Transcriptional response in the peripheral blood of patients infected with Salmonella enterica serovar Typhi.

We used microarrays and transcriptional profiling of peripheral blood to investigate the host response of 29 individuals who contracted typhoid fever in the Mekong Delta region of Vietnam. Samples were taken over a nine month period encompassing acute disease, convalescence, and recovery. We found that typhoid fever induced a distinct and highly reproducible signature in the peripheral blood that changed during treatment and convalescence, returning in the majority of cases to the "normal" profile as measured in healthy uninfected controls.

Interaction of Salmonella enterica serovar Typhi with cultured epithelial cells: roles of surface structures in adhesion and invasion.

In this study we investigate the ability of Salmonella enterica serovar Typhi (S. Typhi) surface structures to influence invasion and adhesion in epithelial cell assay systems. In general, S.

Antibodies to the Vi capsule of Salmonella Typhi in the serum of typhoid patients and healthy control subjects from a typhoid endemic region.

Background: There is very little published data on the antibody response to the Vi capsular polysaccharide (Vi-CPS) of S. Typhi during naturally acquired typhoid fever in an endemic area.

Methodology: An indirect ELISA, using tyraminated, purified Vi-CPS, was used to assay anti-Vi-CPS antibodies from typhoid fever cases and controls living in the Ho Chi Minh City and Mekong Delta region of Viet Nam.

A TNF region haplotype offers protection from typhoid fever in Vietnamese patients.

The genomic region surrounding the TNF locus on human chromosome 6 has previously been associated with typhoid fever in Vietnam (Dunstan et al. in J Infect Dis 183:261-268, 2001). We used a haplotypic approach to understand this association further.

Use of paired serum samples for serodiagnosis of typhoid fever.

Using an enzyme-linked immunosorbent assay we demonstrate that, in adult patients with typhoid fever, the sensitivity of a serological test based on the detection of anti-lipopolysaccharide immunoglobulin G is increased when used with paired serum samples taken 1 week apart.

Vi antigen expression in Salmonella enterica serovar Typhi clinical isolates from Pakistan.

The accurate identification of Salmonella enterica subsp. enterica serovar Typhi variants that fail to express the capsular polysaccharide, Vi, is an important and much discussed issue for medical microbiology. We have tested a multiplex PCR method which shows the presence or absence of the genetic locus required for Vi expression.

Host susceptibility and clinical outcomes in toll-like receptor 5-deficient patients with typhoid fever in Vietnam.

Toll-like receptor 5 (TLR5) mediates innate immune responses to bacterial pathogens by binding to flagellin. A polymorphism in the TLR5 gene introduces a premature stop codon (TLR5(392STOP)) that is associated with susceptibility to legionnaires disease. Here we investigated whether TLR5(392STOP) was associated with typhoid fever.

Proinflammatory cytokines and chemokines in humans with Japanese encephalitis.

Background: Japanese encephalitis virus (JEV), the mosquito-borne flavivirus, annually causes an estimated 35,000-50,000 encephalitis cases and 10,000-15,000 deaths in Asia, and there is no antiviral treatment. The role played by the immune response in determining the outcome of human infection with JEV is poorly understood, although, in animal models of flavivirus encephalitis, unregulated proinflammatory cytokine responses can be detrimental.

Methods: We studied the innate, cellular, and humoral immune responses in 118 patients infected with JEV, of whom 13 (11%) died.

A clinical, microbiological, and pathological study of intestinal perforation associated with typhoid fever.

One of the most serious complications of typhoid fever is intestinal perforation. Of 27 patients admitted to a provincial hospital in the Mekong Delta region of Vietnam who had gastrointestinal perforation secondary to suspected typhoid fever, 67% were male, with a median age of 23 years and a median duration of illness of 10 days. Salmonella enterica subspecies enterica serotype Typhi (S.

The role of prophage-like elements in the diversity of Salmonella enterica serovars.

The Salmonella enterica serovar Typhi CT18 (S.Typhi) chromosome harbours seven distinct prophage-like elements, some of which may encode functional bacteriophages. In silico analyses were used to investigate these regions in S.

Double blind comparison of ibuprofen and paracetamol for adjunctive treatment of uncomplicated typhoid fever.

Background: Antipyretics reduce the prolonged, high fever characteristic of typhoid fever. The benefits of nonsteroidal drugs in this role have not been quantified. There have been concerns about the safety of antipyretics in typhoid.

Cytokine release by lipopolysaccharide-stimulated whole blood from patients with typhoid fever.

The ex vivo cytokine response to lipopolysaccharide (LPS) of whole blood from patients with typhoid fever was investigated. Tumor necrosis factor (TNF)-alpha release by LPS-stimulated blood was found to be lower during acute typhoid fever than after a course of antimicrobial therapy (P View Article and Find Full Text PDF

Characterization of Salmonella enterica derivatives harboring defined aroC and Salmonella pathogenicity island 2 type III secretion system (ssaV) mutations by immunization of healthy volunteers.

The attenuation and immunogenicity of two novel Salmonella vaccine strains, Salmonella enterica serovar Typhi (Ty2 Delta aroC Delta ssaV, designated ZH9) and S. enterica serovar Typhimurium (TML Delta aroC Delta ssaV, designated WT05), were evaluated after their oral administration to volunteers as single escalating doses of 10(7), 10(8), or 10(9) CFU. ZH9 was well tolerated, not detected in blood, nor persistently excreted in stool.

Unlocking the genome of the human typhoid bacillus.

Molecular studies are shedding new light on the pathogenesis of human typhoid fever, which is still a very common disease in developing countries. For example, the total genome DNA sequence has recently been determined for a multiple-drug-resistant Salmonella typhi, the serotype that is the cause of typhoid fever. The genome sequence showed many distinguishing features, including clusters of S typhi specific genes and a large number--over 200--of pseudogenes.