The frequency of AB0 and Rhesus blood groups was studied in 12120 patients with COVID-19, 5180 convalescent plasma donors and 118801 healthy donors from Moscow, Smolensk, Yakutsk, Minsk and Gomel. In infected individuals, the frequency of blood group A was significantly higher than in uninfected individuals (41,54 % and 34,39 % respectively, p<0,05), and the frequency of blood group 0, on the contrary, was significantly lower (27,69 % and 36,71 %, p<0,05). The frequency of blood group A was particularly high among patients who died from ARVI COVID-19 - 45,51 % vs. 34,39 %, p=0,008. In some groups of patients, there was a decrease in the frequency of Rh-negative individuals (2,23 % vs. 8,30 %, p<0,001).

Objective. In this study, we examined the prevalence of macrolide-resistant M. genitalium in two Russian cities, Smolensk and Tula, between 2013 and 2017. Materials and Methods. DNA’s samples were isolated from urethral and cervicovaginal swabs using primary screening and tested for macrolide resistance-associated mutations by real-time PCR. This technology makes it possible to identify any nucleotide substitutions in the 23S rRNA M. genitalium gene at positions 2058, 2059, 2611 M. genitalium by melting curve analysis after the amplification. Results. According to the study in two cities (Smolensk and Tula) macrolide resistance-associated mutations were found in 3, 65% of isolates (21⁄574). The A2058G transition 23S rRNA MGE was the most common mutation that is associated with macrolide resistance: 5⁄12 (41.6%) – Smolensk, 8⁄9 (88.8%) – Tula. Rare substitutions have been reported at position A2058T 23S rRNA MGE and at position C2611T23S rRNA MGE. All received data is published at the AntiMicrobial Resistance Map (AMRmap) (http://AMRmap.com). Conclusions. According to our study, the frequency of macrolide-resistance mutations in M. genitalium was not more than 4% in two cities of Central Russia during 2013–2017. Despite the relatively low rates of resistance of M. genitalium to macrolides in Smolensk and Tula, our data emphasize the need for epidemiological surveillance of resistance in this pathogen.

Mycoplasma genitalium is one of the obligate pathogens that cause sexually transmitted diseases. To detect this pathogen in routine practice, only molecular genetic methods are used that are also used to identify the resistance of MGE to antibiotics. The first-line drugs for the treatment of diseases caused by MGE, are tetracycline and macrolides. In recent years, many countries have increasingly recorded cases of unsuccessful therapy macrolides. Mutations that confer antibiotic resistance to macrolides for Mycoplasm genitalium are concentrated in nucleotide positions 2058 and 2059 in region V of the 23S rRNA gene. Unknown status of macrolide resistance M. genitalium can lead to the development of a persistent infection. We describe the first reported cases of clinical josamycin treatment failure from patient with ure - thritis. The reason for antibiotic resistance was a mutation in the 23S rRNA of MGE as a nucleotide substitution in position A2058G.

Objective. To determine spectrum and prevalence of genetic determinants of resistance to macrolides in Mycoplasma genitalium in a Russian patient population. Materials and Methods. A total of 873 M. genitalium-positive samples from five geographical regions of Russia were investigated over the period of 2009–2019 using the previously developed protocol of real-time polymerase chain reaction (allows detecting any nucleotide substitutions in the 23S rRNA gene of M. genitalium at positions 2058, 2059, and 2611). The results were confirmed using Sanger sequencing. Results. The most frequent mutations associated with resistance to macrolides in M. genitalium were the following: A2058G (60.5%) and A2059G (30.2%). The relatively rare mutations were A2058T (7%) and C2611T (2.3%). In the studied period, there was no trend to increase in frequency of mutations associated with resistance to macrolides. The study results are presented as an open project on the AMRcloud platform (https://amrcloud.net/ru/project/demares/). Conclusions. Our data emphasize a need to introduce regular screening of M. genitalium-positive samples for the presence of macrolide resistance-associated mutations into clinical practice.

Introduction. Polysaccharides, glycoproteins and glycolipids, which determine the group-specifi c properties of human blood, are both structural elements of the whole organism and determine its predisposition to certain somatic and infectious diseases. Thus, the blood group of an individual can be used among other markers and/or prognostic factors of the occurrence and course of certain groups of diseases.Aim — analysis of literature sources characterizing the relationship of blood groups with COVID-19 ARVI, as well as the mechanisms underlying this relationship.Main findings. The Oaß(I) phenotype ensures an individual’s resistance to infection with the SARS-CoV-2 virus and allows for a relatively mild course of the disease. The Aß (II) phenotype is a risk factor for the development of COVID-19 ARVI, in its severe course, the occurrence of complications and increased mortality. An additional component of protection in the form of a negative Rh-affi liation of the infected person is not excluded. The protective properties of the Oaß(I) phenotype are associated with the absence of polysaccharide A in an individual and the presence of anti-A antibodies. The increased risk of COVID-19 ARVI among Aß (II) individuals is due to the large polymorphism of polysaccharide A in the environment and the lack of natural immunity to other forms of polysaccharide A in this group.