Following the coronavirus infection, a variety of symptoms may persist for a long time. Therefore, an important area of further research is to study the state and response of protective immune mechanisms in the post-COVID period. Our aim was to evaluate the dynamics of mucosal immunity by measuring sIgA in the saliva samples and nasal swabs (sIgA, lactoferrin), as well as efficiency of interferon-alpha-2b (IFNa2b) treatment in the patients after coronavirus infection. A study was conducted in the patients aged 18 to 60 years (n = 130) at the terms of 1 to 9 months after a coronavirus infection. A control group consisted of conditionally healthy individuals (n = 15). Diagnosis of post-COVID manifestations was carried out by collecting complaints, anamnestic data, physical examination and questionnaire. The state of mucosal immunity in saliva samples and nasopharyngeal mucosal scrapings was evaluated in dynamics as based on determination of sIgA and lactoferrin concentrations by means of enzyme immunoassay techniques prior to administration of local preventive therapy with recombinant IFNa2b, and 1 month after the treatment (VIFERON gel applied intranasally twice a day for 30 days). The following symptoms of post-COVID syndrome were documented In the study group: joint and muscular pain, shortness of breath, cough, fatigue and weakness, headache and dizziness, anxiety. In the group of patients who received preventive therapy during 1 to 3 months after coronavirus infection, a significantly increased level of saliva sIgA was noted, respectively, 1.840.28 to 5.781.96 mg/mL. As based on the data obtained with scrapings from nasopharyngeal mucosa, a significant increase in the level of sIgA was revealed in the group subjected to therapy up to 3 months after COVID-19 infection, i.e., from 28.613.0 to 39.833.85 mg/mL. In the group of patients devoid of preventive therapy, a stable maintenance of the reduced mucosal immunity parameters was found in all time intervals during the period of convalescence. In all observed patients, regardless of the group, a decreased lactoferrin level was found, being two-fold lower than the normal reference values. The incidence of respiratory viral infections in the group without preventive therapy was statistically significant, being registered in 9.2% of cases. Patients after COVID-19 infection exhibit a persistent decrease in mucosal immunity. Immunological efficacy was observed when using IFNa2b, thus making it possible to recommend it for rehabilitation in this group of patients over the period of convalescence.

Background. Atopic dermatitis (AD) treatment is based on clinical recommendations (CR, 2021). It is reasonable to use other effective treatment methods due to continuous and often relapsing course of dermatosis, and thus physiotherapy treatment is important.Objective. The aim of the study is to evaluate the efficacy of chromotherapy with a spectrum of 470 nm (blue spectrum) in children with AD complicated by secondary infection.Methods. The study included 40 children aged from 2 to 12 years. All patients received standard treatment regimen according to the current CR and were divided into 2 groups, equal in number (20 patients each): the control group (CG — only traditional therapy), and the experimental group (EG — traditional therapy + blue spectrum chromotherapy (470 nm)).Results. The SCORAD index (the sum of objective and subjective features) before treatment in the whole patient cohort was 32.5 ± 6.99 points, which corresponds to the moderate-severe form of the disease. The positive effect of therapy was registered in all patients (n = 40). Persistent process stabilization on the 7th day 7 of treatment in EG was observed in 8 patients, and in CG — in 2 (40% and 10%, respectively); p = 0.065. After the end of the treatment (10th day) persistent remission prevailed in EG and was registered in 90% (n = 18) of patients, and in CG — only in half of all patients, 55% (n = 11); p = 0.031. The evaluation of the AD severity due to the SCORAD index in patients with residual clinical manifestations clearly indicates that in EG its value corresponded to a mild disease course (p < 0.001), and in CG — the lower border of the moderate-severe and the upper border of the mild disease course (p < 0.05).Conclusion. The use of blue spectrum chromotherapy in treatment of children with AD is the effective and accessible method that can be used as an addition to traditional treatment in cases with secondary infectious complications. Its use has a potential to exclude polypragmasy in this dermatosis treatment.

Secretory immunoglobulin A, as a marker of the immune response in the mucous membrane, is an available indicator for detecting changes in the local immunity of mucous patients who have undergone COVID-19. Objective. To evaluate the dynamics of changes in the level of sIgA in saliva samples and the effectiveness of the use of interferon α-2b in individuals after a coronavirus infection. Patients and methods. Patients aged 18 to 60 years after COVID-19 infection (group 1 on therapy, n = 65; group 2 without therapy, n = 65) and conditionally healthy individuals (control group, n = 15) were monitored. The material is saliva samples, where the sIgA level was determined initially and after a month. The drug – interferon α-2b, in the form of a gel for topical use (Viferon®, dosage 36,000 IU/g) was administered intranasally 2 times a day, for 1 month. Results. In all groups of patients who underwent COVID-19, the level of saliva sIgA was lower compared to the conditional norm of healthy individuals (6,45 ± 1,81 mg/ml). A month after the administration of interferon α-2b the best effect was observed in patients in the time interval of 1–3 months from the infection, where sIgA was noted a statistically significant increase from 1,84 ± 0,28 to 5,78 ± 1,96 mg/ml. In the groups of patients with later terms, a moderate increase in sIgA was determined (3–6 months: 2,83 ± 0,71 to 3,33 ± 1,78 mg/ml; 6–9 months: 3,53 ± 0,45 to 4,76 ± 2,3 mg/ml) and the absence of infectious diseases during rehabilitation period. In the group without therapy, in all temporal aspects, a persistent decrease in sIgA indicators below normal values was revealed, and the frequency of incidence of respiratory viral infections was noted in 9,2% of cases. Conclusions. During the rehabilitation period, the greatest changes in sIgA in saliva were observed in patients in the first 3 months after the COVID infection. The administration of interferon α-2b to patients in the post-COVID period is accompanied by the normalization of sIgA and prevents the development of respiratory infections. In similar groups, after COVID-19 without therapy, the indicator tends to decrease, and this category of people is at a higher risk of developing other infectious pathologies. Key words: interferon α-2b, COVID-19, mucosal immunity, post-COVID period, secretory immunoglobulin A, saliva

The post-COVID-19 recovery period is characterized by persistence of some symptoms, with immunological alterations being of great importance. Development of preventive measures to normalize mucosal immunity after a coronavirus infection determines the relevance of the current study. The aim. To study dynamics of clinical symptoms and level of secretory immunoglobulin A in individuals after a novel coronavirus infection as well as evaluate effectiveness of using interferon alpha-2b. Materials and methods. A study was conducted with patients aged 18 to 60 years old (n=130), surveyed 1 to 9 months after post-infection, as well as in apparently healthy individuals lacking COVID-19 (n=15). Previous novel coronavirus infection and post-COVID manifestations were verified based on medical documentation, complaints, anamnesis data, physical examination and questionnaires. The concentration of salivatory and nasopharyngeal mucosal sIgA was measured dynamically prior to and after administration of local therapy with interferon alpha-2b (gel applied intranasally twice a day for 30 days). Results. The acute period of COVID-19 was characterized by fever, anosmia, fatigue and weakness, muscle and joint pain. Among the post-COVID manifestations at early period (1-3 months), pain in the joints and muscles (75,0%) as well as elevated body temperature (21,2%) were reliably detected, whereas in the long period (6-9 months) there were revealed dominance with the same frequency of shortness of breath, muscle and joint pain (75,8%, respectively). Based on examination data in healthy subjects, there was determined an arbitrary normal range of secretory IgA in saliva 6.451.81 mg/ml and nasal swabs 13.433.24 mg/ml. In the group of patients 1-3 months post-infection, therapy with interferon alfa-2b one month later resulted in significantly increased level of secretory IgA in saliva (from 1.840.28 to 5.781.96 mg/ml) and in nasal swabs (from 28.613.0 to 39.833.85 mg/ml) by more than 3- and 1.5-fold, respectively. In the group of patients without therapy was featured with stably sustained decline in sIgA level up to 9 months after COVID-19. In particular, the level of saliva sIgA ranged from 2.360.56 down to 2.160.66 mg/ml, and in nasal smears from 15.661.32 to 10.231.07 mg/ml that differed insignificantly compared to baseline level. The rate of respiratory diseases prevailed in this group (27.6% of cases), which fully lacked in the group of topically administered interferon alpha-2b. Conclusion. In the post-COVID period, multiple organ disorders persist and reduced sIgA level is registered. Intranasally applied interferon alfa-2b made possible to normalize sIgA level and prevent accumulation of respiratory infectious pathologies.

Immunological aspects of features of post-vaccine immune response to measles virus are presented and causal relationships are detected, that lead to the disappearance of protective antibodies against measles virus, as one of the arguments for improvement of vaccination tactics with the aim to increase immune population and enhancement of epidemiologic situation regarding measles in general. At contemporary stage during mass vaccinations against measles a portion of seronegatives among women of reproductive age and newborns (up to 20.1%) with an additional increase of this parameter by 8 - 13% during pathologic course of pregnancy is established. At the age of 12 months portion of seronegatives among children with health deviations reaches 80 - 90.0% against 53.8% - in healthy. Revaccination of children with deviation of health is shown not to result in production of antibodies against measles virus at protective titers in 30.4 - 33.3% of cases, that could facilitate formation of risk groups for measles virus infection during unfavorable epidemic situations. A problem of possible introduction of a third dose of the measles vaccine among the indicated population groups is discussed.