A review of the epidemiology of clinical rubella in the Perm region of the Russian Federation from 1979-97 showed that the incidence was about 220 cases per 100,000 population. Congenital rubella syndrome (CRS) accounted for 15% of birth defects and for about 3.5 cases of CRS per 1000 live births per year. Surveys of the seroepidemiology of rubella infection revealed that the susceptibility rate among pregnant women (i.e. rubella virus antibody haemagglutination-inhibition (HAI) assay titres < 10) was 16.5%. As serum rubella antibody HAI titres > or = 10 both prevented infection in pregnant women and protected their foetuses, serological testing has been introduced into the routine antenatal services. Pre-existing rubella antibodies were found not to interfere with the immune response to vaccination, so selective immunization was provided to girls approaching puberty and to women of childbearing age. A programme of epidemiological surveillance is being developed to define tactics for the widescale introduction of rubella vaccination.

Abstract. Ascorbic acid (vitamin C, AA) is an essential nutrient of the human diet due to its participation on numerous regulatory and enzymatic processes. AA takes part in such vital physiological processes as hormone production, collagen synthesis, stimulation of the immune system, etc. In the present review the activities of AA are considered that provide its protective effect at influenza infection. This effect can be result of direct virus-inhibiting activity of AA as well as of anti-inflammatory and antioxidant properties. Oxidative stress during influenza infection leads to nonspecific damage of the pulmonary tissue and subsequent inflammation of the lungs. The antioxidant activity of AA results in alleviation of infection due to suppression of tissue damage as well as in inhibition of reactive oxygen species-mediated signal transduction and regulatory reactions. After oxidation by ROS, AA is converted to dehydroascorbic acid (DAA) and inhibits the key enzymes of NF-κB pathway, such as kinases IKKα and IKKβ. AA itself blocks the activity of another component of the NF-kB pathway, kinase IKKβ(SS/EE), whose activity is directed to the phosphorylation of the factor IκBα. As a result, activation of NF-κB and its transport to the nucleus does not occur. Thus, AA performs a dual function: first, it neutralizes free radicals, preventing them from activating NF-κB, and secondly, the product of its oxidation, DAA, further blocks the activation of this pathway. In addition, in some cases AA results in the decrease in the infectious activity of influenza virus that is not due to the antioxidant activity of AA, but to direct virus-inhibiting activity. Taken together, the presented data suggests that the use of drugs with antiviral and antioxidant activity, as a combination of individual drugs or, as in the case of AA, as a single drug with complex activity, for treatment of influenza has advantages over the etiotropic drug monotherapy scheme. Резюме. Аскорбиновая кислота (витамин C, АК) является важным пищевым компонентом для человека благо-даря ее роли в различных регуляторных и ферментативных процессах. АК принимает участие в таких жизненно важных физиологических процессах, как продукция гормонов, синтез коллагена, стимуляция иммунной си-стемы и пр. В настоящем обзоре рассмотрена активность АК, обеспечивающая ее протективный эффект при гриппозной инфекции. Этот эффект может быть обусловлен прямой вирусингибирующей активностью АК, а также ее противовоспалительными и антиоксидантными свойствами. Окислительный стресс при гриппе ведет к неспецифическому повреждению ткани легких и развитию воспаления. Антиоксидантная активность АК приводит к облегчению течения инфекции вследствие снижения уровня повреждения ткани и ингибиро-

A goal for measles elimination globally by 2010–2020 was recognized as one of the priorities in the WHO program “Health for All in the 21st Century” (1998). However measles outbreaks occurred in 2010–2016 in countries with high level of measles vaccine coverage including USA and some European countries.Large measles outbreaks were also registered on the African continent and particular in the Republic of Guinea as a result of the decline of measles vaccine coverage due to the Ebola virus epidemic in the Republic of Guinea in 2014–2015. WHO recommends carrying out the routine measles vaccination as well as the supplemental immunization activities after the stop of the Ebola virus transmission. Effectiveness of the activities is definitely connected with the detection of the epidemically significant for the supplemental immunization age groups. The aim of the study was to evaluate the measles immunity level in different age groups of population in the Republic of Guinea. Materials and methods. Twenty five blood serum samples of healthy adult Guineans aged 28–66 and 121 blood serum samples of adolescences and adults admitted to hospital in the town of Kindia (Republic of Guinea) for indoor treatment were tested by ELISA. The specific measles virus antibodies were detected using the following commercial ELISA test-systems produced by Euroimmun Medizinische Labordiagnostika AG Company (Germany): IgM-antibodies — by “Anti-Measles Virus ELISA (IgM)”, IgG-antibodi es — by “Anti-Measles Virus ELISA (IgG)”, IgG-avidity measles virus antibodies — by “Avidity: Anti-Measles Virus ELISA (IgG)”. A part of sera was studied by “Vector-Best IgM-measles” and “Vector-Best IgG-measles” ELISA test-systems (Russia). Results and discussion. The comparative quantitative study of the measles immunity level (i.e. IgG-antibodies titers) of the healthy adult Guineans in 2015 and 2016 revealed the lack of IgGantibodies in serum of only one person aged 30. In 68.7% of cases studied the IgG-antibodies titers didn’t change significantly during the year. In the most part (68.0%) of the 25 tested sera the high levels of the IgG-antibodies titers were detected (≥ 1000 IU/L). In addition the IgG-antibodies of high avidity were revealed in the most part (87.5%) of blood serum samples thus evidencing the history of measles virus infection in the past among the examined adults aged 28+. The ELISA studies of 121 blood serum samples from patients with different clinical diagnosis being on indoor treatment in the hospital of the town of Kindia (Republic of Guinea) revealed 21 anti-measles IgG negative patients. Among patients with the known age (n = 113) IgG-antibodies to measles virus were determined in 78.8% of the samples tested. At the same time in each age group the seronegative patients as well as the patients with low titers of the specific IgG-antibodies to measles virus were revealed. Among patients of 18–40 years of age the part of seronegative patients was equal to 28.5±5.1%. This cohort may be susceptible to measles virus infection and facilitate the support as well as the development of active epidemic process in case of measles outbreaks in the Republic of Guinea.

SummaryParvovirus B19 (PVB19) is a well known DNA virus which seems to be associated, e.g., with erythropoiesis disturbances. Being a latent virus, the PVB19 may become active in immunocompromised patients. However, clinical significance of PVB19 after hematopoietic stem cell transplantation (HSCT) is yet not clear. Therefore, the aim of our study was compare the PVB19 DNA levels prior to allogeneic HSCT, and at 1-2 months post-transplant, as well as search for correlations with specific antibody levels and possible effects upon hematopoietic recovery within 60 days after HSCT. Our study included 54 pediatric and adolescent patients of 0.6 to 19 years old with blood malignancies or inherited disorders who underwent allogeneic HSCT. Fifty-one patient of this group were observed for at least 60 days after HSCT. 33% of the patients were in first remission after previous treatment. Non-myeloablative conditioning treatment was used in 94% of cases. Antilymphocyte immune globulin and/or cyclophosphamide were applied as immunosuppressive therapy. Determination of the PVB19 DNA as well as herpesviruses (CMV, EBV, HSV) and polyomaviruses (BK, JC) was performed before conditioning therapy which preceded allo-HSCT, as well as on day +30 (D+30) and day+60 (D+60) post-transplant. Quantitative determination of the PV B19 DNA was performed by gene-specific real-time PCR using commercial kits. IgG and IgM antibodies to PVB19 were determined quantitatively by means of ELISA method.Results of the study were as follows: PVB19 DNA at low levels was found in blood plasma samples of 31.5% HSCT patients. However, 68% of the patients exhibited detectable levels of IgG-anti-PVB19 antibodies (>10 IU/ ml), thus reflecting high prevalence of adaptive immune response. Generally, prevalence and mean levels of PV B19 DNA as well as concentrations of anti-PV B19 antibodies did not show any significant changes at 30 or 60 days after HSCT.Meanwhile, a significant positive correlation was revealed between the overall PVB19 viral load and serum levels of IgG antiviral antibodies (r=0.351; p<0.0001). Moreover, positivity for PVB19 DNA by the day +30 after allo-HSCT was in all cases (14/14), associated with febrile neutropenia in the patients, thus suggesting their potential role in posttransplant infections.Specifically, important correlations were observed between initial parvovirus DNA detection, and delayed reconstitution of erythrocytes and platelets in peripheral blood (respectively, r=-0,281; p=0.02; r=-0,303, p=0.01). Moreover, a marked correlation was shown by the day +60 between decreased neutrophils and platelet counts, and increased anti-PVD19 antibody levels. This finding may suggest an association between parvovirus activation and slower hematopoiesis recovery after allogeneic HSCT.

No abstract