Bordetella Pertussis

What is Bordetella Pertussis? Morphology and culture

B. pertussis is an immobile, gram-negative, short rod-shaped bacterium with a capsule form, strictly aerobic growth, very sensitive to cold and desiccation.

Bordetella Pertussis epidemiology

The only known host for B. pertussis is the man, diseases occur from infancy through to adulthood and are transmitted by droplet infection. Young people and adults to play as a reservoir of pathogens and vectors of increasing importance. The incubation period is 7-20 days, the period of infectivity begins at the end of the incubation period, increasing in the first two weeks, and disease is still up to three weeks in the convulsive stage remains in effect. Antibiotic therapy shortens the infectious capacity of about five days. Diseases occur mainly in autumn and winter, less in other seasons. Nosocomial infections due to a transmission by nursing staff in a children's hospital has been recently described.

Bordetella Pertussis pathogenesis

Are important virulence factors pertussis toxin, filamentous hemagglutinin and fimbriae on the adherence to the respiratory epithelium. The pertussis toxin (AB type) is an ADP-ribosyltransferase, which disturbs the signal transduction in the epithelial cell. The tracheal cytotoxin leads to stasis of the cilia of the respiratory epithelium.

The classic paroxysmal cough (staccato cough), followed by deep inspiration against a closed glottis in the convulsive stage. In the first infection in infancy, three stages can be observed:

• Catarrhal stage (lasting one to two weeks) with a slight cold, uncharacteristic cough, possibly a fever.
• Convulsive stage (lasting four to six weeks), heaped with paroxysmal cough especially at night, followed by the emergence of tough mucus choking and subsequent vomiting.
• Decrementi stage (lasting six to ten weeks) with gradual subsidence of the cough.

In adolescents and adults with the disease is long lasting cough without the typical seizures, in infants Apnoeen significant (deaths). Complications include pneumonia, otitis secondary, rare seizures or hypoxic encephalopathy.

Bordetella Pertussis diagnosis

The classic symptoms of whooping-cough is groundbreaking for a specific diagnosis. But also in children and adults with nonspecific cough bouts over a prolonged period (> two to three weeks), regardless of pertussis vaccination is recommended an investigation. In children under 12 months includes an absolute lymphocyte count of <9400/?L blood from a pertussis practical. Study materials for pathogen detection (culture, PCR) are deep Nasopharyngealabstriche, nasopharyngeal secretions, or aspiration of material. Ideal for removal is a Dacron swab, this should be done horizontally through one nostril to the posterior pharyngeal wall. By errors in the extraction and transportation (Kalte!) the estimates vary on the sensitivity of the culture between 30 and 60%, specificity 100%. Evidence of a PCR is currently not standardized and may not be available. The sensitivity of PCR is high, it also manages the detection of B. pertussis DNA in vaccinated individuals as well as in adolescents and in adults, where the culture is vastly inferior. However, false positive and false negative results are possible, new research protocols lead to a sensitivity of 100% and a specificity of 96.8%.

Detection of IgG and IgA antibodies at the earliest possible during the transition to the paroxysmal stage. Also important here is the examination of paired sera at intervals of two to four weeks.

Bordetella Pertussis treatment and prevention

The therapy is carried out primarily with macrolides [erythromycin (ERYCIN etc.), azithromycin (Zithromax and others), clarithromycin (Klacid etc.), roxithromycin (Rulide), alternatively cotrimoxazole (COTRIM etc.)]. Penicillins and cephalosporins are ineffective. The therapy should start as early as possible at the end of the incubation period, the catarrhal stage and use up to three weeks after the beginning of the paroxysmal stage (elimination period) will continue. However, antibiotic therapy affected only during the first two weeks after symptom onset the clinical course. In many cases, the duration and severity of coughing spells are not affected. Nevertheless, antibiotic therapy or prophylaxis for a break in the chain of infection to be significant (see below).

STIKO 2008 recommends a vaccination from the 2nd Month (a total of four doses) and booster doses at the age of five to six years and between 9 and 17 years. To reduce the transmission rate of young people and adults to infants or children can do a re-vaccination of adolescents.

The protection of a vaccine holds a maximum of 12 years. The administration of a dose of an acellular vaccine leads to nurses but to a long lasting immune response.

It should be noted that even unvaccinated individuals may be temporarily colonized with B. pertussis and thereby constitute a source of infection. Therefore, chemoprophylaxis with macrolides in close contact with persons in the family, the community or in community residential facilities for the preschool age is recommended, especially if there are in the area at risk.

A reporting requirement on the basis of regulations contained in the federal states of Brandenburg, Mecklenburg-Western Pomerania, Saxony, Saxony-Anhalt, Thuringia. Much the duty to inform the competent health authority for lines of community facilities in accordance with  34 para 6 is IfSG in disease cases.

Antibiotics are active against the Bordetella Pertussis