Growing drug resistance
According to the report, approximately 20% of TB cases globally are estimated to be resistant to at least one of the first- or second-line anti-TB drugs, and 5% are resistant to both isoniazid and rifampicin, the most powerful and commonly used antibiotics in first-line treatment. Of the estimated 480,000 cases of multidrug-resistant (MDR) TB, approximately 10% are either extensively drug-resistant (XDR)—with additional resistance to second-line drugs—or totally drug resistant.While TB is curable when patients adhere to the treatment regimen, MDR- and XDR-TB are more problematic. Treatment options are limited, expensive, and often toxic, and drug therapy can last up to 2 years. The report estimates mortality rates of around 40% for MDR-TB and 60% for XDR-TB. And while China, India, Russia, and South Africa have the highest burden of MDR- and XDR-TB, widespread international travel and migration means drug-resistant TB has no borders.Although shorter treatment regimens and new drugs are providing hope for some MDR- and XDR-TB patients, the authors of the report say the fight against drug-resistant TB has to be fought on several fronts. “Addressing drug-resistant tuberculosis requires an urgent and concerted effort to manage the disease and prevent onward transmission with sustained research to develop and assess new tools,” the authors write.