Effect of herpesvirus persistence on the formation of a specific immune response in children

Abstract

Introduction. The best way to reduce the incidence of vaccine-preventable infections is to create a population of highly immune individuals. This is achieved through the implementation of immunization programs. The main focus of most immunization programs are young children, for whom WHO offers routine immunization against diphtheria, tetanus, whooping cough, measles, epidparotitis, rubella, and poliomyelitis in developed countries. According to the WHO forecasts, the diseases caused by herpesvirus infections (HVI) in the near future are defined as "the global problem of mankind". A feature of HVI is that the immune system responds to the extracellular location of free virus particles or antigenic determinants, rather than to latent viruses in nerve ganglia, macrophages, lymphocytes, etc.: immune system reactions are not observed. HVI can provoke functional disorders in the cells of the immune system: macrophages, T-lymphocytes, violation of the blast-cell transformation of lymphocytes. Hence, apparently, there is a clinically sluggish state with seemingly normal (numerically) indices of cellular immunity, which requires immune therapy to activate the function of immunocompetent cells. According to, the problem of herpesvirus infections is most acute in pediatrics, which is associated with a poor knowledge of epidemiology, immunopathogenesis, clinical manifestations, therapy and, most importantly, prevention of exacerbations of HVI. The frequency of occurrence is now more than 40%. The most, perhaps, unpleasant is the increased number of relapsing forms in early school age (6-7 years). Recently there has been an increase in the number of people with secondary immunodeficiency, whose active immunization is ineffective. The purpose of the study. We studied the relationship between the formation of specific postvaccinal immunity and the persistence of various representatives of the Herpesviridae family in children under 7 years old who received the first vaccine of the PDA according to the vaccination schedule of Ukraine. Material and methods. 145 children aged 1 to 7 years were examined. Antibodies (Ab) of class G to measles, rubella and mumps viruses were determined by the ELISA method. The threshold concentration of Ab was calculated in IU/ml according to the instructions for the test systems that were used. Immunofluorescence and PCR were used to detect viral antigens (Ag) and DNA, respectively. Results and discussion. When analyzing the relationship between the persistence of herpesviruses and the imbalance of a specific immune response, it was noted that the absence of vaccinal immunity on the MMR correlates with the high viral load and the presence in the body of the child more than 3 representatives of herpes viruses. With hyperreactivity of a specific immune response, a direct relationship is observed with the detection of a combination of VEB + CMV + HHV6. It is precisely this combination of these heresviruses that has always been detected in children with superhigh titers of Ab in the MMR vaccine. Our studies showed that, on average, 17 ± 3.4% of children immunized against measles and rubella were vaccinated against measles and rubella, and 1.7 times more did not respond with the production of specific Ab in the mumps component of the vaccine. Especially it is necessary to pay attention to the fact that more than half of the children after the first vaccination have hypertensions Ab to rubella and, almost every third child, to measles and mumps. Especially the percentage of hyperreactivity increases in children 5-6 years, i.е. by the time the MMR is revaccinated, according to the vaccination schedule. At the time of vaccination, the child must be healthy. Ideally, and even more so when there are doubts, on the eve of the vaccination, a general blood test should be done. As our studies show, it is also necessary to conduct a study to identify the persistence of herpes simplex viruses in the child's blood cells. The depth of functional immunodeficiency is caused not only by the magnitude of the viral load, but also by the combination of herpetic infections. Excess immunization is unjustified in terms of medical ethics and economy. Some of them have a high initial level of antibodies and do not need to be vaccinated. Other individuals genetically produce high antibody titers during vaccination and do not require revaccination. It should be borne in mind that with intensive antibody formation, revaccination is unnecessary and undesirable. Conclusion. Therefore, it is desirable, but impossible for everyone today, to have a pre-vaccination screening - a serological examination of person’s subject to vaccination for the presence of immunity to the infection. Typically, the goal of pre-vaccination screening is to identify non-immune (seronegative for the causative agent of a specific infection) individuals. In rare cases, pre-vaccination screening is conducted because of the undesirability of exposing immune individuals to additional allergies associated with vaccination. This makes it possible to determine the need for immunization, to cancel further vaccination in persons with strained immunity or, conversely, to take measures to strengthen the immune response in the vaccinated person. First of all, the principles of individual vaccination should be extended to risk groups, which we believe should be attributed to children with persistent herpesvirus infection, which causes both the development of secondary immunodeficiency and allergic organism.