The study of Bordetella pertussis, unfortunately, is still remarkably relevant. As of 2004, whooping cough is a major cause of childhood disease. In nations where vaccination is not used, fifty-one million cases of whooping cases are estimated each year (Todar 2001). Although research has elicited much of the role of the immune response in response to this pathogen, more work remains. Chief among these concerns is a complete, clear picture of cell-mediated, humoral, and innate responses to B. pertussis. This site and many researchers pursue the goal of integrating experimental evidence into a description that allows development of specific treatment. As of now, much of what we know about B. pertussis is based upon the infection of mouse models with the pathogen. While the development of this model has led to many strides in understanding pertussis, the natural habitat for B. pertussis is human respiratory epithelium. Careful, informed studies in humans would contribute to our knowledge (Mills 2001). Other options also appear; pigs have been intrapulmonarily infected with B. pertussis. Given the anatomical similarities, this model may reflect accurately upon aspects of human infection (Elahi et al. 2005).
The study of immune responses to B. pertussis goes hand-in-hand with the development of effective means to treat infection. Future study concerns will certainly extend to responses to whooping cough vaccines as well as the development of new and improved vaccines. Of central importance at the present is possibility of antigenic divergence among vaccine and circulating epitopes of B. pertussis components (Hijnen et al 2004). Furthermore, the side effects of vaccination must be considered. Whole cell vaccination problems, including alleged adverse neurological effects, have by and large been avoided by acellular vaccines (Loscher et al. 1998, Mills 2001). Local reactions of swelling and redness are still reported with relatively high frequency with the acellular vaccine (Mills 2001).
With either whole cell or acellular vaccination, as well as with natural infection, the secondary response to B. pertussis appears to be amnesiac. Typical vaccination with a single booster treatment lead to protection for six to twelve years, but immunity is lost afterwards. Since young children are the most vulnerable to severe pertussis infections, vaccination plans have focused upon this demographic. This scenario has created a shift in the epidemiology of the disease (de Carvalho and Pereira 2006). Adolescents and adults are increasingly experience pertussis pathology. Whooping cough vaccines are typically given in five stages, as part of a DTP (diphtheria, tetanus, pertussis) combination regime. These shots are given at two, four, six, twelve to eighteen months, as well as at four to six years old (Todar 2004). The nature of immunity to pertussis, however, questions whether further boosters are need for adolescents and/or adults (de Carvalho and Pereira 2006). Furthermore, more immunological research into the source of this immunological “forgetting” of B. pertussis would be relevant for the treatment of infection.
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