Booster Vaccination: The Role of Reduced Antigen Content Vaccines as a Preschool Booster

Abstract

The need for boosters for tetanus, diphtheria, pertussis, and polio, starting from preschool age, is related to the waning immune protection conferred by vaccination, the elimination/reduction of natural boosters due to large-scale immunization programs, and the possibility of reintroduction of wild agents from endemic areas. Taking into account the relevance of safety/tolerability in the compliance with vaccination among the population, it have been assessed whether today enough scientific evidences are available to support the use of dTap-IPV booster in preschool age. The review of the literature was conducted using the PubMed search engine. A total of 41 works has been selected; besides, the documentation produced by the World Health Organization, the European Centre for Disease Control, and the Italian Ministry of Health has been consulted. Many recent papers confirm the opportunity to use a low antigenic dose vaccine starting from 4 to 6 years of age. There is also evidence that 10 years after immunization the rate of seroprotected subjects against diphtheria does not differ significantly between those vaccinated with paediatric dose (DTaP) or reduced dose (dTaP or dTap) product. The dTpa vaccine is highly immunogenic for diphtheria toxoids regardless of prior vaccination history (2 + 1 and 3 + 1 schedules).

Safety and reactogenicity of the combined diphtheria-tetanus-acellular pertussis-inactivated poliovirus-Haemophilus influenzaetype b (DTPa-IPV/Hib) vaccine in healthy Vietnamese toddlers: An open-label, phase III study

“… 9 Besides simplification of the increasingly crowded childhood vaccination schedule, combination vaccines have the potential to widen coverage, provide greater convenience, improve compliance, reduce health clinic visits and increase cost effectiveness. 9,10 Establishing vaccination awareness, reducing vaccine wastage rates and maintaining high immunization coverage in Vietnam is highly important. 11,12 To date, vaccination against diphtheria, tetanus, pertussis, IPV and Hib has been separately implemented in Vietnam.…”

Mycobacterium-Induced Th1, Helminths-Induced Th2 Cells and the Potential Vaccine Candidates for Allergic Asthma: Imitation of Natural Infection

“…In general, the conventional method to increase the efficacy of vaccines is the booster dosing ( 72 ), since repeated exposure to both antigen and polarizing cytokine is required for an effective immune response ( 73 ). In this regard, the BCG efficacy ranges between 0-80% and wanes over time ( 29 ), and it is classified as moderately effective vaccine ( 74 ).…”

Pertussis

“…However, the lack of long-term persistence of immunity protection implies that a major role is played by adolescents and adults, who are a significant source of infection for unimmunized or incompletely immunized infants. 68 However, it is important to bear in mind that the use of marketed vaccines worldwide has resulted in the achievement and maintenance of high rates of vaccine coverage which, regardless of the type of vaccine used and the number of its components, is the key factor for a successful vaccine intervention against pertussis.…”