Worldwide Occurrence of Beijing/W Strains ofMycobacterium tuberculosis: A Systematic Review

Abstract

Strains of the Beijing/W genotype family of Mycobacterium tuberculosis have caused large outbreaks of tuberculosis, sometimes involving multidrug resistance. This genetically highly conserved family of M. tuberculosis strains predominates in some geographic areas. We have conducted a systematic review of the published reports on these strains to determine their worldwide distribution, spread, and association with drug resistance. Sixteen studies reported prevalence of Beijing strains defined by spoligotyping; another 10 used other definitions. Beijing strains were most prevalent in Asia but were found worldwide. Associations with drug resistance varied: in New York, Cuba, Estonia, and Vietnam, Beijing strains were strongly associated with drug resistance, but elsewhere the association was weak or absent. Although few reports have measured trends in prevalence, the ubiquity of the Beijing strains and their frequent association with outbreaks and drug resistance underline their importance.

Extremely high prevalence of multidrug resistant tuberculosis in Murmansk, Russia: a population-based study

“…The SIT1 spoligotype is characteristic of the Beijing/W family, which is known for its frequent association with MDR, outbreaks and high emergence worldwide. The prevalence of Beijing isolates in Russia, both in prisons and in the community, and the high rate of MDR typical for this group have been recognized in a number of studies [5,6,23,[25][26][27]. Our results are consistent with this observation and demonstrate that the Beijing genotype plays an important role in the epidemiology of MDR-TB in civilian population of this high incidence region of the North-Western Russia.…”

“…These strains have been shown to be highly prevalent throughout East Asia and the countries of the former Soviet Union, and have often been associated with community outbreaks, global transmission, and drug resistance [5,6]. The Beijing strains have also been associated with TB treatment failures and relapse cases [7].…”

Identification of the Mycobacterium tuberculosis Beijing lineage in Ecuador

“…More importantly, the Beijing lineage was initially assumed to be associated with resistance, but this association has not been found on a global context. The Ecuadorian sample in the above multinational study included MDR isolates exclusively, and those included in the study corresponded to a single site in Quito (18). In our opinion, including multidrugresistant tuberculosis isolates from only one site severely limited the study.…”

Limited impact of tuberculosis control in Hong Kong: attributable to high risks of reactivation disease

“…silicosis, which is a strong risk factor for tuberculosis [25], was the second most commonly notified occupational disease during the 1990s in Hong Kong [26]) ; or the pathogen itself (most of the isolates of M. tuberculosis found among Asian tuberculosis cases belonged to the Beijing family of strains [27,28], although its association with the risks of developing disease remains unclear). Elucidation of the relative contribution of these factors to the high disease risks requires further studies.…”