typhoid fever

typhoid fever
Name	Typhoid fever
Symptoms	Fever, headache, abdominal pain, constipation, diarrhea
Complications	Intestinal perforation, hemorrhage, encephalopathy
Onset	1–3 weeks after exposure
Causes	Infection by Salmonella enterica serovar Typhi
Diagnosis	Blood culture, stool culture, bone marrow culture, Widal test
Prevention	Vaccination, safe water, improved sanitation, hand hygiene
Treatment	Antibiotics (azithromycin, ceftriaxone, fluoroquinolones), fluid replacement
Frequency	Hundreds of thousands to millions of cases annually

typhoid fever Typhoid fever is a systemic infectious disease characterized by prolonged high fever, abdominal symptoms, and systemic complications caused by a bacterial pathogen. It remains an important cause of morbidity and mortality in many regions despite the availability of vaccines and antimicrobial therapies. Historically, typhoid has influenced public health reforms and appears in accounts of military campaigns, colonial administration, and urban sanitation efforts.

Signs and symptoms

Initial presentation commonly includes sustained high fever, headache, malaise, and abdominal discomfort. Prominent historical and clinical descriptions appear in accounts associated with Crimean War, American Civil War, World War I, World War II, and Vietnam War, where febrile illnesses affected troop readiness. Patients may develop relative bradycardia, coated tongue, and hepatosplenomegaly; complications such as intestinal perforation or massive gastrointestinal bleeding have been documented in literature concerning Florence Nightingale and 19th-century hospital reform narratives. Neuropsychiatric manifestations including delirium, stupor, and "typhoid state" are noted in texts related to Sigmund Freud, Carl Jung, and contemporaneous clinical manuals. Chronic carriage, including asymptomatic gallbladder carriage associated historically with figures discussed in biographies of Typhoid Mary and analyses referencing Mary Mallon, can lead to prolonged bacterial shedding and outbreaks linked to food handlers and municipal outbreaks such as those recounted in histories of Chicago, New York City, and London.

Cause and pathophysiology

The disease is caused by infection with Salmonella enterica serovar Typhi, a Gram-negative bacillus described in bacteriological accounts connected to researchers like Karl Joseph Eberth and Camillo Golgi in microbiology histories. Pathogen entry commonly occurs via ingestion of contaminated water or food, events often tied to failures in infrastructure documented in investigations involving Panama Canal construction, Pittsburgh public health reforms, and colonial reports from British India. After intestinal invasion, the organism traverses M cells of Peyer patches, replicates within macrophages, and disseminates via the reticuloendothelial system to liver, spleen, bone marrow, and gallbladder; these processes are discussed in cellular immunology treatises referencing work at institutions such as Pasteur Institute, Robert Koch Institute, and Johns Hopkins University. Chronic carriage in the biliary tract is associated with gallstones and biofilm formation, topics featured in surgical histories involving William Halsted and case series from major hospitals like Mayo Clinic.

Diagnosis

Definitive diagnosis requires isolation of the organism from blood, stool, urine, or bone marrow cultures, methods refined in laboratories associated with Centers for Disease Control and Prevention, WHO, and national reference laboratories such as Public Health England. Blood cultures are most sensitive early in illness, while bone marrow culture provides higher yield in treated cases, procedures described in clinical microbiology texts from Harvard Medical School and Oxford University Clinical School. Serologic tests such as the Widal test remain in epidemiologic literature concerning outbreaks in regions documented by Médecins Sans Frontières and national ministries of health, though they lack specificity compared with culture or molecular assays. Molecular diagnostics, including PCR assays, are topics in publications from Wellcome Trust–funded research and genomic investigations by groups at Broad Institute and Wellcome Sanger Institute.

Prevention and vaccination

Prevention strategies emphasize safe water, sanitation, and hygiene interventions promoted by organizations like World Health Organization, UNICEF, and Bill & Melinda Gates Foundation. Vaccination options include oral live-attenuated and injectable Vi capsular polysaccharide vaccines, developed through research collaborations involving National Institutes of Health, Serum Institute of India, and vaccine manufacturers such as GlaxoSmithKline and Bharat Biotech. Mass immunization campaigns and endemic control efforts are chronicled in public health responses in Pakistan, Bangladesh, Nepal, and urban initiatives in Lagos and Dhaka. Policy discussions on vaccine deployment and antimicrobial stewardship have been addressed at forums hosted by Gavi, the Vaccine Alliance and global health meetings at World Health Assembly.

Treatment

Effective antimicrobial therapy reduces mortality; recommended agents vary by region due to resistance patterns tracked by surveillance networks like Global Antimicrobial Resistance Surveillance System and reports from European Centre for Disease Prevention and Control. Empiric regimens have included third-generation cephalosporins (e.g., ceftriaxone), macrolides (e.g., azithromycin), and fluoroquinolones, with resistant strains prompting reassessment of guidelines by panels at Infectious Diseases Society of America and British Infection Association. Supportive care, including fluid resuscitation and management of complications such as intestinal perforation, draws on surgical protocols found in literature from Royal College of Surgeons and trauma centers like Guy's and St Thomas' NHS Foundation Trust. Chronic carriers may require cholecystectomy or prolonged antibiotic courses, interventions described in surgical and infectious disease case series from institutions such as John Radcliffe Hospital and Cleveland Clinic.

Epidemiology and public health impact

Global burden estimates published by agencies including World Health Organization and Institute for Health Metrics and Evaluation indicate substantial incidence in parts of South Asia, Southeast Asia, Sub-Saharan Africa, and areas with limited water infrastructure, with notable outbreaks reported in settings like refugee camps documented by International Committee of the Red Cross and UNHCR. Historical analyses link typhoid to shifts in urban planning and sanitation reform influenced by figures such as Edwin Chadwick and events like the Great Stink of London. Surveillance, vaccine introduction, and improvements in sanitation have reduced incidence in high-income settings including United States and Western Europe, while antimicrobial resistance emergence—documented in genomic studies at Sanger Institute and reports from CDC—poses ongoing challenges for global health security discussed at G20 health summits and in policy briefs by World Bank and The Lancet-affiliated commissions.

Category:Infectious diseases