Declining prevalence of multidrug-resistant but comparatively high quinolone-resistant tuberculosis in Heilongjiang Province, China: 2013–2022 trend

The spread of multidrug-resistant tuberculosis (MDR-TB) remains a major problem globally. China is the high-burden country for TB, TB/HIV and MDR/rifampicin-resistant TB (RR-TB) in the period 2021–2025. Heilongjiang Province, located in the northeast of China and is the border region with the Russian Federation, which is also a high-burden country for TB/HIV and MDR/RR-TB. Heilongjiang Province had a higher prevalence of TB and MDR-TB than many other areas of China based on data 2007–2012(Li D, et al. BMC Infect Dis. 2016.16:516). The high prevalence may affect the epidemic of TB and drug-resistant TB in China as well as in Russia. Therefore, the knowledge about the patterns of drug resistance in this TB high-burden area of China is crucial to develop appropriate control strategies. This study is a continuation of an analysis of the drug-resistant TB epidemic in this area, 2013–2022. A total of 11,139 Mycobacterium tuberculosis (M. tuberculosis) clinical isolates were collected from 11,139 hospitalized patients with TB from 2013 to 2022. The sensitivity of the isolates to first- and second-line antituberculosis drugs was investigated. We also compared the two methods for drug susceptibility testing (DST), including absolute concentration and liquid rapid culture. The prevalence of drug-resistant TB to any first-line drug and second-line drug was 38.9% and 31.0%, respectively. The prevalence of MDR-TB (8.5% in 2013–2022 vs. 22.8% in 2007–2012) has significantly declined. However, the prevalence of levofloxacin(Lfx)-resistant-TB (13.5% in 2013–2022 vs. 10.4% in 2010–2012) has increased. The trends of resistance to the first- and the second-line drugs in 2022 slightly increased compared to those in 2020 and 2021. The prevalence of pre-extensive drug-resistant TB (pre-XDR-TB, resistant to rifampicin and any of fluoroquinolones) was relatively high (7.6%). The maintenance of a high prevalence of fluoroquinolone-resistant and pre-XDR-TB remains a serious threat to public health and has an impact on TB control to achieve China’s goal of TB elimination. Therefore, continuous surveillance of the spread of drug-resistant TB in this border region is important.