Pertussis is a contagious respiratory tract disease caused by the Gram-negative bacterium Bordetella pertussis. Despite widespread vaccination, in recent years the pertussis incidence has increased. The whole-cell pertussis vaccine has been very effective but reactogenic. Therefore the improved vaccines contain only a few isolated and inactivated antigens of B. pertussis. However, a waning of the acellular vaccine-induced immunity indicates that these vaccines lack some important protective B. pertussis antigens. The vaccine containing an inactivated pertussis toxin induces the production of toxin-neutralizing antibodies, but it does not lead to destruction of bacteria. Since many virulence factors are involved in the pathogenesis of pertussis, beside the toxin-neutralizing activity, the direct bactericidal activity is essential in anti-pertussis immunity. Lipooligosaccharide is the main surface component of B. pertussis. It is a target for bactericidal antibodies during natural infection. The endotoxic activity of LOS makes it unacceptable for acellular vaccines against B. pertussis. However, the non-toxic moiety of the B. pertussis LOS-derived oligosaccharide coupled to a carrier protein forms an immunogenic glycoconjugate which has a potential application as a new component of a pertussis vaccine. In this paper, we present a review of current research and reasons for the increased pertussis incidence. The epidemiologic situation of pertussis in the past decades showing the ineffectiveness of contemporary, acellular pertussis vaccines is also discussed. The immune processes elicited by natural infection with B. pertussis were compared to the vaccine-induced immunity. The important role of bactericidal antibodies against lipooligosaccharide was indicated in effective immune defense. In a number of research papers the immunogenicity and protective properties of glycoconjugates containing the oligosaccharide component of B. pertussis have been described, and its application as a new component of a pertussis vaccine have been implied.