View clinical trials related to Typhoid Fever.
Filter by:Typhoid fever is an illness that may cause mild effects in children, such as fever and feeling tired, or it may cause serious effects-- even death. A new typhoid vaccine has recently been recommended by the World Health Organization (WHO) to prevent typhoid in children. But this new typhoid vaccine has not been tested with all of the vaccines given to children in Burkina Faso. The investigators want to look at this new vaccine, and study how safe it is in children in Burkina Faso and how their immune systems respond to the vaccine when given with other vaccines, such as yellow fever and meningitis A vaccines. The investigators plan to vaccinate 100 children between the ages of 9-11 months, and 150 children between the ages of 15 months and 2 years, in Ouagadougou, Burkina Faso, with either the typhoid vaccine or a vaccine against another illness called polio. Children will have follow-up visits on days 3, 7, 28 and 180. One teaspoon of blood will be collected on days 0 and 28.
Typhoid fever caused by Salmonella Typhi and Paratyphi causes over 21 million cases of febrile illness and 200,000 deaths are attributed to enteric fever each year. Typhoid fever is an enteric infection that results in febrile illness. Typhoid fever causes significant morbidity in the developing world especially young children.S. Typhi specific antibody responses are elicited in typhoid fever and following typhoid vaccination. Cross-reactive multifunctional CD+4 T cell mediated IL-17 responses have been shown in typhoid fever. As S. Typhi as an intracellular pathogen, cellular immune responses might be central to protection. S. Typhi peptide subunit vaccine elicits CD+4 T cell responses that correlate with protection in mice. The role of mucosal associated invariant T cell (MAIT) and natural killer (NK) cell responses in typhoid fever or following vaccination remain poorly understood. Transcriptome profiling of human immune responses to S. Typhi infection is not clearly understood. Establishing successful infection by S. Typhi evasion of T cell and neutrophil responses need to be investigated to better understand the correlates of protection.
The purpose of this study is to evaluate the impact of a government-led typhoid conjugate vaccine introduction program on typhoid disease burden in Navi Mumbai, India.
This is a randomized, observer-blinded Phase 2 study in healthy infants and toddlers 6-23 months of age at the time of the first vaccine dose. The purpose of this study is to assess the safety and immunogenicity of the Vi-DT vaccine in age group 6-23months of age. The Vi-DT vaccine is administered at 25 µg either as a single dose, or two doses given 6 months apart.
This study is to assess the safety and immunogenicity of Vi-DT vaccine in adults, adolescent, children and infants.
The purpose of this study is to use an existing, unique clinical cohort: the longitudinal cohort of younger (21-40 years) and elderly (>65 years) subjects whose yearly influenza vaccine responses have been studied extensively since 2007, to gain molecular and cellular mechanistic insights into the impaired vaccine responses in the elderly.
This study will evaluate the efficacy of a Typhoid conjugate vaccine (Vi-TCV) in Malawi, Africa among children age 9 months through 12 years. Participants will be randomized in a 1:1 ration to receive the study vaccine or the control vaccine (meningococcal group A conjugate vaccine - MCV-A).
Typhoid fever results from infection with a bacterium called Salmonella Typhi and is a major cause of illness worldwide. It is estimated to infect 20-25 million people every year and can affect people of all ages, but is particularly common in young children. The disease is spread through contaminated food and water, and efforts to improve water quality, sanitation and hygiene will likely go a long way to reducing the global burden of disease. Unfortunately, improving access to clean water and sanitation improvements is very costly and difficult to implement on a large scale. Vaccination against typhoid fever is likely to be a cost-effective way of reducing the global disease burden. There are two vaccines currently available against typhoid fever. Whilst these vaccines provide some protection against disease (in the region of 50-70%) these vaccines are less effective in young children, who are the population group at highest risk of disease. In order to develop a new generation of typhoid vaccines it is important to have a more complete understanding of how the bacterium causes disease. In this study, the investigators are aiming to understand more about the Salmonella Typhi bacteria and how it causes disease. In particular, the investigators aim to study the importance of a toxin produced by the typhoid bacteria, called the typhoid toxin. The typhoid toxin has only recently been discovered. It is made only by the typhoid bacteria and closely related bacteria, such as paratyphoid. From studies done in the laboratory, there is evidence that the typhoid toxin is important in causing typhoid disease. It is thought that the typhoid toxin might be important in causing symptoms of typhoid disease, however the exact role of the typhoid toxin during infection in humans hasn't been studied before. Studying this might impact on the design new vaccines against typhoid. In this study, the investigators will be undertaking a 'challenge' with two strains of the typhoid bacteria (Salmonella Typhi). This involves exposing participants to live Salmonella Typhi under defined circumstances, by asking them to swallow a solution that contains the bacteria. After the challenge the investigators closely monitor participants for a period of at least two weeks and the investigators will then treat participants with antibiotics as soon as they are diagnosed with typhoid disease. The investigators are interested in comparing the response to challenge between two strains of the typhoid bacteria that differ in the production of the typhoid toxin. This process has been undertaken by participants in previous Oxford Vaccine Group studies since 2011.
To develop a rapid, sensitive, and inexpensive diagnostic method, as well as more efficacious vaccine, for countries where typhoid fever remains a major public health burden.
This is a Phase I, Randomized, observer-blinded, age de-escalating study. The study objectives are: 1. To evaluate the safety of 25 μg of Vi-DT typhoid conjugate vaccine administered at 0 and 4 weeks. 2. To assess the immunogenicity of 25 μg of Vi-DT typhoid conjugate vaccine administered at 0 and 4 weeks. 3. To compare the safety and immunogenicity of Vi-DT and Vi-Polysaccharide typhoid vaccines.