Pertussis overview: Difference between revisions
No edit summary |
No edit summary |
||
| Line 16: | Line 16: | ||
==Causes== | ==Causes== | ||
[[Pertussis]] is caused by Bordetella pertussis or Bordetella parapertussis, a [[gram-negative]] [[coccobacillus]]. | [[Pertussis]] is caused by Bordetella pertussis or Bordetella parapertussis, a [[gram-negative]] [[coccobacillus]]. | ||
==Differentiating Pertussis from other diseases== | |||
Pertussis is often misdiagnosed due to early-stage symptoms typically manifesting in other infectious and non infectious causes of cough, such as the Common cold. The greater duration and severity of symptoms, particularly the severely violent coughing fits, make Pertussis clinically distinct. | |||
==Epidemiology and Demographics== | ==Epidemiology and Demographics== | ||
This disease results in high morbidity and mortality in many countries every year. Pertussis causes 20-40 million deaths worldwide, most of which occur in Africa and Southeast Asia. | This disease results in high morbidity and mortality in many countries every year. Pertussis causes 20-40 million deaths worldwide, most of which occur in Africa and Southeast Asia. | ||
==Risk Factors== | ==Risk Factors== | ||
Revision as of 20:25, 6 January 2016
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Associate Editor(s)-in-Chief: Luke Rusowicz-Orazem, B.S.
|
Pertussis Microchapters |
|
Diagnosis |
|---|
|
Treatment |
|
Case Studies |
|
Pertussis overview On the Web |
|
American Roentgen Ray Society Images of Pertussis overview |
Overview
Pertussis, also known as whooping cough, is a highly contagious disease caused by the bacterium Bordetella pertussis. The name is derived from a characteristic severe hacking cough, followed by a high-pitched intake of breath with a "whoop" sound. A similar, milder disease is caused by B. parapertussis.[1] Worldwide, there are 30–50 million pertussis cases and approximately 300,000 deaths per year.
Despite generally high coverage with the DTP and DTaP vaccines, pertussis is one of the leading causes of vaccine-preventable deaths world-wide. The majority of deaths occur in young infants who are either unvaccinated or incompletely vaccinated; three doses of the vaccine are necessary for complete protection against pertussis. Ninety percent of all cases occur in the developing world. However, in the winter of 2006, a New York school district suffered a large pertussis outbreak with greater than thirteen falling victim to the infection. In the fall of 2006, a pertussis outbreak struck New Trier High School, a public school in Winnetka, Illinois, with twenty-four high school students catching the disease. In response, the Cook County Department of Public Health provided the vaccine, free of charge, to eligible students.
Historical Perspective
Pertussis was recognizably described as early as 1578 by Guillaume de Baillou (1538-1616), but earlier reports date back at least to the 12th century.[2] B. pertussis was isolated in pure culture in 1906 by Jules Bordet and Octave Gengou, who also developed the first serology and vaccine. The complete B. pertussis genome of 4,086,186 base pairs was sequenced in 2002.
Pathophysiology
Infection occurs through direct contact with the aerosolized mucus of infected persons, usually during coughing and sneezing. The bacterium adheres to the ciliated epithelium of the nasopharynx, and proliferates in the lower respiratory system. In a small number of cases, the bacteria may move further to the pulmonary alveoli, causing Bordatella pneumonia. The bacteria does not however cross the respiratory epithelium to the bloodstream, and therefore sepsis is not seen.
Causes
Pertussis is caused by Bordetella pertussis or Bordetella parapertussis, a gram-negative coccobacillus.
Differentiating Pertussis from other diseases
Pertussis is often misdiagnosed due to early-stage symptoms typically manifesting in other infectious and non infectious causes of cough, such as the Common cold. The greater duration and severity of symptoms, particularly the severely violent coughing fits, make Pertussis clinically distinct.
Epidemiology and Demographics
This disease results in high morbidity and mortality in many countries every year. Pertussis causes 20-40 million deaths worldwide, most of which occur in Africa and Southeast Asia.
Risk Factors
Children who are too young to be fully vaccinated and those who have not completed the primary vaccination series are at highest risk for severe illness. Like measles, pertussis is highly contagious with up to 90% of susceptible household contacts developing clinical disease following exposure to an index case. Adolescents and adults become susceptible when immunity wanes.
Screening
Bordetella pertussis adenylate cyclase toxin can be used as a screening tool.[3]
Diagnosis
History and Symptoms
After a two day incubation period, pertussis in infants and young children is characterized initially by mild respiratory infection symptoms such as cough, sneezing, and runny nose (catarrhal stage). After one to two weeks, the cough changes character, with paroxysms of coughing followed by an inspiratory "whooping" sound (paroxysmal stage). Coughing fits may be followed by vomiting due to the sheer violence of the fit. In severe cases, the vomiting induced by coughing fits can lead to malnutrition. The fits that do occur on their own can also be triggered by yawning, stretching, laughing, or yelling. Coughing fits gradually diminish over one to two months during the convalescent stage.
Physical Examination
Physical examination adds less to the diagnosis. Conjunctival hemorrhage may be noticed due to intense coughing.
Treatment
Medical Therapy
Treatment with macrolide antibiotic shortens the duration of infection. If macrolides are ineffective co-trimoxazole is administered.
Primary Prevention
Childhood vaccination is highly effective in preventing pertussis. Routine childhood vaccination in the United States is performed with the DTaP vaccine (acellular pertussis vaccine combined with tetanus and diphtheria toxoids).
References
- ↑ Finger H, von Koenig CHW (1996). Bordetella–Clinical Manifestations. In: Barron's Medical Microbiology (Barron S et al, eds.) (4th ed. ed.). Univ of Texas Medical Branch. ISBN 0-9631172-1-1.
- ↑ Versteegh FGA, Schellekens JFP, Fleer A, Roord JJ. (2005). "Pertussis: a concise historical review including diagnosis, incidence, clinical manifestations and the role of treatment and vaccination in management". Rev Med Microbiol. 16 (3): 79–89.
- ↑ Dautin N, Karimova G, Ladant D (2002). "Bordetella pertussis adenylate cyclase toxin: a versatile screening tool". Toxicon. 40 (10): 1383–7. PMID 12368108. Unknown parameter
|month=ignored (help)