Bordetella pertussis, a highly contagious organism, has reemerged in the United States ever since the switch from the whole-cell pertussis vaccine (DTwP) to acellular pertussis vaccine (DTaP) was implemented partially in 1992 and completely in 1997. The DTwP was associated with a higher number of adverse effects which prompted the change to acellular pertussis vaccine despite it having lower reactogenicity and durability to immunity. The switch in the vaccination has been associated with the increase in the number of cases with periodic outbreaks in 2010, 2012 and 2014. In addition to increase in cases, since 2000 there is a change in the epidemiological profile of cases, from childhood cases to cases in adolescents and vaccinated children. The introduction of the booster dose “Tdap” produced a mild initial decline but has not prevented cyclical outbreaks which reached a peak of 48,277 in 2012 with 30–35% of those in the age group of 11–19 years. The reasons behind this change in epidemiological profile might be related to either waning immunity, which makes the adolescents more susceptible to the infectious agent, or genotypical changes in the bacteria leading to a selection of strains without vaccine antigens. The trend analysis done suggest that the earlier waning of immunity after acellular vaccination may have led to the emergence of B. pertussis with non-vaccine strains by selective vaccination pressure and this combined effect may have led to an increase in the number of cases and change in epidemiological pattern of the disease. Further research is needed to study the immunological phenomenon behind the reemergence of disease and the creation of a more tolerable whole-cell vaccine. In addition, a possible revision of immunization schedule should be considered, which includes first priming with the whole-cell vaccine (first 3 doses) and then booster with acellular vaccines.