Bordetella pertussis: Difference between revisions

style="background:#Template:Taxobox colour;"\|Bordetella pertussis
	File:Bordetella pertussis.jpg;
style="background:#Template:Taxobox colour;" \| Scientific classification
Kingdom:	Bacteria;
Phylum:	Proteobacteria;
Class:	Beta Proteobacteria;
Order:	Burkholderiales;
Family:	Alcaligenaceae;
Genus:	Bordetella;
Species:	B. pertussis;
Binomial name
	Bordetella pertussis; (Bergey et al. 1923); Moreno-López 1952

VisualWikitext

Revision as of 15:10, 6 August 2015

This page is about microbiologic aspects of the organism(s). For clinical aspects of the disease, see Whooping Cough, or Pertussis.

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: João André Alves Silva, M.D. [2]

Overview

Bordetella pertussis is a Gram-negative, aerobic coccobacillus capsulate of the genus Bordetella, and the causative agent of pertussis or whooping cough. Unlike B. bronchiseptica, B. pertussis is not motile. Its virulence factors include pertussis toxin, filamentous hæmagglutinin, pertactin, fimbria, and tracheal cytotoxin.

A zoonotic reservoir for B. pertussis does not appear to exist; humans are its only known host, which means universal vaccination could potentially eradicate the disease.^{[citation needed]}

The bacterium is spread by airborne droplets; its incubation period is 7 to 14 days.

Pertussis

Pertussis (or whooping cough) is an infection of the respiratory system characterized by a “whooping” sound when the person breathes in. In the US, it killed between 10,000 and 20,000 people per year before a vaccine was available. Vaccination has transformed this; between 1985 and 1988, fewer than 100 children died from pertussis. Worldwide in 2000, according to the WHO, around 39 million people were infected annually and about 297,000 died. A graph is available showing the dramatic effect of introducing vaccination in England.^[1] B. pertussis infects its host by colonizing lung epithelial cells. The bacterium contains a surface protein, filamentous haemagglutinin adhesin, which binds to the sulfatides found on cilia of epithelial cells. Once anchored, the bacterium produces tracheal cytotoxin, which stops the cilia from beating. This prevents the cilia from clearing debris from the lungs, so the body responds by sending the host into a coughing fit. These coughs expel some bacteria into the air, which are free to infect other hosts.

B. pertussis has the ability to inhibit the function of the host's immune system. The toxin, known as pertussis toxin (or PTx), inhibits G protein coupling that regulates an adenylate cyclase-mediated conversion of ATP to cyclic AMP. The end result is phagocytes convert too much ATP to cyclic AMP, which can cause disturbances in cellular signaling mechanisms, and prevent phagocytes from correctly responding to an infection. PTx, formerly known as lymphocytosis-promoting factor, causes a decrease in the entry of lymphocytes into lymph nodes, which can lead to a condition known as lymphocytosis, with a complete lymphocyte count of over 4000/μl in adults or over 8000/μl in children.

The infection occurs mostly in children under the age of one when they are unimmunized, or children with faded immunity, normally around the ages 11 through 18. The signs and symptoms are similar to a common cold: runny nose, sneezing, mild cough, and low-grade fever. The patient becomes most contagious during the catarrhal stage of infection, normally two weeks after the coughing begins. It may become airborne when the person coughs, sneezes, or laughs. Pertussis vaccine is part of the diphtheria, tetanus, and acellular pertussis (DTaP) immunization. The paroxysmal cough precedes a crowing inspiratory sound characteristic of pertussis. After a spell, the patient might make a “whooping” sound when breathing in, or may vomit. Adults have milder symptoms, such as prolonged coughing without the “whoop”. Infants less than six months also may not have the typical whoop. A coughing spell may last a minute or more, producing cyanosis, apnoea, and seizures. However, when not in a coughing fit, the patient does not experience trouble breathing. This is because B. pertussis inhibits the immune response, so very little mucus is generated in the lungs. A prolonged cough may be irritating and sometimes a disabling cough may go undiagnosed in adults for many months.

Diagnosis

A nasopharyngeal or an oropharynx swab is sent to the bacteriology laboratory for Gram stain (Gram-negative, coccobacilli, diplococci arrangement), growth on Bordet-Gengou agar or BCYE plate with added cephalosporin to select for the organism, which shows mercury-drop-like colonies.

Several diagnostic tests are available, especially ELISA kits. These are designed to detect FHA and/or PT antibodies of the following classes: IgG, IgA, IgM. Some kits use a combination of antigens which will lead to a higher sensitivity, but might also make the interpretation of the results harder since one cannot know which antibody has been detected. Also, a new rapid molecular test is available, real-time PCR, based on the so-called FilmArray technology . This test takes about one hour and detects about 15–17 viruses and bacteria, including B. pertussis.

The organism is oxidase positive, but urease, nitrate reductase, and citrate negative. It is also nonmotile.

References

↑ "Whooping Cough (Pertussis)". HPA. Retrieved 2009-04-12.

Ray, C.G., ed. (2004). Sherris Medical Microbiology (4th ed.). McGraw Hill. ISBN 0-8385-8529-9.
Todar, K. (2008). "Bordetella pertussis and Whooping Cough". Online Textbook of Bacteriology. Retrieved December 11, 2009.

External links

"Pertussis". Immunization, Vaccines and Biologicals. World Health Organisation.
Finger, Horst; von Koenig, C.H.W. (1996). "Ch. 31 Bordetella". In Baron, S. Medical Microbiology (4th ed.). University of Texas Medical Branch. ISBN 0-9631172-1-1. NBK7813.
"Bordetella pertussis". ARUP Consult—The Physician's Guide to Laboratory Test Selection and Interpretation.
"Pertussis". United Kingdom Health Protection Agency.
Centers for Disease Control and Prevention (2012). "Pertussis". In Atkinson, W.; Wolfe, S.; Hamborsky, J. Epidemiology and Prevention of Vaccine-Preventable Diseases: The Pink Book (12th ed.). Public Health Foundation.
"Bordetella pertussis". NCBI Taxonomy Browser. 520.

[1] "Whooping Cough (Pertussis)". HPA. Retrieved 2009-04-12.

[1]

@@ Line 1: / Line 1: @@
+__NOTOC__
+{{About0|Whooping Cough, or Pertussis}}
+{{CMG}}; {{AE}} {{JS}}
 {{Taxobox
-| color = lightgrey
+| | name = ''Bordetella pertussis''
-| name = ''Bordetella pertussis''
+| image = Bordetella_pertussis.jpg
-| image = Bordetella_pertussis_01.jpg
 | image_width = 240px
 | image_caption =
-| regnum = [[Bacterium|Bacteria]]
+| regnum = [[Bacteria]]
 | phylum = [[Proteobacteria]]
 | classis = [[Beta Proteobacteria]]
@@ Line 15: / Line 17: @@
 | binomial_authority = (Bergey ''et al.'' 1923)<br>Moreno-López 1952
 }}
-'''''Bordetella pertussis''''' is a [[Gram-negative]] [[bacterium]] of the genus ''[[Bordetella]]'', and the causative agent of [[pertussis]] or whooping cough. Unlike ''[[Bordetella bronchiseptica|B. bronchiseptica]]'', ''B. pertussis'' is non-[[motile]].
+==Overview==
-There does not appear to be a [[zoonotic]] reservoir for ''B. pertussis''&mdash;humans are its only [[Host (biology)|host]].
+'''''Bordetella pertussis''''' is a [[Gram-negative]], [[Aerobic organism|aerobic]] [[coccobacillus]] [[Bacterial capsule|capsulate]] of the genus ''[[Bordetella]]'', and the causative agent of [[pertussis]] or whooping cough. Unlike ''[[Bordetella bronchiseptica|B. bronchiseptica]]'', ''B. pertussis'' is not [[motile]]. Its virulence factors include [[pertussis toxin]], [[Filamentous haemagglutinin adhesin|filamentous hæmagglutinin]], [[pertactin]], [[Fimbria (bacteriology)|fimbria]], and [[tracheal cytotoxin]].
-The bacterium is spread by coughing and by nasal drops.  The incubation period is 7-14 days.
+A [[zoonotic]] reservoir for ''B. pertussis'' does not appear to exist; humans are its only known [[Host (biology)|host]], which means universal vaccination could potentially eradicate the disease.{{fact|date=April 2015}}
-==Features==
+The bacterium is spread by airborne droplets; its incubation period is 7 to 14 days.
-Whooping Cough, or Pertussis, is an infection of the respiratory system and characterized by a “whooping” sound when the person breathes in. In the US it killed 5,000 to 10,000 people per year before a vaccine was available. Vaccination has transformed this and between 1985-88 less than 100 children died from pertussis. Worldwide in 2000, according to the WHO, around 39 million people were infected annually and about 297,000 died. A graph is available showing the dramatic effect of introducing [http://www.hpa.org.uk/infections/topics_az/whoopingcough/gen_info.htm vaccination in England].
+==Pertussis==
+[[Pertussis]] (or whooping cough) is an infection of the [[respiratory system]] characterized by a “whooping” sound when the person breathes in. In the US, it killed between 10,000 and 20,000 people per year before a vaccine was available. [[Vaccination]] has transformed this; between 1985 and 1988, fewer than 100 children died from pertussis. Worldwide in 2000, according to the WHO, around 39 million people were infected annually and about 297,000 died. A graph is available showing the dramatic effect of introducing vaccination in England.<ref>{{cite web |url=http://www.hpa.org.uk/Topics/InfectiousDiseases/InfectionsAZ/WhoopingCough/EpidemiologicalData/whoo45VacCover1940to2008/+ |title=Whooping Cough (Pertussis) |publisher=HPA  |accessdate=2009-04-12}}</ref>
+''B. pertussis'' infects its host by colonizing lung epithelial cells. The bacterium contains a surface protein, [[filamentous haemagglutinin adhesin]], which binds to the [[sulfatide]]s found on cilia of epithelial cells. Once anchored, the bacterium produces tracheal cytotoxin, which stops the cilia from beating. This prevents the cilia from clearing debris from the lungs, so the body responds by sending the host into a coughing fit. These coughs expel some bacteria into the air, which are free to infect other hosts.
-Whooping Cough occurs most with children under the age of one when they are immunized or children with faded immunity, normally around the age 11 through 18. The signs and symptoms are similar to a common cold: runny nose, sneezing, mild cough, and low-grade fever. After a spell, they might make a “whooping” sound when breathing in or vomit. Adults have milder symptoms, like prolonged coughing without the “whoop.” Pertussis is highly contagious and may become airborne when the person coughs, sneezes, or laughs. People infected by this disease are more contagious in the earliest stages of it, normally 2 weeks after the coughing begins. Whooping Cough can be prevented by the Pertussis Vaccine which is part of the DTaP (diphtheria, tetanus, acellular Pertussis) immunization. The paroxysmal cough precedes a crowing inspiratory sound characteristic of pertussis. (Infants less than 6 months may not have the typical whoop.) A coughing spell may last a minute or more, producing cyanosis, apnoea and seizures.
+''B. pertussis'' has the ability to inhibit the function of the host's immune system. The toxin, known as [[pertussis toxin]] (or PTx), inhibits [[G protein]] coupling that regulates an [[adenylate cyclase]]-mediated conversion of [[Adenosine triphosphate|ATP]] to [[cyclic AMP]]. The end result is phagocytes convert too much ATP to cyclic AMP, which can cause disturbances in cellular signaling mechanisms, and prevent phagocytes from correctly responding to an infection. PTx, formerly known as lymphocytosis-promoting factor, causes a decrease in the entry of lymphocytes into lymph nodes, which can lead to a condition known as [[lymphocytosis]], with a complete [[lymphocyte]] count of over 4000/μl in adults or over 8000/μl in children.
+The infection occurs mostly in children under the age of one when they are [[Immunization|unimmunized]], or children with faded [[Immunity (medical)|immunity]], normally around the ages 11 through 18. The signs and symptoms are similar to a [[common cold]]: runny nose, [[sneezing]], mild [[cough]], and low-grade [[fever]]. The patient becomes most contagious during the [[catarrhal]] stage of infection, normally two weeks after the coughing begins. It may become airborne when the person coughs, sneezes, or laughs. [[DPT vaccine|Pertussis vaccine]] is part of the [[diphtheria]], [[tetanus]], and acellular pertussis (DTaP) immunization. The [[paroxysmal]] cough precedes a crowing inspiratory sound characteristic of pertussis. After a spell, the patient might make a “whooping” sound when breathing in, or may vomit. Adults have milder symptoms, such as prolonged coughing without the “whoop”. Infants less than six months also may not have the typical whoop. A coughing spell may last a minute or more, producing [[cyanosis]], [[apnoea]], and [[seizures]]. However, when not in a coughing fit, the patient does not experience trouble breathing. This is because ''B. pertussis'' inhibits the immune response, so very little mucus is generated in the lungs.
 A prolonged cough may be irritating and sometimes a disabling cough may go undiagnosed in adults for many months.
-''Bodetella pertussis'' also produces a lymphocytosis-promoting factor, which causes a decrease in the entry of lymphocytes into lymph nodes.  This can lead to a condition known as lymphocytosis, with a complete lymphocyte count over of 4000/μL in adults or over 8000/μL in children.
+==Diagnosis==
+A nasopharyngeal or an oropharynx swab is sent to the [[bacteriology]] laboratory for [[Gram stain]] (Gram-negative, coccobacilli, diplococci arrangement), growth on [[Bordet-Gengou agar]] or [[Buffered charcoal yeast extract agar|BCYE]] plate with added [[cephalosporin]] to select for the organism, which shows mercury-drop-like colonies.
-==Antimicrobial therapy==
+Several diagnostic tests are available, especially [[ELISA]] kits. These are designed to detect FHA and/or PT antibodies of the following classes: IgG, IgA, IgM.
+Some kits use a combination of antigens which will lead to a higher sensitivity, but might also make the interpretation of the results harder since one cannot know which antibody has been detected. Also, a new rapid molecular test is available, real-time PCR, based on the so-called FilmArray technology . This test takes about one hour and detects about 15–17 viruses and bacteria, including ''B. pertussis''.
-:* 1. '''Whooping cough'''<ref>{{Cite web | title = Recommended Antimicrobial Agents for the Treatment and Postexposure Prophylaxis of Pertussis 2005 CDC Guidelines
+The organism is [[oxidase test|oxidase]] positive, but [[Rapid urease test|urease]], [[nitrate reductase]], and [[citrate]] negative. It is also nonmotile.
- | url = http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5414a1.htm#tab4}}</ref>
-::* 1.1 '''Adults'''
-:::* Preferred regimen (1): [[Azithromycin]] 500 mg PO single dose on day 1 {{then}} 250 mg PO qd on 2-5 days
-:::* Preferred regimen (2): [[Erythromycin]] 2 g/day PO qid for 14 days
-:::* Preferred regimen (3): [[Clarithromycin]] 1 g PO bid for 7 days.
-:::* Alternative regimen (intolerant of macrolides): [[Trimethoprim]] 320 mg/day {{and}} [[Sulfamethoxazole]] 1600 mg/day PO bid for 14 days
-::* 1.2 '''Infants <6 months of age'''
-:::* 1.2.1 '''Infants <1 month'''
-::::* Preferred regimen (1): [[Azithromycin]] 10 mg/kg PO qd for 5 days
-::::* Preferred regimen (2) (if azithromycin unavailable): [[Erythromycin]] 40-50 mg/kg/day PO q6h for 14 days
-::::* Note: TMP-SMX contraindicated for infants aged < 2 months
-:::* 1.2.2 '''Infants of 1-5 months of age'''
-::::* Preferred regimen (1): [[Azithromycin]] 10 mg/kg PO qd for 5 days
-::::* Preferred regimen (2): [[Erythromycin]] 40-50 mg/kg/day PO qid for 14 days
-::::* Preferred regimen (3): [[Clarithromycin]] 15 mg/kg PO bid for 7 days
-::::* Alternative regimen: For infants aged ≥ 2 months [[TMP]] 8 mg/kg q24h {{and}} [[Sulfamethoxazole|SMX]] 40 mg/kg/day PO bid for 14 days
-::* 1.3 '''Infants ≥6 months of age-children'''
-::::* Preferred regimen(1): [[Azithromycin]] 10 mg/kg single dose {{then}} 5 mg/kg (500 mg Maximum) qd for 2-5 days
-::::* Preferred regimen(2): [[Erythromycin]] 40-50 mg/kg PO (2 g daily Maximum) qid for 14 days
-::::* Preferred regimen(3): [[Clarithromycin]] 15 mg/kg PO (1 g daily Maximum) bid for 7 days
-::::* Preferred regimen(4): [[TMP]] 8 mg/kg/day {{and}} [[Sulfamethoxazole|SMX]] 40 mg/kg/day bid for 14 days
-:* 2. '''Post exposure prophylaxis'''<ref>{{Cite web | title = Recommended Antimicrobial Agents for the Treatment and Post exposure Prophylaxis of Pertussis 2005 CDC Guidelines
- | url = http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5414a1.htm#tab4}}</ref>
-::* Preferred regimen: The antibiotic regimens for post exposure prophylaxis are similar to the regimens used for the treatment of pertussis
-::* Note (1):  Post exposure prophylaxis to an asymptomatic contacts within 21 days of onset of cough in the index patient can potentially prevent symptomatic infection
-::* Note (2): Close contacts include persons who have direct contact with respiratory, oral or nasal secretions from a symptomatic patient (eg: cough, sneeze, sharing food, eating utensils, mouth to mouth resuscitation, or performing a medical examination of the mouth, nose, throat.
-::* Note (3): Some close contacts are at high risk for acquiring severe disease following exposure to pertussis. These contacts include infants aged < 1 year , persons with some immunodeficiency conditions, or other underlying medical conditions such as chronic lung disease, respiratory insufficiency and cystic fibrosis.
 ==References==
 {{reflist|2}}
-* {{cite book | author = Ryan KJ; Ray CG (editors) | title = Sherris Medical Microbiology | edition = 4th ed. | publisher = McGraw Hill | year = 2004 | id = ISBN 0-8385-8529-9 }}
+{{refbegin}}
+* {{cite book |editor-last= Ray |editor-first=C.G. | title = Sherris Medical Microbiology | edition = 4th | publisher = McGraw Hill | year = 2004 | isbn = 0-8385-8529-9 }}
+*{{cite web |url=http://www.textbookofbacteriology.net/pertussis.html |title=''Bordetella pertussis'' and Whooping Cough |first=K. |last=Todar |year=2008 |work= Online Textbook of Bacteriology |accessdate=December 11, 2009}}
+{{refend}}
 ==External links==
-*[http://www.who.int/immunization/topics/pertussis/en/index1.html Pertussis] Information from the World Health Organisation
+*{{cite web |title=Pertussis |work=Immunization, Vaccines and Biologicals |publisher=World Health Organisation |url=http://www.who.int/immunization/topics/pertussis/en/index1.html }}
+*{{cite book |first=Horst |last=Finger |first2=C.H.W. |last2=von Koenig |chapter=Ch. 31 Bordetella |chapterurl=http://www.ncbi.nlm.nih.gov/books/NBK7813/ |editor-first=S. |editor-last=Baron |title=Medical Microbiology |publisher=University of Texas Medical Branch |edition=4th |year=1996 |isbn=0-9631172-1-1 |pages= |url=http://www.ncbi.nlm.nih.gov/books/NBK7627/ |id=NBK7813}}
-*[http://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=mmed.chapter.1684 ''Bordetella'' chapter] in Baron's ''Medical Microbiology'' (online text at the [[National Center for Biotechnology Information|NCBI]] bookshelf).
+*{{cite web |title=''Bordetella pertussis'' |work=ARUP Consult—The Physician's Guide to Laboratory Test Selection and Interpretation |url=http://www.arupconsult.com/Topics/Infectious_Disease/Bacteria/Bordetella_pertussis.html }}
+*{{cite web |title=Pertussis |publisher=United Kingdom Health Protection Agency |url=http://www.hpa.org.uk/infections/topics_az/whoopingcough/gen_info.htm }}
-* [http://www.arupconsult.com/Topics/Infectious_Disease/Bacteria/Bordetella_pertussis.html ''Bordetella pertussis''] in ARUP Consult — The Physician's Guide to Laboratory Test Selection and Interpretation
+*{{cite book |author=Centers for Disease Control and Prevention |chapter=Pertussis |chapterurl=http://www.cdc.gov/vaccines/pubs/pinkbook/pert.html |editor-last=Atkinson |editor-first=W. |editor2-last=Wolfe |editor2-first=S. |editor3-last=Hamborsky |editor3-first=J. |title=Epidemiology and Prevention of Vaccine-Preventable Diseases: The Pink Book |publisher=Public Health Foundation |year=2012 |edition=12th |url=http://www.cdc.gov/vaccines/pubs/pinkbook/index.html}}
+*{{cite web |title=''Bordetella pertussis'' |work=NCBI Taxonomy Browser |url=http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&id=520 |id=520}}
-* [http://www.hpa.org.uk/infections/topics_az/whoopingcough/gen_info.htm Pertussis] United Kingdom Health Protection Agency.
+{{Gram-negative bacterial diseases}}
+{{DEFAULTSORT:Bordetella Pertussis}}
 [[Category:Burkholderiales]]
+[[Category:Pertussis]]
-{{Proteobacteria-stub}}
+[[Category:Bacteria with sequenced genomes]]
-{{WikiDoc Help Menu}}

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