Typhoid fever, also known as typhoid, is a disease caused by Salmonella serotype Typhi bacteria. Symptoms vary from mild to severe, and usually begin six to 30 days after exposure. Often there is a gradual onset of a high fever over several days. This is commonly accompanied by weakness, abdominal pain, constipation, headaches, and mild vomiting. Some people develop a skin rash with rose colored spots. In severe cases, people may experience confusion. Without treatment, symptoms may last weeks or months. Diarrhea may be severe, but is uncommon. Other people may carry it without being affected, but are still contagious. Typhoid fever is a type of enteric fever, along with paratyphoid fever. S. enterica Typhi is believed to infect and replicate only within humans.
Salmonella is a genus of rod-shaped (bacillus) gram-negative bacteria of the family Enterobacteriaceae. The two known species of Salmonella are Salmonella enterica and Salmonella bongori. S. enterica is the type species and is further divided into six subspecies that include over 2,600 serotypes. Salmonella was named after Daniel Elmer Salmon (1850–1914), an American veterinary surgeon.
Salmonella enterica is a rod-headed, flagellate, facultative anaerobic, Gram-negative bacterium and a species of the genus Salmonella. A number of its serovars are serious human pathogens; many of them are serovars of Salmonella enterica subsp. enterica.
The Wellcome Sanger Institute, previously known as The Sanger Centre and Wellcome Trust Sanger Institute, is a non-profit British genomics and genetics research institute, primarily funded by the Wellcome Trust.
Paratyphoid fever, also known simply as paratyphoid, is a bacterial infection caused by one of three types of Salmonella enterica. Symptoms usually begin 6–30 days after exposure and are the same as those of typhoid fever. Often, a gradual onset of a high fever occurs over several days. Weakness, loss of appetite, and headaches also commonly occur. Some people develop a skin rash with rose-colored spots. Without treatment, symptoms may last weeks or months. Other people may carry the bacteria without being affected; however, they are still able to spread the disease to others. Typhoid and paratyphoid are of similar severity. Paratyphoid and typhoid fever are types of enteric fever.
An attenuated vaccine is a vaccine created by reducing the virulence of a pathogen, but still keeping it viable. Attenuation takes an infectious agent and alters it so that it becomes harmless or less virulent. These vaccines contrast to those produced by "killing" the virus.
Pathogenomics is a field which uses high-throughput screening technology and bioinformatics to study encoded microbe resistance, as well as virulence factors (VFs), which enable a microorganism to infect a host and possibly cause disease. This includes studying genomes of pathogens which cannot be cultured outside of a host. In the past, researchers and medical professionals found it difficult to study and understand pathogenic traits of infectious organisms. With newer technology, pathogen genomes can be identified and sequenced in a much shorter time and at a lower cost, thus improving the ability to diagnose, treat, and even predict and prevent pathogenic infections and disease. It has also allowed researchers to better understand genome evolution events - gene loss, gain, duplication, rearrangement - and how those events impact pathogen resistance and ability to cause disease. This influx of information has created a need for bioinformatics tools and databases to analyze and make the vast amounts of data accessible to researchers, and it has raised ethical questions about the wisdom of reconstructing previously extinct and deadly pathogens in order to better understand virulence.
A subunit vaccine is a vaccine that contains purified parts of the pathogen that are antigenic, or necessary to elicit a protective immune response. Subunit vaccine can be made from dissembled viral particles in cell culture or recombinant DNA expression, in which case it is a recombinant subunit vaccine.
Salmonella enterica subsp. enterica is a subspecies of Salmonella enterica, the rod-shaped, flagellated, aerobic, Gram-negative bacterium. Many of the pathogenic serovars of the S. enterica species are in this subspecies, including that responsible for typhoid.
Putative sodium-coupled neutral amino acid transporter 10, also known as solute carrier family 38 member 10, is a protein that in humans is encoded by the SLC38A10 gene.
Salmonella bongori is a pathogenic bacterium belonging to the genus Salmonella, and was earlier known as Salmonella subspecies V or S. enterica subsp. bongori or S. choleraesuis subsp. bongori. It is a Gram-negative, rod-shaped bacterium (bacillus), which causes a gastrointestinal disease called salmonellosis, characterized by cramping and diarrhoea. It is typically considered a microbe of cold-blooded animals, unlike other members of the genus, and is most frequently associated with reptiles.
Julian Parkhill is Professor of Bacterial Evolution in the Department of Veterinary Medicine at the University of Cambridge. He previously served as head of pathogen genomics at the Wellcome Sanger Institute.
Edward Thomas Ryan is an American microbiologist, immunologist, and physician at Harvard University and Massachusetts General Hospital. Ryan served as president of the American Society of Tropical Medicine and Hygiene from 2009 to 2010. Ryan is Professor of Immunology and Infectious Diseases at the Harvard T.H. Chan School of Public Health, Professor of Medicine at Harvard Medical School, and Director of Global Infectious Diseases at the Massachusetts General Hospital. Ryan's research and clinical focus has been on infectious diseases associated with residing in, immigrating from, or traveling through resource-limited areas. Ryan is a Fellow of the American Society of Microbiology, the American Society of Tropical Medicine and Hygiene, the American College of Physicians, and the Infectious Diseases Society of America.
Mark Achtman FRS is Professor of Bacterial Population Genetics at Warwick Medical School, part of the University of Warwick in the UK.
Host-directed therapeutics, also called host targeted therapeutics, act via a host-mediated response to pathogens rather than acting directly on the pathogen, like traditional antibiotics. They can change the local environment in which the pathogen exists to make it less favorable for the pathogen to live and/or grow. With these therapies, pathogen killing, e.g.bactericidal effects, will likely only occur when it is co-delivered with a traditional agent that acts directly on the pathogen, such as an antibiotic, antifungal, or antiparasitic agent. Several antiviral agents are host-directed therapeutics, and simply slow the virus progression rather than kill the virus. Host-directed therapeutics may limit pathogen proliferation, e.g., have bacteriostatic effects. Certain agents also have the ability to reduce bacterial load by enhancing host cell responses even in the absence of traditional antimicrobial agents.
Duncan John Maskell, is a British biochemist, academic, and academic administrator, who specialises in molecular microbiology and bacterial infectious diseases. Since 2018, he has been Vice-Chancellor of the University of Melbourne, Australia. He previously taught at the University of Cambridge, England.
Dipshikha Chakravortty is an Indian microbiologist, molecular pathologist and a professor at the department of Microbiology and Cell Biology at the Indian Institute of Science. Known for her studies on Salmonella and antibacterial resistance, Chakravortty is an elected fellow of the National Academy of Sciences, India, the Indian Academy of Sciences and the Indian National Science Academy. The Department of Biotechnology of the Government of India awarded her the National Bioscience Award for Career Development, one of the highest Indian science awards, for her contributions to biosciences, in 2010.
Santasabuj Das is an Indian medical doctor, molecular immunologist, bioinformatician and a scientist at the National Institute of Cholera and Enteric Diseases, Kolkata. He is known for his studies on the pathogenesis of various types of infections caused by Salmonella in humans and is an elected fellow of the West Bengal Academy of Science and Technology. He is a former Fulbright scholar and a life member of the Probiotic Association of India, the Society of Biological Chemists, India and the Indian Science Congress Association. The Department of Biotechnology of the Government of India awarded him the National Bioscience Award for Career Development, one of the highest Indian science awards, for his contributions to biosciences, in 2011.
Kathryn "Kat" Elizabeth Holt is an Australian computational biologist specializing in infectious disease genomics. She is a professor at Monash University's Department of Infectious Diseases and a professor of Microbial Systems Genomics at the London School of Hygiene & Tropical Medicine (LSHTM). Her current research focuses on investigating the evolution and dissemination of antimicrobial resistance. In 2015, Holt received the L'Oréal-UNESCO International Rising Talent Award.
Melita Alison Gordon is a gastroenterologist who works on invasive gut pathogens and tropical gastrointestinal disease. She leads the Malawi Liverpool Wellcome Trust Salmonella and Enterics Group. Gordon was awarded the British Society of Gastroenterology Sir Francis Avery Jones Research Medal in 2011.
