in both the mother and fetus. Febrile illness during pregnancy, especially that associated with hemolysis, is associated with chorioamnionitis, pyelonephritis, or viral syndrome. As such, S. typhi should be considered when a patient presents with a fever and hemolysis. We present a case of S. typhi complicating pr...

Strains of Salmonella typhi isolated from the blood of patients with typhoid fever invariably express a capsular polysaccharide, termed the Vi antigen. Vi antigen expression is controlled by two separate chromosomal loci, viaA and viaB. The viaA locus is commonly found in enteric bacteria. In contrast, the viaB locus appears to be specific to Vi-expressing strains of Salmonella and Citrobacter....

BACKGROUND & AIMS Systemic cellular immunity elicited by the Ty21a oral typhoid vaccine has been extensively characterized. However, very limited data are available in humans regarding mucosal immunity at the site of infection (terminal ileum [TI]). Here we investigated the host immunity elicited by Ty21a immunization on terminal ileum-lamina propria mononuclear cells (LPMC) and peripheral bloo...

Multi-locus variable-number tandem repeat analysis differentiated 297 Salmonella enterica serovar Typhi blood culture isolates from Makassar in 76 genotypes and a single unique S. Typhi genotype was isolated from the cholecystectomy specimens of four patients with cholelithiasis. The high diversity in S. Typhi genotypes circulating in Makassar indicates that the number of carriers could be very...

The indirect fluorescent antibody test using a whole Salmonella typhi Vi suspension as the antigen has been evaluated for the diagnosis of typhoid fever. Results using sera from 140 patients with S typhi infections proved on culture show the test to have good sensitivity. The test appears to be highly specific, although it has not yet been investigated with respect to typhoid vaccination or in ...

A DNA probe was used to detect Salmonella typhi from blood samples from 14 of 33 patients with culture-confirmed typhoid fever, using the equivalent of 2.5 ml of blood. In contrast, S. typhi was detected in 17 of the same 33 patients by culture of 8 ml of blood. The probe hybridized to blood samples of 4 of 47 patients from whom S. typhi was not isolated.

Salmonella enterica serovar Typhi expresses a capsule of Vi polysaccharide, while most Salmonella serovars, including S. Enteritidis and S. Typhimurium, do not. Both S. Typhi and S. Enteritidis express the lipopolysaccharide O:9 antigen, yet there is little evidence of cross-protection from anti-O:9 antibodies. Vaccines based on Vi polysaccharide have efficacy against typhoid fever, indicating ...

Enteric fever, caused by Salmonella enterica, remains an unresolved public health problem in India and antimicrobial therapy is the main mode of treatment. The objective of this study was to characterize the Salmonella enterica isolates from Kolkata with respect to their antimicrobial resistance (AMR), virulence profiles and molecular subtypes. Salmonella enterica blood isolates were collected ...