The paper presents the literature data analysis and statistical reports on the population morbidity of larval helminthiases in Russian Federation over the past 20 years. Epidemiological aspects of larval helminthiases in areas with different climatic, geographic and socio-economic conditions were determined.

The article presents the results of the investigations of Rostov Research Institute of Microbiology and Parasitology of Rospotrebnadzor which are directed towards the optimization of epidemiological surveillance of the larval helminthes infestations which are actual for the South of Russia: echinococcosis, trichinosis, dirofilariosis and toxocariasis. The implementation of the improved system of epidemiological surveillance of trichinosis has led to the absence of this disease cases among the population of the South and North-Caucasian federal districts in 2017. The optimization of preventive measures allowed to reduce the echinococcosis morbidity of the population in 2017 in the most unfavourable for echinococcosis region - Republic of Karachay-Cherkessia - twice compared to 2009. The results of sanitary-parasitological investigations - the most important part of epidemiological surveillance - indicate the potential risk of the population's infestation with parasitic pathogens through the objects of the environment in the South of Russia. The work of the researchers of the Institute together with the organizations of Rospotrebnadzor and other departments on the improvement of epidemiological surveillance resulted in the development of 12 standard and methodical and informative and methodical documents for the period of 2013-2018.

The main trend of HIV epidemic development in Southern Russia is identical to Russia’s nationwide but less intense. High incidence rates are registered in such regions that have a saturated prevalence of HIV infection at the population level. During 1998–2018 an annual increase in HIV incidence has permanent vacillation ranging between +5 and +15%. This vacillation turned to be influenced by insufficient routine HIV testing coverage, which has always been lower than Russia’s nationwide rate and hardly ever reached 20% until 2017. The HIV incidence steadily biases into the age of 30–44 and elders. Sexual transmission of HIV predominates in the South since 2004. There are sustained agencies by which new HIV infections occur in Southern Russia and upward trajectory of HIV epidemic.

Objective: to study the circulation and prevalence of phage-resistant strains among opportunistic enterobacteria, isolated from children with disorders of intestinal microflora, in relation to domestic preparations of bacteriophages.Materials and methods. A bacteriological study of the fecal microflora of the colon in 970 young children for dysbiosis was carried out. The sensitivity of 720 antibiotic-resistant strains of opportunistic enterobacteriaceae (S. aureus, K. pneumoniae, P. mirabilis and P. vulgaris, P. aeruginosa, E. coli, coagulase-negative staphylococci) isolated from children to domestic mono- and polyvalent drugs was studied (coliprotein, staphylococcal, Pseudomonas aeruginosa, purified Klebsiella pneumonia bacteriophage, “Sextafag”, Intesta bacteriophage). Determination of sensitivity to bacteriophages was carried out by the “sterile spot” method. Antibiotic sensitivity was determined by the disk diffusion method. Statistical processing of the results was carried out using the Microsoft Office Excel 2007 software package.Results. A large percentage of phage-resistant strains with low sensitivity to bacteriophages was revealed among opportunistic bacteria, amounting to 54,2%, with the highest circulation among coagulase-negative staphylococci, Proteus, Klebsiella (more than 50%). A significant spread of intestinal dysbiosis was established in young children (87,5%), characterized by a low content of bifidobacteria and a high level of allocation of opportunistic enterobacteria, including in associations.Conclusion. As a result of the studies, a significant prevalence of phage-resistant strains in children with dysbiosis was revealed, which indicates the need for preliminary determination of their sensitivity to bacteriophages in order to resolve the issue of their possible inclusion in the intestinal microflora correction system.