Economic considerations for pertussis booster vaccination in adolescents.
BACKGROUND
Despite good acellular pertussis vaccine safety and protective efficacy, as well as high vaccination rates among young children, the incidence of pertussis in the United States has steadily increased since the 1980s. This is especially true for adolescents and adults who are susceptible because of waning immunity, which is not long lived. Other populations are at increased risk for morbidity of infection, although infants younger than 6 months of age who have not completed the primary immunization series have the greatest morbidity and mortality. Other groups who might benefit from booster immunizations include hospital workers, family contacts, and individuals with compromised health. Although older individuals generally have milder illnesses, they are often the source of infection for younger children. An adolescent/adult formulation of acellular pertussis vaccine requires a lower dose of pertussis antigens and can be combined with currently recommended diphtheria and tetanus toxoids (Tdap). These new vaccines for adolescents and adults are safe, immunogenic, and protective.


METHODS
Through an extensive review of the literature, the direct and indirect costs associated with pertussis and its complications are examined, cost-benefit analyses of pertussis booster vaccination are evaluated for different groups, and the economic considerations involved in implementing a pertussis booster vaccination program in adolescents are discussed.


RESULTS
Pertussis infections cause outbreaks in schools, families, and workplaces, resulting in prolonged morbidity and significant costs for medical care, lost time, and wages. Physician visits, chest radiographs, and antibiotics comprise the majority of direct costs, and costs associated with work loss often comprise the majority of indirect costs related to pertussis illness. Adolescents and adults also transmit their infections to nonimmune children. A cost-benefit analysis evaluated the health and economic benefits of seven strategies for administering a pertussis booster. The most economical strategy is to immunize all adolescents 10-19 years of age, which may prevent 0.4-1.8 million cases of pertussis and save US 0.3-1.6 billion dollars in a decade. A tetanus and diphtheria booster (Td) is currently recommended for children 11-12 years of age. The Tdap vaccine offers an enhancement for the Td booster by providing protection against pertussis, and it will not require an additional injection or office visit.


CONCLUSIONS
Immunizing adolescents with a pertussis booster in the form of Tdap is the most economical and easiest-to-implement strategy and should provide significant health and economic benefits.
Hay
Joel W
JW
Department of Pharmaceutical Economics and Policy, University of Southern California, Los Angeles, CA 90089. USA. jhay@usc.edu
Ward
Joel I
JI
D000293:Adolescent; D000328:Adult; D003362:Cost-Benefit Analysis; D006801:Humans; D007117:Immunization, Secondary / Q000191:economics*; D010567:Pertussis Vaccine / Q000191:economics*; D014917:Whooping Cough / Q000150:complications / Q000191:economics* / Q000517:prevention & control*
D010567:Pertussis Vaccine