Nosocomial Outbreak of Multidrug-Resistant Tuberculosis Caused by a Strain of Mycobacterium tuberculosis W-Beijing Family in St. Petersburg, Russia

Abstract

A molecular epidemiologic study of 35 Mycobacterium tuberculosis isolates from 19 patients was conducted to define a nosocomial outbreak of multidrug-resistant tuberculosis in St. Petersburg, Russia. IS 6110-restriction fragment length polymorphism (RFLP) fingerprinting, together with investigations to detect mutations conferring drug resistance, revealed relationships between the isolates and links between the cases. Three patients and a nurse exposed to active tuberculosis were proved to be involved in the outbreak; the source case was identified. The outbreak strain possessed a 17-band RFLP pattern and a spoligoprofile (signals 35-43) characteristic of the W-Beijing family as well as distinctive mutations in katG315, rpoB531, embB306 and rpsL43. This specific RFLP pattern has previously been identified among Mycobacterium tuberculosis W-Beijing strains isolated across the former Soviet Union and in the St. Petersburg area of Russia. The spread of multidrug-resistant strains of W-Beijing genotype in the general population and in hospital settings presents a serious threat for public health in Russia. Specific pathogenic properties of W-Beijing genotype strains, such as enhanced transmissibility and the ability to cause reinfection and to readily acquire drug resistance to major antituberculosis drugs, along with special features of host response, have yet to be investigated.

Barriers to successful tuberculosis treatment in Tomsk, Russian Federation: non-adherence, default and the acquisition of multidrug resistance

“…Reinfection of patients on therapy for drugsensitive disease has been described in several different high-incidence settings and has been associated with nosocomial transmission. [27][28][29][30][31] Usually, MDR-TB patients in the Russian Federation are not placed on respiratory precautions in the hospitals or clinics where they receive care, so there is opportunity for further spread of drug-resistant strains among patients receiving therapy for drug-sensitive disease. The finding that substance abuse was a risk factor for late occurrence of MDR also raises the possibility that these patients are at higher risk of exposure to drug-resistant disease or are more susceptible to reinfection than other patients.…”

Southern East Asian origin and coexpansion of Mycobacterium tuberculosis Beijing family with Han Chinese

“…Lineage 2 contains strains that mostly belong to the so-called Beijing family (8,9). This strain family has attracted great attentions due to its global emergence in recent decades (6,7,(10)(11)(12), its tendency to cause disease outbreak (13)(14)(15)(16)(17), and its association with antibiotic resistance (12,18). Experimental and clinical evidences suggest a hypervirulent phenotype of Beijing strains (12,19), and a higher mutation rate compared with other strains (20).…”

Expanded Geographical Distribution of the N Family of Mycobacterium tuberculosis Strains within the United States

“…Genotypic analysis of Mycobacterium tuberculosis isolates has been used to confirm tuberculosis (TB) outbreaks (17), to investigate TB transmission in communities (3,24), to identify cases of exogenous reinfection (23), to confirm cross-contamination in the laboratory (10), and to study clonal expansion of strains (14). Clonal expansion has been studied most extensively in the W-Beijing family of M. tuberculosis strains (25).…”