Surveillance of anti-tuberculosis drug resistance in the world: an updated analysis, 2007-2010

Objective To present a global update of drug-resistant tuberculosis (TB) and explore trends in 1994-2010. Methods Data on drug resistance among new and previously treated TB patients, as reported by countries to the World Health Organization, were analysed. Such data are collected through surveys of a representative sample of TB patients or surveillance systems based on routine drug susceptibility testing. Associations between multidrug-resistant TB (MDR-TB) and human immunodeficiency virus (HIV) infection and sex were explored through logistic regression. Findings In 2007-2010, 80 countries and 8 territories reported surveillance data. MDR-TB among new and previously treated cases was highest in the Russian Federation (Murmansk oblast, 28.9%) and the Republic of Moldova (65.1%), respectively. In three former Soviet Union countries and South Africa, more than 10% of the cases of MDR-TB were extensively drug-resistant. Globally, in 1994 to 2010 multidrug resistance was observed in 3.4% (95% confidence interval, Cl: 1.9-5.0) of all new TB case's and in 19.8% (95% Cl: 14.4-25.1) of previously treated TB cases. No overall associations between MDR-TB and HIV infection (odds ratio, OR: 1.4; 95% Cl: 0.7-3.0) or sex (OR: 1.1; 95% Cl: 0.8-1.4) were found. Between 1994 and 2010, MDR-TB rates in the general population increased in Botswana, Peru, the Republic of Korea and declined in Estonia, Latvia and the United States of America. Conclusion The highest global rates of MDR-TB ever reported were documented in 2009 and 2010. Trends in MDR-TB are still unclear in most settings. Better surveillance or survey data are required, especially from Africa and India.