Vaccination and risk of allergy

Attempts in the past to link the growth of allergy in developed countries with "allergenic" vaccines have been convincingly refuted by studies showing the lack of influence of vaccines on levels of IgE and antibodies of this class. They were replaced by allegations that the cause of increasing allergization is a decrease in acute morbidity and, thereby, a decrease in stimulation of bacterial cells of the innate immunity system, which releases less Th-1-polarizing cytokines.

Recently, it has been suggested that the predominance of the Th-2 type immune response is associated with reduced stimulation of regulatory T cells. These assumptions correspond to the so-called "hygienic hypothesis" of the growth of allergic diseases, however, this hypothesis is based on data on the effect of contraction, mainly acute respiratory incidence in the first 6 months. Life of the child, whereas immunoprophylaxis prevents the majority of diseases at an older age. Moreover, studies of the possible protective role of administered infections in relation to allergies give conflicting results.

Nevertheless, a lot of population-based research on this issue has been conducted for each vaccine and all vaccines together. They gave contradictory results, largely reflecting the demographic and social characteristics of the studied population. Thus, the study of the effect of BCG on allergic morbidity did not reveal a significant effect in the Scandinavian countries, Estonia and Germany, while in Spain and Senegal a weak protective effect was observed.

Out of 10 reliable works on the influence of pertussis vaccine collected by these authors, 2 showed a weak positive relationship between allergy and DTP vaccination, in 2 negative cases, while 6 did not find it. Of the 7 studies of the effect of measles (or CPC) vaccination in 5, no relationship was found to the incidence of atopy, asthma, hay fever, while 2 studies showed a weak protective role of vaccination. Similar data were obtained with respect to OPV. On the basis of 2,500 children in the Netherlands, it has been shown that the vaccination of DTP + IPV + Hib vaccine does not increase the incidence of atopic eczema and recurrent obstructive bronchitis compared to those not fully vaccinated and not vaccinated.

The increase in the frequency of "reactive bronchial disease" described by individual authors after the use of pneumococcal conjugate vaccine was recognized by WHO as unconvincing.

Comparison of the curves of the incidence of asthma in children aged 5-14 years and the vaccine load in the US also does not confirm a connection between them: the incidence of asthma increased from 6 to 10% in 1980-1995, when the number of vaccinations on the calendar remained stable. In addition, observations were made for more than 1000 children for 14 years.

Observations in groups of children whose families follow the anthroposophical rules of life (natural nutrition, restriction of antibiotics, antipyretic drugs and vaccines) are interesting because this excludes the influence of a number of other possible effects. It was shown that the use of antibiotics and antipyretics at an early age does increase the incidence of asthma and other allergic diseases, but vaccination does not affect the incidence of allergic diseases.

By interpreting these data, it can be concluded that a decrease in the incidence of controlled infections due to vaccination is not accompanied by an increase in the incidence of allergic diseases. The positive effect of vaccination on the frequency of allergy, noted by the majority of authors, may be, although it is insignificant in terms of the strength of the effect in comparison with a set of other factors.