US Pharm. 2015;40(4):26.
Pertussis (whooping cough) is a contagious respiratory disease caused by Bordetella pertussis. Between 1940 and 1945, about 175,000 people developed pertussis each year, fatally in 2% of cases. A 77% decline in the annual number of infections was seen following initiation of routine childhood pertussis DTP (diphtheria, tetanus toxoids, and whole-cell pertussis vaccine), dropping to 1,010 cases in 1976. Pertussis is reported to the CDC through the National Notifiable Diseases Surveillance System. The number of pertussis cases has increased since the 1980s, particularly in adolescents and adults; in 2013, more than 28,000 new cases were reported.
Prevalence and Complications: From 2000 to 2004, an average of 2,488 cases of pertussis were reported annually in infants aged <12 months. Of these cases, hospitalization was necessary in 63%, with a median duration of hospitalization of 5 days. In 2009, 4,265 of the nearly 17,000 patients with new cases of pertussis were aged 10 to 19 years. Of infants aged <1 year who were hospitalized for pertussis, 67% had apnea, 23% developed pneumonia, 1.6% had convulsions, 1.6% died, and 0.4% had encephalopathy. Of adolescents and adults with pertussis, in addition to the complications noted in the accompanying chart, 5% were hospitalized and 2% developed pneumonia.
Vaccination Trends: In 2005, two Tdap (tetanus, diphtheria, and acellular pertussis vaccine) products were approved for use in adolescents (one of these also approved for adults). According to the 2010 National Immunization Survey, 69% of adolescents aged 13 to 17 years received Tdap, despite the recommended age of 11 to 12 years for vaccination. In 2012, even though 83% of children aged 19 to 35 months and 85% of adolescents aged 13 to 17 years, respectively, received the recommended doses of DTP/DT (diphtheria and tetanus toxoids)/DTaP (diphtheria and tetanus toxoids and acellular pertussis vaccine) and Tdap vaccines, 18,719 new cases of pertussis were reported.
Strategies: Increasing the rates of immunization among adolescents is an important strategy for reducing disease in adolescents, as well as in infants, who are too young to be fully immunized against pertussis. Tdap is recommended for children aged 7 to 10 years who are not fully immunized. Because immunity from childhood DTaP vaccines wanes by adolescence (among susceptible individuals, 5-10 years after completion of childhood pertussis vaccination), a booster dose is recommended. The CDC recommends that adolescents aged 11 to 18 years and individuals aged ≥19 years (who did not receive Tdap in adolescence) receive a single dose of Tdap—especially those in close contact with infants—as protection against pertussis, even if they completed the recommended childhood DTP/DTaP vaccination series.
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