High incidence of drug-resistant Mycobacterium tuberculosis in Hainan Island, China

Prevalence and Patterns of Drug-Resistant Mycobacterium tuberculosis in Newly Diagnosed Patients in China: A Systematic Review and Meta-Analysis

BACKGROUND

Tuberculosis (TB), one of the deadliest infectious diseases globally, is increasingly exacerbated in China by the emergence of resistant Mycobacterium tuberculosis (MTB) strains. Drug-resistant TB, including mono-drug resistant TB, multidrug-resistant TB (MDR-TB), and extensively drug-resistant TB (XDR-TB), presents significant public health challenges.

METHODS

We conducted a systematic literature review from January 2010 to February 2024 using databases such as PubMed, Embase, Web of Science, and Google Scholar. Our focus was on empirical data related to drug resistance patterns in newly diagnosed TB cases. Non-empirical studies were excluded through meticulous filtering. For meta-analysis, we used Review Manager (RevMan) 5.2 and assessed evidence quality using the Newcastle-Ottawa Scale (NOS).

RESULTS

Our search strategy identified 40 studies that met the inclusion criteria, encompassing a total sample size of 87,667 participants. Among new TB cases, the estimated prevalence of MDR-TB in China was 6.9% (95% CI: 5.6-8.1%). Prevalence rates for mono-drug resistance to first-line anti-TB medications were as follows: isoniazid at 18.2% (95% CI: 16.4-20.6%), rifampicin at 10.5% (95% CI: 8.6-12.8%), and ethambutol at 5.7% (95% CI: 4.1-7.3%). The prevalence of streptomycin resistance, a former first-line anti-TB drug, was 17.1% (95% CI: 14.6-19.1%). The prevalence of other types of mono-drug resistance was 15.2% (95% CI: 13.9-17.3%), and for XDR-TB, it was 0.9% (95% CI: 0.6-1.4%).

CONCLUSIONS

The high prevalence of drug-resistant TB in China poses a significant public health challenge. There is an urgent need for targeted interventions and continued surveillance to combat the spread of drug-resistant TB.

Toward tuberculosis elimination by understanding epidemiologic characteristics and risk factors in Hainan Province, China

BACKGROUND

The disease burden of tuberculosis (TB) was heavy in Hainan Province, China, and the information on transmission patterns was limited with few studies. This atudy aims to further explore the epidemiological characteristics and influencing factors of TB in Hainan Province, and thereby contribute valuable scientific evidences for TB elimination in Hainan Province.

METHODS

The TB notification data in Hainan Province from 2013 to 2022 were collected from the Chinese National Disease Control Information System Tuberculosis Surveillance System, along with socio-economic data. The spatial-temporal and population distributions were analyzed, and spatial autocorrelation analysis was conducted to explore TB notification rate clustering. In addition, the epidemiological characteristics of the cases among in-country migrants were described, and the delay pattern in seeking medical care was investigated. Finally, a geographically and temporally weighted regression (GTWR) model was adopted to analyze the relationship between TB notification rate and socio-economic indicators. The tailored control suggestions in different regions for TB elimination was provided by understanding epidemiological characteristics and risk factors obtained by GTWR.

RESULTS

From 2013 to 2022, 64,042 cases of TB were notified in Hainan Province. The estimated annual percentage change of TB notification rate in Hainan Province from 2013 to 2020 was - 6.88% [95% confidence interval (CI): - 5.30%, - 3.69%], with higher rates in central and southern regions. The majority of patients were males (76.33%) and farmers (67.80%). Cases among in-country migrants primarily originated from Sichuan (369 cases), Heilongjiang (267 cases), Hunan (236 cases), Guangdong (174 cases), and Guangxi (139 cases), accounting for 53%. The majority (98.83%) of TB cases were notified through passive case finding approaches, with delay in seeking care. The GTWR analysis showed that gross domestic product per capita, the number of medical institutions and health personnel per 10,000 people were main factors affecting the high TB notification rates in some regions in Hainan Province. Different regional tailored measures such as more TB specialized hospitals were proposed based on the characteristics of each region.

CONCLUSIONS

The notification rate of TB in Hainan Province has been declining overall but still remained high in central and southern regions. Particular attention should be paid to the prevalence of TB among males, farmers, and out-of-province migrant populations. The notification rate was also influenced by economic development and medical conditions, indicating the need of more TB specialized hospitals, active surveillance and other tailored prevention and control measures to promote the progress of TB elimination in Hainan Province.

Analysis of Drug-Resistance Characteristics and Genetic Diversity of Multidrug-Resistant Tuberculosis Based on Whole-Genome Sequencing on the Hainan Island, China

Purpose

Given the high burden of Tuberculosis (TB) in China, the prevalence of multidrug-resistant tuberculosis (MDR-TB) is significant. Whole-genome sequencing (WGS) of Mycobacterium tuberculosis (MTB) enables the identification of lineages, drug-resistant mutations, and transmission patterns, offering valuable insights for TB control, clinical diagnosis, and treatment.

Methods

We collected 202 MDR-MTB strains from 3519 suspected pulmonary TB patients treated at The Second Affiliated Hospital of Hainan Medical University between July 2019 and June 2021. Proportional drug-susceptibility testing was performed using 8 common anti-tuberculosis drugs. Subsequently, the genotypic drug resistance and genetic characteristics were analyzed by the WGS.

Results

Lineages are identified by TB-profiler revealed 202 MDR-MTB strains, showcasing three predominant lineages, with lineage 2 being the most prevalent. Close genomic relatedness analysis and evidence of MTB transmission led to the formation of 15 clusters comprising 42 isolates, resulting in a clustering rate of 20.8%. Novelty, lineage 2.1 (non-Beijing) accounted for 27.2% of the MDR-MTB strains, which is rare in China and Neighboring countries. Regarding first-line anti-TB drugs, genes associated with rifampicin resistance, primarily the rpoB gene, were detected in 200 strains (99.0%). Genes conferring resistance to isoniazid, ethambutol, and streptomycin were identified in 191 (94.5%), 125 (61.9%), and 100 (49.5%) strains, respectively. Among the second-line drugs, 97 (48.0%) strains exhibited genes encoding resistance to fluoroquinolones. Comparing the results to phenotypic drug susceptibility-based testing, the sensitivity of WGS for detecting resistance to each of the six drugs (rifampicin, isoniazid, ethambutol, ofloxacin, kanamycin, capreomycin) was 90% or higher. With the exception of ethambutol, the specificity of WGS prediction for the remaining drugs exceeded 88%.

Conclusion

Our study provides crucial insights into genetic mutation types, genetic diversity, and transmission of MDR-MTB on Hainan Island, serving as a significant reference for MDR-MTB surveillance and clinical decision-making.

Screening and Drug Resistance Analysis of Non-Tuberculous Mycobacteria in Patients with Suspected Pulmonary Tuberculosis on the Hainan Island, China

Background

China has seen a drastic increase in the incidence of non-tuberculous mycobacteria (NTM) infection, which is a notable public health issue. Due to a lack of reliable epidemiological surveillance information, there is a need to gather accurate epidemiological and surveillance data, which can help clinicians effectively treat NTM patients. Moreover, drug susceptibility testing for NTM is not frequently performed in China. This retrospective study, therefore, determined the prevalence and resistance characteristics of NTM to provide a reference to control the NTM epidemic.

Methods

Sputum, alveolar lavage fluid, and other respiratory specimens were collected from 3025 patients with suspected pulmonary tuberculosis attending The Second Affiliated Hospital of Hainan Medical University from January 2014 to December 2021. Strain identification and species distribution of NTM were performed by DNA chip technology and gene sequencing, and the drug resistance of NTM isolates was evaluated by calculating the minimum inhibitory concentration through antimicrobial susceptibility testing for NTM.

Results

From 2014 to 2021, 373 strains of NTM were isolated and identified from respiratory specimens of 3025 suspected tuberculosis patients. Except in 2014, NTM-infected patients accounted for more than 10% of suspected tuberculosis patients in other years. The median age of patients with NTM infection was 62.0 years (53.0, 71.0), and the male-to-female ratio among these patients was 0.79:1. Among culture-positive strains, 12.3% (373/3040; 95% CI 11.1-13.4%) were identified as NTM comprising forty species of NTM. The forty species of NTM included 23 slow-growing mycobacteria (SGM) and 17 rapidly-growing mycobacteria (RGM). Among the NTM isolates, 58.7% (219/373; 95% CI 53.7-63.7%) were SGM and 41.3% (154/373; 95% CI 36.3-46.3%) were RGM. M.avium complex(MAC)(41.3%; 95% CI 36.3-46.3%) and M.abscessus complex (MABC)(33.2%; 95% CI 28.4-38.0%) were the most frequently detected species, followed by M.simiae Complex (11.8%; 95% CI 8.5-15.1%), M.fortuitum group (5.1%; 95% CI 2.9-7.3%), and others. Drug sensitivity test results showed that most of the NTM isolates were susceptible to amikacin and clarithromycin with a drug resistance rate of less than 10%. However, clarithromycin could induce drug resistance, followed by linezolid and moxifloxacin, and their drug resistance rate was less than 50%.

Conclusion

During 2014-2021, the number of NTM isolates detected in the respiratory specimens of the study patients in The Second Affiliated Hospital of Hainan Medical University increased year by year. M. intracellulare is the most common pathogenic NTM species, and there is a high incidence of NTM infection on Hainan Island. Our findings might be of great importance for diagnosing and treating this patient population in Hainan.

Prevalence of Multidrug-Resistant Tuberculosis in Dalian, China: A Retrospective Study

Purpose

Multidrug-resistant tuberculosis (MDR-TB) is the cause of serious health and economic burdens worldwide. The present study aimed to explore the initial and acquired drug-resistance rates among TB patients from 2012 to 2019 in Dalian, China. The effectiveness of MDR-TB prevention and control strategies were then evaluated.

Patients and Methods

Drug susceptibility testing (DST) was performed for 6429 diagnosed, culture-positive, Mycobacterium tuberculosis (MTB) strains, including 4661 new cases and 1768 previously treated cases. Descriptive statistics were employed to calculate the frequencies and percentages of TB strains, and the average annual growth rates (AAGRs) for each strain were calculated. The Chi-square test was applied to examine the significance of linear drug-resistance trends over time during the study period.

Results

Over the eight-year study period, the percentages of both initial (from 9.01% to 4.82%) and acquired (from 40.85% to 9.09%) MDR-TB cases decreased significantly, AAGRs of 8.55% and 19.32%, respectively. Among new and previously treated TB patients, significant downtrends were observed for the rates of both initial and acquired MDR-TB among young and middle-aged individuals (P < 0.05). Additionally, among both new and previously treated TB patients, the percentages of individuals with drug resistance against isoniazid (INH), rifampicin (RFP), ofloxacin (OFX), and amikacin (AMK) decreased significantly (P < 0.05) from 2012 to 2019 in Dalian, China.

Conclusion

The initial and acquired multidrug resistance rates exhibited significantly decreasing trends from 2012 to 2019, suggesting that MDR-TB prevalence has been controlled effectively in Dalian, China. The MDR-TB epidemic was reversed in the short term by establishing feasible strategies for detection, diagnosis, treatment, and infection control.

The effects of family, society and national policy support on treatment adherence among newly diagnosed tuberculosis patients: a cross-sectional study

Background

Non-adherence to tuberculosis (TB) treatment is the most important cause of poor TB outcomes, and improving support for TB patients is a primary priority for governments, but there has been little research on the effects of family, social and national policy support factors on TB treatment adherence. The current study evaluated treatment adherence among newly diagnosed TB patients in Dalian, north-eastern China, and determined the effects of family, society, and national policy support factors on treatment adherence.

Methods

A cross-sectional survey was conducted among newly diagnosed TB patients treated at the outpatient department of Dalian Tuberculosis Hospital from September 2019 to January 2020. Data were collected using a questionnaire that measured medication adherence, family support, social support, and national policy support and so on. Differences between groups were assessed using Chi-square tests and Fisher’s exact tests. Ordinal logistic regression analysis was used to determine the predictors of adherence.

Results

A total of 481 newly diagnosed TB patients were recruited, of whom 45.7% had good adherence, and 27.4 and 26.8% had moderate and low adherence, respectively. Patients who had family members who frequently supervised medication (OR:0.34, 95% CI:0.16–0.70), family members who often provided spiritual encouragement (OR:0.13, 95% CI:0.02–0.72), a good doctor-patient relationship (OR:0.61, 95% CI:0.40–0.93), more TB-related knowledge (OR:0.49, 95% CI:0.33–0.72) and a high need for TB treatment policy support (OR:0.38, 95% CI:0.22–0.66) had satisfactory medication adherence. However, patients who had a college degree or higher (OR:1.69, 95% CI:1.04–2.74) and who suffered adverse drug reactions (OR:1.45, 95% CI:1.00–2.11) were more likely to have lower adherence.

Conclusions

Our findings suggested that non-adherence was high in newly diagnosed TB patients. Patients who had family members who frequently supervised medication and provided spiritual encouragement and a good doctor-patient relationship and TB-related knowledge and a high need for policy support contributed to high adherence. It is recommended to strengthen medical staff training and patient and family health education and to increase financial support for improving adherence.