Vol 65, No 5 (2020)

Introduction. One of the most urgent problem of modern medicine is the fight against the disease caused by the Human Immunodeficiency Virus (HIV) – HIV infection. The chemical compounds have improved the situation for infected people, but they are toxic, disrupt the metabolism and cannot eliminate the integrated virus from the body. The emergence of resistant HIV strains makes these treatments ineffective. Often, the death of HIV-infected people occurs as a result of the development of opportunistic infections caused by viruses of the Herpesviridae family. Therefore, the search for new therapeutic and preventive drugs that are less toxic and active against several viruses at the same time is relevant. Basidiomycetes, higher fungi, are a source of medicinal compounds that have antimicrobial properties, as well as antiviral ones. Humic compounds (HS) of various nature also have antiviral activity.

The aim of the study was to obtain nontoxic compounds from the basidiomycete Inonotus obliquus and humic compounds from brown coals and to test their activity against viruses that are pathogenic to humans: HIV and Herpes Simplex Virus (HSV).

Material and methods. The antiviral activity of melanin extracts obtained from the culture of the chaga fungus Inonotus obliquus and HS from the brown coal of the Kansko-Achinsk Deposit was studied using a model of MT-4 lymphoblastoid cells infected with HIV type 1 (HIV–1) strains and a monolayer culture of Vero cells infected with HSV type 1 (HSV-1) using virological and statistical research methods.

Results and discussion. It was found that all the studied compounds did not have a cytotoxic effect on cells at a concentration of 100 mcg/ml. It was shown that extracts of basidiomycetes and HS have antiviral activity against HIV-1 and HSV-1. EC 50 (50%-effective concentration) for HIV-1 was 3.7–5.0 mcg/ml, selectivity index 28–35. Antiherpetic activity was detected at a dose of 50–100 mcg/ml. The antiviral effectiveness of melanin compounds was established both in the «preventive» (2 hours before cell infection) and in the «therapeutic» regimen of drug administration, both for HIV-1 and HSV-1. The presence of antiviral activity of melanin and HS in relation to the RNA-containing HIV-1 virus and DNA-containing HSV-1 virus in our study coincides with the results of a number of authors in relation to influenza viruses, herpes virus, HIV, hepatitis B virus, Coxsackievirus, smallpox vaccine virus, which suggests that the type of nucleic acid in the virus does not play a fundamental role in the antiviral action of these drugs. It is also clear that HS is effective against both enveloped and non-enveloped viruses.

Conclusion. In general, it can be concluded that melanin and humic compounds are characterized by low toxicity in the presence of both virucidal and antiviral activity. This allows us to consider the studied compounds as the basis for creating safe medicines that are effective against pathogens of various viral infections.

Introduction. Measles remains an urgent problem in Russian healthcare. Despite the ongoing vaccination, there is an increase in the incidence of measles. Prevention of measles is particularly important in high-risk groups, as well as among healthcare professionals to prevent hospital-acquired outbreaks of infection. The duration of post-vaccination immunity during the elimination of measles has not been sufficiently studied, so often people who  have had measles in childhood or have 1–2 vaccinations against the disease lose their protective antibodies with age in the absence of natural boosterization.

Goals and objectives. To study the intensity of specific immunity to measles in employees of the maternity unit.

Material and methods. The study involved 271 employees of the maternity unit aged 21 to 93 years (262 serum samples). The level of IgG antibodies (Ab) to the measles virus in the blood serum was studied by ELISA using a standard set of reagents for the quantitative determination of IgG by «VECTOR-BEST». The result was  considered negative if the concentration of IgG to the measles virus in tested sample was ≤ 0.18 IU/ml and  positive – if > 0.18 IU/ml. 

Results. The number of seronegatives ranged from 0% to 30.8% in female employees with its maximum at age of 31–35 years. The lowest proportion of seronegative and the highest proportion of seropositive women were observed among the elderly, > 60 years.

Discussion. There is a marked tendency for an increase of the proportion of persons with average Ab levels with age and a decrease of the proportion of persons with low Ab levels. The percentage of seronegative women among employees exceeded the recommended level, which makes it possible for an nosocomial outbreak when an infection is introduced.

Conclusion. The authors recommend that serological testing for the intensity of the immune response against measles should be included in the standard of the pre-vaccination screening for adults.