Status and problems of bacteriological diagnosis of diphtheria infection in the Russian Federation

Abstract

The purpose of the work was to assess the state of bacteriological diagnosis of diphtheria infection in Russia in order to establish possible reasons for the decrease in the release of C. diphtheriae. The Reference Center for Monitoring the Pathogens of Measles, Rubella, Mumps, Pertussis and Diphtheria in 2018 in 85 subjects of Russia conducted a questionnaire of laboratories of medical organizations and the Centers for Hygiene and Epidemiology of Rospotrebnadzor, carrying out bacteriological studies for diphtheria infection. It was found that the number of studies conducted over the five-year period decreased by 1.2 times. The tendency to decrease the number of bacteriological studies for diphtheria is observed in the territories of almost all federal districts. In 99% and 29% of cases, the institutions of the FBUZ Centers for Hygiene and Epidemiology and medical organizations (MO) and use in their work documents regulating bacteriological studies for diphtheria infection. In a number of territories, the list of documents used includes documents that are invalid or do not define such studies. Most organizations use dry tampons when examining for diphtheria, however, 13.1% and 53.4% of FBUZ Centers for Hygiene and Epidemiology and medical organizations (respectively) use commercial transport environments, which does not comply with regulatory documentation. Analysis of the quality of work of bacteriological laboratories showed shortcomings at the stage of preparation of media (use of donor blood, or absence of addition of blood and potassium tellurite), Elek tests (addition of horse serum or absence of serum to the medium), setting of incomplete biochemical series (absence of tests for urease and nitrate reductase), absence of standard control strains, incomplete volume of internal laboratory quality control. Given the continuing circulation of the pathogen in various countries of the world and in our country, as well as the possibility of imported cases of infection from endemic regions, the analysis was aimed at drawing the attention of specialists to the problem of improving the quality of laboratory diagnosis of diphtheria in Russia.

Effectiveness of Using Liquid Transport Media in Bacteriological Diagnostics of Diphtheria Infection

“…Габричевского Роспотребнадзора, для взятия биологического материала в ряде регионов России используются коммерческие транспортные агаризованные среды Стюарта и Эймса, предназначенные для изучения микрофлоры ротоглотки [9][10][11][12]. Нами ранее проведены исследования [12,13], которые показали, что при помещении биологического материала в агаризованные транспортные среды Эймса и Стюарта и их хранении в условиях комнатной температуры и холодильника в течение 6 ч рост единичных колоний токсигенного штамма C.diphtheriae получен только из большой концентрации микробной взвеси (5х10 4 м.к. ); выдерживание материала при комнатной температуре и в холодильнике в течение 20 ч вело к полной потере патологического материала; подращивание материала в термостате в течение 6 ч не даёт положительных результатов и не позволяет увеличить высеваемость возбудителя дифтерии.…”