Salmonella enterica serovar Typhi (S. Typhi), the causative agent of typhoid fever, continues to cause significant morbidity and mortality world-wide. CD8+ T cells are an important component of the cell mediated immune (CMI) response against S. Typhi. Recently, interleukin (IL)-17A has been shown to contribute to mucosal immunity and protection against intracellular pathogens. To investigate mu...

Neonates respond poorly to conventional vaccines. This has been attributed, in part, to the immaturity of neonatal dendritic cells that lack full capacity for Ag presentation and T cell stimulation. We engineered an attenuated Salmonella Typhi strain to express and export the F1 Ag of Y. pestis (S. Typhi(F1)) and investigated its immunogenicity early in life using a heterologous prime-boost reg...

From 1977 to 1986, Chile experienced an important typhoid fever epidemic, despite statistics that indicated apparently improving levels of sanitation of drinking water and sewage disposal. The lack of antibiotic resistance among the Salmonella typhi strains isolated during this period, the mild clinical presentation of the disease, and the initially low level of efficacy of the S. typhi Ty21a v...

Typhoid fever is becoming an ever increasing threat in the developing countries. We have improved considerably upon the existing PCR-based diagnosis method by designing primers against a region that is unique to Salmonella enterica subsp. enterica serovar Typhi and Salmonella enterica subsp. enterica serovar Paratyphi A, corresponding to the STY0312 gene in S. Typhi and its homolog SPA2476 in S...

nfection with Salmonella enterica serovar Typhi Iresults in nearly 250,000 deaths and more than 21 million illnesses worldwide. S Typhi is transmitted through the fecal-oral route through contaminated food or water and therefore is a major global health problem in regions that lack the infrastructure to provide safe water and ensure adequate sanitation. Of the 2 widely used S Typhi vaccines, Ty...

Salmonella spp. are gram-negative flagellated bacteria that can cause food- and waterborne gastroenteritis and typhoid fever in humans. We now report that flagellin from Salmonella spp. is recognized in mouse intestine by Toll-like receptor 11 (TLR11). Absence of TLR11 renders mice more susceptible to infection by S. Typhimurium, with increased dissemination of the bacteria and enhanced lethali...

We analysed the record of blood cultures carried out at the Armed Forces Institute of Pathology, Rawalpindi between 1996 and 2003. We isolated 477 Salmonella typhi and 410 S. paratyphi A from blood of patients suffering from typhoid fever. We observed a significant shift in the distribution and antimicrobial susceptibility of typhoid salmonellae. The isolation rate of S. typhi fell significantl...

INTRODUCTION It is important to identify Salmonella Typhi infection quickly to treat acute fever patients and to prevent transmission by chronic typhoid carriers; therefore, a very specific and sensitive diagnostic technique is highly desirable, especially in endemic areas. The objective of this study was to develop a PCR protocol targeting the putative fimbrial staA gene of S. Typhi. This is a...

INTRODUCTION Dengue fever is endemic in developing nations worldwide with as many as 500,000 annual cases of dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). A prompt and accurate diagnosis early in the disease course is essential for prompt identification and treatment of severe complications of the dengue virus infection (DVI). We identified cross-reactivity of a rapid IgM test...

Background: Virulence of S. typhi possessed an important factor for occurrence of typhoid fever in humans. Penetration of S. typhi in the intestinal mucosa is an important step in the establishment of infection because it allows microorganisms to pass through the epithelial barrier. This penetration is mostly determined by the motility of bacteria. Flagella are composed of a protein called flag...