Implementation of cholera monitoring tasks in 2020 under COVID-19 restrictive measures

Abstract

In connection with the development of the epidemic process of coronavirus infection on the territory of Russia in 2020, monitoring studies of environmental objects for the presence of Vibrio cholerae in surface water bodies and drains were carried out against the background of restrictive measures, the volumes and time of introduction of which were not the same in different regions of Russia. The purpose of the study was to assess the implementation of cholera monitoring tasks in 2020, in the context of the introduction of restrictive measures associated with the new coronavirus infection. Materials and methods. We used 25 nontoxigenic strains of Vibrio cholerae isolated from water bodies of the environment in 2020 on the territory of Russia. Identification was carried out in accordance with MUK 4.2.2218–07 «Laboratory diagnostics of cholera», including using the MALDI-TOF method to establish the genus and species of the isolated cultures. PCR genotyping was performed using an extended spectrum of genes. Cluster analysis was performed using the UPGMA method. Results and discussion. Against the background of the introduction of restrictive measures, the intensity of monitoring studies did not decrease. On the territory of four federal districts in seven constituent entities of Russia, 25 strains of cholera vibrios O1 and R-variant were isolated from environmental objects, which is comparable to the indicators of previous years. A comprehensive study of biological properties was carried out that revealed the distribution of isolates into groups according to the criterion of combined distinctive features (phenotypic and genotypic), as a result of which the isolated V. cholerae O1 strains were divided into seven groups. It was shown that the largest number of V. cholerae O1 strains isolated from water bodies fell on the territory of the Southern Federal District. Relationships have been established between a certain group of Vibrio cholera strains and the place of their isolation. Thus, the restrictive measures introduced in Russia in 2020 in connection with the COVID-19 pandemic did not affect the intensity and effectiveness of monitoring studies, the tasks of monitoring cholera in the country were implemented.