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Pertussis is a highly contagious respiratory disease caused by the bacteria Bordetella pertussis. Pertussis lives in the nose, mouth, and throat of infected individuals.
The bacteria are shed in nasopharyngeal secretions and can be spread through coughing, sneezing, or direct contact with fluids from the nose, mouth, or throat of an infected person. If untreated, infected individuals can spread the pertussis bacteria to others from 1 week before cough onset to 21 days after cough onset. Untreated infants (<1 year) remain infectious for up to 42 days from cough onset. When treated with antibiotics, the infectious period is reduced to 5 days after the initiation of treatment. Severe infections can result in complications such as pneumonia among all age groups. Seizures and encephalopathy generally occur only among infants. The average incubation period for pertussis is 7-10 days with a range of 4-21 days.
A cough illness lasting ≥ 2 weeks with at least 1 of the following signs or symptoms:
Paroxysms of coughing, OR
Inspiratory “whoop,” OR
Post-tussive vomiting, OR
Apnea (with or without cyanosis) (for infants <1 year of age only)
Targets the pertussis toxin promoter (ptxP): highly specific
Other locally available PCR tests for B. Pertussis
Singleplex assay: Typically, an in-house laboratory developed PCR method
Targets the insertion sequence IS481: highly sensitive
It is important to note research has found that PCR can detect pertussis in infants less than 6 months of age up to 3 weeks following pertussis treatment initiation. Pertussis positive PCR results may correspond to the presence of antibiotic-damaged bacteria. As a result, the clinical significance of pertussis detected by PCR after initiation of antibiotic treatment is unclear. For more information, see Real-Time PCR Measurement of Persistence of Bordetella pertussis DNA.
It is recommended pregnant women receive the tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis (Tdap) vaccine during each pregnancy. To maximize the maternal antibody response and passive antibody transfer to the infant, pregnant women should receive the vaccine between 27 through 36 weeks gestation. For more information, see Pregnancy and Whooping Cough.