Drug resistance between M. tuberculosis beijing family and atypical beijing strains in association with BCG vaccination

A study was implemented to determine the frequency of Beijing family and atypical Beijing, two sub-groups of the Mycobacterium tuberculosis Beijing clade detected in Netherlands, Vietnam, and Hong Kong, and to assess the associations between these strains and patient characteristics. The typical Beijing family isolates were more prevalent than atypical Beijing strains and the former isolated from BCG-vaccinated individuals was also more frequently than the latter. The proportion of Beijing family strains was lowest among the patients aged over 75 years. Furthermore, atypical Beijing isolates were resistant to Isoniazide and several drugs, but less often resistant to Streptomycine than the Beijing family isolates