Worldwide occurrence of Beijing/W strains of Mycobacterium tuberculosis: a systematic review.
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.
London School of Hygeine and Tropical Medicine, London WC1E 7HT, UK. judith.glynn@lshtm.ac.uk
Judith R
JR
Glynn
Jennifer
J
Whiteley
Pablo J
PJ
Bifani
Kristin
K
Kremer
Dick
D
van Soolingen
D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics; D005838:Genotype; D006801:Humans; D009169:Mycobacterium tuberculosis / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D015995:Prevalence; D014376:Tuberculosis / Q000453:epidemiology* / Q000382:microbiology*