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12 Cards in this Set
- Front
- Back
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Bacteria that cause Pertussis |
Most common: Bordetella pertussis Less than 5% of cases: B.bronchiseptica or B. parapertussis |
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How is the bacteria acquired? |
Through inhalation of respiratory droplets. |
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What happens in the body once B. pertussis is inhaled? |
The organisms then colonize the cilia lining the respiratory tract; it does not invade tissues or enter the blood but it does produce endotoxin, exotoxin, and hemagglutinins. The hemagglutinins help the bacteria attach to the cilia of the epithelial cells of the respiratory tract. The toxins produced destroy those epithelial cells which are then sloughed, leaving a surface of nonciliated cells. This surface allows mucus to accumulate within the respiratory tract. |
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How long is the incubation period? |
3-7 days |
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How many stages of progression does this disease have? |
Three: catarrhal, paroxysmal, and convalescent. |
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What happens in the catarrhal stage, and how long does it last? |
The catarrhalstage is characterized by fever, vomiting, sneezing, and a dry, persistent cough. Lasts 1-2 weeks |
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Second stage: paroxysmal. What happens and long does it last? |
Mucus and massesof bacteria fill the airway and immobilize the cilia. Sticky, ropelike strings of mucus in theairway then cause violent, paroxysmal coughing. During this stage, it is important tomaintain a patent airway. Airway blockage accounts for the high death rate in patientsless than one year of age. *Straining to draw in air gives the “whooping” sound fromwhich the disease received its name. The paroxysmal stage can last from one to sixweeks or longer. |
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What happens during the third and final stage, convalescent? |
Mild coughing maycontinue for several months before subsiding. Secondary infections are common duringthis stage. |
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How is pertussis diagnosed? |
Culture obtained from the posterior nasal passages. Because penicillin does not kill B. pertussis, it is usually added to the medium tosuppress other organisms. Once colonies appear, fluorescent antibody stain is used foridentification. |
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How is pertussis treated? |
Antitoxin and erythromycin. The antibiotic is given toshorten the paroxysmal stage by reducing the number of viable organisms being shed. Supportive measures such as suctioning, nutrition, electrolyte and fluid balance, andoxygen are important as well. |
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Can it be prevented? |
Yes, with a vaccine series thatbegins at two months of age. Pertussis antibodies do not cross the placenta, so it isimportant to get children vaccinated early as infants have no passive immunity to thedisease. |
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How many vaccines are there for Pertussis? |
Two: DTP and DTaP DTaP vaccine contains aP, which stands for “acellular Pertussis”. Thiswas developed in response to worries that the original pertussis vaccine (DTP, a whole-cellvaccine), was unsafe. |
