Nearly half of patients diagnosed with multi-drug resistant tuberculosis (MDR-TB) at a Chinese hospital had not had the disease before, showing “‘substantial’ transmission of the deadly superbug,” according to a study conducted by researchers from the Chinese Center for Disease Control and Prevention and published in the journal Emerging Infectious Diseases, Bloomberg reports.

Many of the 45 of 100 MDR-TB patients were diagnosed with “the so-called Beijing genotype, which is prevalent in China and has spread to the rest of Asia, the former Soviet republic and South Africa,” the news agency writes. “Most of the patients in the study were previously treated, lacked health insurance, or less educated, according to the study,” according to Bloomberg, which notes China records the second highest number of TB cases worldwide after India (Khan, 9/29).