Pertussis (Whooping Cough)

Increasing prevalence 1976 (lowest) vs. 2012, 1010 vs. 41,880 cases (14 deaths in infants aged <12 mo).

Substantial morbidity and mortality in USA children despite high childhood vaccination rates.

Incidence highest for infants <1 y of age (23% of all cases).

Adolescent group 10–19 y (33% of all cases).

Incidence of death highest for infants <6 mo of age (91% of all deaths).

Incidence greater among females than males (54%).

Incidence greater among whites than minorities (90%).

If unimmunized, 90% susceptibility following exposure to index case.

Only 2% of adult population is protected against pertussis.

Tdap vaccine coverage is 56% among adolescents and <6% among adults.

Most common complications occurring in those <6 mo of age: Hospitalization (69%), pneumonia (13%), seizures (2%), encephalopathy (<2%)

Common complications in adults: Cough-related incontinence (28%), syncope (6%), pneumonia (5%), rib fractures (4%), hospitalization (3%)

Infectivity and contagion

Secretions, pneumonia, altered mucociliary function, apnea, and decreased pulm reserves causing hypoxemia

Postop complications related to coughing

Pertussis is an acute respiratory infection caused by Bordetella pertussis.

Transmission occurs by respiratory droplets with a 7-d to 10-d incubation period.

Organism releases multiple toxins that damage the epithelial cells of the respiratory tract.

Characterized by three phases: Catarrhal (cold symptoms), paroxysmal (cough symptoms), convalescence (persistent or episodic cough).

Infectivity highest in catarrhal and early paroxysmal phases.

Adolescents and adults display milder symptoms that may be indistinguishable from less serious causes of URI/LRI.

Immunization in childhood has decreased but not eliminated incidence.

Vaccine estimated 80–85% effective after three exposures, usually given as combination Tdap vaccine.

Increased in incidence in adolescence (age 10–19), indicating a need for booster immunization.

In October 2012, the ACIP recommended administration of Tdap during each pregnancy irrespective of the pt’s prior history of immunization. Vaccinations given to pregnant women will stimulate the development of maternal antipertussis antibodies that will pass through the placenta, likely providing the newborn with protection against pertussis in early life protecting the mother from pertussis around the time of delivery, making her less likely to become infected and transmit pertussis to her infant. Optimal timing for Tdap administration is between 27–36 wk of gestation for maximal maternal antibody response and passive antibody transfer to the infant, although Tdap may be given at any time during pregnancy. However, the maternal antipertussis antibodies are short-lived.

B. pertussis, a fastidious gram-negative pleomorphic or rod bacillus.

A whooping cough syndrome can also be caused by Bordetella parapertussis, Chlamydia trachomatis, and many adenoviruses.