Health Dictionary Find a Doctor

Paratyphoid fever

For patient information click here

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Synonyms and keywords: Enteric fever.

Overview

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Overview

Paratyphoid fevers are a group of enteric illnesses caused by strains of the bacterium Salmonella paratyphi. There are three species of Salmonellae that cause paratyphoid: Salmonella paratyphi A, S. paratyphi B ( or S. schotmulleri) and S. paratyphi C (S. hirschfeldii). They are transmitted by means of contaminated water or food. Typhoid fever is an acute, life-threatening febrile illness caused by the bacterium Salmonella enterica serotype Typhi. Paratyphoid fever is a similar illness caused by S. Paratyphi A, B, or C. The paratyphoid bears similarities with typhoid fever, but its course is more benign.

Causes

Paratyphoid fever is caused by any of three strains of Salmonella paratyphoid: S. paratyphoid A; S. schottmuelleri (also called S. paratyphoid B); or S. hirschfeldii (also called S. paratyphoid C).[1]

Differentiating Paratyphoid fever from other Diseases

Paratyphoid fever resembles typhoid fever but presents with a more abrupt onset, milder symptoms and a shorter course.

Epidemiology and Demographics

Infections with S. Paratyphi A are common in Africa, they follow a course similar to typhoid but rose spots are more abundant and larger. Paratyphoid B is more frequent in Europe. Paratyphoid C is a rare infection, generally seen in the Far East. An estimated 22 million cases of typhoid fever and 200,000 related deaths occur worldwide each year; an additional 6 million cases of paratyphoid fever are estimated to occur annually. Approximately 300 cases of typhoid fever and 150 cases of paratyphoid fever are reported each year in the United States, most of which are in recent travelers.

Risk Factors

Paratyphoid fever can occur in any age group as it is food and water borne. Humans are the only source of these bacteria; no animal or environmental reservoirs have been identified. Typhoid and paratyphoid fever are most often acquired through consumption of water or food that has been contaminated by feces of an acutely infected or convalescent person or a chronic, asymptomatic carrier. Transmission through sexual contact, especially among men who have sex with men, has rarely been documented. The risk of paratyphoid fever is also increasing among travelers to southern and Southeast Asia. Travelers to southern Asia are at highest risk for infections that are nalidixic acid–resistant or multidrug-resistant (resistant to ampicillin, chloramphenicol, and trimethoprim-sulfamethoxazole). Travelers who are visiting friends and relatives (VFRs) are at increased risk. Although the risk of acquiring typhoid or paratyphoid fever increases with the duration of stay, travelers have acquired typhoid fever even during visits <1 week to countries where the disease is endemic.

Natural History, Complications and Prognosis

The serious complications of paratyphoid fever generally occur after 2–3 weeks of illness and may include intestinal hemorrhage or perforation, which can be life threatening. Those diagnosed with Type A of the bacteria strain rarely die from it (in rare cases of severe intestinal complications). With proper testing and diagnosis, the mortality rate falls to less than 1%.

Diagnosis

Physical Examination

In paratyphoid fever, liver and spleen enlargement can be seen.

Laboratory Findings

A single blood culture is positive in only half the cases. Stool culture is not usually positive during the acute phase of the disease. Bone marrow culture increases the diagnostic yield to about 80% of cases. The Widal test is an old serologic assay for detecting IgM and IgG to the O and H antigens of salmonella. The test is unreliable but is widely used in developing countries because of its low cost. Newer serologic assays are somewhat more sensitive and specific than the Widal test but are infrequently available. Because there is no definitive serologic test for typhoid or paratyphoid fever, the diagnosis often has to be made clinically. Paratyphoid B is diagnosed by the isolation of the agent in blood or stool and demonstration of antibodies anti BH in the Widal test. Antibodies to paratyphoid C are not usually tested and the diagnosis is made with blood cultures.

Treatment

Medical Therapy

Empiric treatment in most parts of the world would use a fluoroquinolone, most often ciprofloxacin. However, resistance to fluoroquinolones is highest in the Indian subcontinent and increasing in other areas. Injectable third-generation cephalosporins are often the empiric drug of choice when the possibility of fluoroquinolone resistance is high. Patients treated with an appropriate antibiotic may still require 3–5 days to defervesce completely, although the height of the fever decreases each day. Patients may actually feel worse when the fever starts to go away. If fever does not subside within 5 days, alternative antimicrobial agents or other foci of infection should be considered. Control requires treatment of antibiotics and vaccines prescribed by a doctor. Major control treatments for Paratyphoid fever include ciprofloxacin for ten days or ceftriaxone/ cefotaxime for 14 days or aziththromycin.

Paratyphoid B responds well to chloramphenicol or co-trimoxazole.

Chloramphenicol therapy is generally effective for Paratyphoid C.

Primary Prevention

Children and adults should be carefully educated about personal hygiene. This would include careful hand washing after defecation and sexual contact, before preparing or eating food, and especially the sanitary disposal of feces. Food handlers should be educated in personal hygiene prior to handling food or utensils and equipment. Infected individuals should be advised to avoid food preparation.

Those who travel to countries with poor sanitation should receive a typhoid vaccine, which provides protection against typhoid fever but not paratyphoid Infection A, B or C, prior to departure. Sexually active people should be educated about the risks of sexual practices that permit fecal-oral contact. Owners of tropical fish should ensure scrupulous cleaning of aquariums to eliminate potential S. Paratyphi B organisms.

Secondary Prevention

Exclusion from work and social activities should be considered for symptomatic, and asymptomatic people who are food handlers, healthcare/daycare staff who are involved in patient care and/ or child care, children attending unsanitary daycare centers, and older children who are unable to implement good standards of personal hygiene. The exclusion applies until two consecutive stool specimens are taken from the infected patient and are reported negative.

References

  1. Frey, J. Rebecca. Paratyphoid Fever 1999. Encyclopedia of Medicine. 28 Oct 2008<http://findarticles.com/p/articles/mi_g2601/is_/ai_2601001024>

Template:WH Template:WS

Historical Perspective

Please help WikiDoc by adding content here. It’s easy! Click here to learn about editing.

References

Template:WH Template:WS

Classification

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Please help WikiDoc by adding more content here. It’s easy! Click here to learn about editing.

Classification

  • Paratyphoid A
  • Paratyphoid B – Paratyphoid B is more frequent in Europe. It can present as a typhoid like illness, as a severe gastroenteritis or with features of both. Herpes labialis, rare in true typhoid fever, is frequently seen in Paratyphoid B.
  • Parathyroid C – Paratyphoid C is a rare infection, generally seen in the Far East. It presents as a septicemia with metastatic abscesses. Cholecystitis is possible in the course of the disease.

References

Template:WH Template:WS

Pathophysiology

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Please help WikiDoc by adding more content here. It’s easy! Click here to learn about editing.

Pathophysiology

Paratyphoid fever starts when the bacterium Salmonella typhi is passed from another person due to bad hygiene such as lack of washing hands after using the restroom. Eventually the bacteria passes down to bowel, then penetrating the intestinal mucosa (lining) to the underlying tissue. If the immune system is unable to stop the infection here, bacteria multiplies and spread to the bloodstream, after which the first signs of disease are observed in the form of fever. Bacteria can penetrate further to the bone marrow, liver and bile ducts, and are excreted into the bowel contents. In the second phase of the disease, bacteria penetrates the immune tissue of the small intestine, and the initial symptoms of small-bowel movements begin.

Salmonella typhi can specifically only attack humans, so the infection nearly always comes from contact another human, either an ill person or a healthy carrier of the bacterium. The bacterium is passed on with water and foods and can withstand both drying and refrigeration but by keeping food refrigerated correctly this minimizes the production of the bacterium significantly.

Carriers

Humans and, occasionally, domestic animals are the carriers of paratyphoid fever. Members of the same family can be transient or permanent carriers. In most parts of the world, short-term fecal carriers are more common than urinary carriers.

It is possible to continue to shed Salmonella paratyphi for up to one year and, during this phase, a person is considered to be a carrier. The chronic carrier state may follow acute illness, mild or even sub clinical infections. Chronic carriers are most often women who were infected in their middle age.

References


Template:WikiDoc Sources

Causes

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Please help WikiDoc by adding more content here. It’s easy! Click here to learn about editing.

Overview

Paratyphoid fever is caused by any of three strains of Salmonella paratyphoid: S. paratyphoid A; S. schottmuelleri (also called S. paratyphoid B); or S. hirschfeldii (also called S. paratyphoid C).[1]

References

  1. Frey, J. Rebecca. Paratyphoid Fever 1999. Encyclopedia of Medicine. 28 Oct 2008 <http://findarticles.com/p/articles/mi_g2601/is_/ai_2601001024>


Template:WikiDoc Sources

Differentiating Paratyphoid fever from other Diseases

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Please help WikiDoc by adding more content here. It’s easy! Click here to learn about editing.

Overview

Paratyphoid fever resembles Typhoid Fever but presents with a more abrupt onset, milder symptoms and a shorter course.

References

Template:WH Template:WS

Epidemiology and Demographics

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Overview

Infections with S. Paratyphi A are common in Africa, they follow a course similar to typhoid but rose spots are more abundant and larger. Paratyphoid B is more frequent in Europe. Paratyphoid C is a rare infection, generally seen in the Far East. An estimated 22 million cases of typhoid fever and 200,000 related deaths occur worldwide each year; an additional 6 million cases of paratyphoid fever are estimated to occur annually. Approximately 300 cases of typhoid fever and 150 cases of paratyphoid fever are reported each year in the United States, most of which are in recent travelers.

Epidemiology and Demographics

Developed Countries

Approximately 300 cases of typhoid fever and 150 cases of paratyphoid fever are reported each year in the United States, most of which are in recent travelers. Paratyphoid B is more frequent in Europe. Paratyphoid C is a rare infection, generally seen in the Far East.

Developing Countries

Infections with S. Paratyphi A are common in Africa, they follow a course similar to typhoid but rose spots are more abundant and larger. The risk of typhoid fever is highest for travelers to southern Asia (6–30 times higher than for all other destinations). Other areas of risk include East and Southeast Asia, Africa, the Caribbean, and South America. Factors outside the household like unclean food from street vendors and flooding help distribute the disease from person to person.[1] Because of poverty and poor hygiene and sanitary conditions the disease is more common in less-industrialized countries, principally owing to the problem of unsafe drinking-water, inadequate sewage disposal and flooding.[2] Occasionally causing epidemics, paratyphoid fever is found in large parts of Asia, Africa, Central and South America. Many of those infected get the disease in Asian countries. There are about 16 million cases a year, which result in about 25,000 deaths worldwide.[3]

References

  1. Bhan MK, Bahl R, Bhatnagar S (2005). “Typhoid and paratyphoid fever”. Lancet. 366 (9487): 749–62. doi:10.1016/S0140-6736(05)67181-4. PMID 16125594.
  2. “Water-related Diseases.” Communicable Diseases 2001. World Health Organization. 31 Oct 2008 <http://www.who.int/water_sanitation_health/diseases/typhoid/en/>.
  3. Rubin, Raphael., David S. Strayer., Emanuel Rubin., Jay M. McDonald. Rubin’s Pathology. 5th ed. 2007


Template:WikiDoc Sources

Risk Factors

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Overview

Infections with S. Paratyphi A are common in Africa, they follow a course similar to typhoid but rose spots are more abundant and larger. Paratyphoid B is more frequent in Europe. Paratyphoid C is a rare infection, generally seen in the Far East. An estimated 22 million cases of typhoid fever and 200,000 related deaths occur worldwide each year; an additional 6 million cases of paratyphoid fever are estimated to occur annually. Approximately 300 cases of typhoid fever and 150 cases of paratyphoid fever are reported each year in the United States, most of which are in recent travelers.

Epidemiology and Demographics

Developed Countries

Approximately 300 cases of typhoid fever and 150 cases of paratyphoid fever are reported each year in the United States, most of which are in recent travelers. Paratyphoid B is more frequent in Europe. Paratyphoid C is a rare infection, generally seen in the Far East.

Developing Countries

Infections with S. Paratyphi A are common in Africa, they follow a course similar to typhoid but rose spots are more abundant and larger. The risk of typhoid fever is highest for travelers to southern Asia (6–30 times higher than for all other destinations). Other areas of risk include East and Southeast Asia, Africa, the Caribbean, and South America. Factors outside the household like unclean food from street vendors and flooding help distribute the disease from person to person.[1] Because of poverty and poor hygiene and sanitary conditions the disease is more common in less-industrialized countries, principally owing to the problem of unsafe drinking-water, inadequate sewage disposal and flooding.[2] Occasionally causing epidemics, paratyphoid fever is found in large parts of Asia, Africa, Central and South America. Many of those infected get the disease in Asian countries. There are about 16 million cases a year, which result in about 25,000 deaths worldwide.[3]

References

  1. Bhan MK, Bahl R, Bhatnagar S (2005). “Typhoid and paratyphoid fever”. Lancet. 366 (9487): 749–62. doi:10.1016/S0140-6736(05)67181-4. PMID 16125594.
  2. “Water-related Diseases.” Communicable Diseases 2001. World Health Organization. 31 Oct 2008 <http://www.who.int/water_sanitation_health/diseases/typhoid/en/>.
  3. Rubin, Raphael., David S. Strayer., Emanuel Rubin., Jay M. McDonald. Rubin’s Pathology. 5th ed. 2007


Template:WikiDoc Sources

Natural History, Complications and Prognosis

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Please help WikiDoc by adding more content here. It’s easy! Click here to learn about editing.

Overview

The serious complications of paratyphoid fever generally occur after 2–3 weeks of illness and may include intestinal hemorrhage or perforation, which can be life threatening. Those diagnosed with Type A of the bacteria strain rarely die from it (in rare cases of severe intestinal complications). With proper testing and diagnosis, the mortality rate falls to less than 1%.

References


Template:WikiDoc Sources

Diagnosis

History and Symptoms | Physical Examination | Laboratory Findings | CT | Ultrasound | Other Imaging Findings | Other Diagnostic Studies

Treatment

Treatment

Medical Therapy | Surgery | Primary Prevention | Secondary Prevention | Cost-Effectiveness of Therapy | Future or Investigational Therapies

Case Studies

Case Studies

Case #1

Related Chapters

Template:Bacterial diseases bg:Паратиф de:Paratyphus


Template:WikiDoc Sources

Looking for the patient version?

Back to the patient-friendly article

© 2026 MyEClinic – IFTM Institut für Telematik in der Medizin GmbH