Prevalence of drug-resistant tuberculosis and associated risk factors among patients in the Northern Region of South Africa

M.Sc. (Microbiology)

Department of Biochemistry and Microbiology

Background: Drug-resistant TB is a major global health threat, driving the ongoing TB epidemic and increasing morbidity and mortality worldwide. Currently, national tuberculosis (TB) control programmes are challenged by the emergence of drug resistance to more anti-TB drugs resulting in multi-drug resistant TB (MDR-TB), pre-extensively drug-resistant TB (pre-XDR-TB) and XDR-TB. Globally, about 465,000 people have rifampicin-resistant TB (RR/TB; 78% MDR-TB), where new cases contribute about 3.5%, and 18% among previously treated cases. Variety of factors, including demographic, behavioural, clinical, and environmental factors can favour the spread of DR-TB in the community. However, the major mechanism of acquiring DR-TB is through the spread of drug resistance (DR) mycobacterial strains in the community. Individuals who have had contact with someone who has drug-resistant TB are more likely to contract the disease. As a result, assessing the major associated risk factors contributing to the emergence of DR-TB using data from the local setting is critical in order to take appropriate action. Objective: The study aimed to investigate the prevalence of drug-resistant tuberculosis and associated risk factors among TB patients from health care facilities in the Northern Region of South Africa. Methodology: In order to determine the prevalence of drug-resistant TB and associated risk factors, this investigation adopted a cross-sectional study design. The study enrolled 50 tuberculosis patients of age 18 years and older from healthcare facilities in the Vhembe region between August 2022 and August 2023. Patients undergoing active TB treatment were recruited as participants in this study. Data on demographic characteristics, comorbidities, healthcare-seeking behaviour, TB-related stigma, and adherence to infection control measures were collected using a detailed questionnaire. Allplex™MTB/MDR/XDR assay (Multiplex PCR) was used for rapid detection of M. tuberculosis and drug-resistant TB. To study the association between risk factors and development of drug-resistant TB, Rstudio was employed (a statistical analysis software package). The chi-squared method was used to determine whether the association between two qualitative variables were statistically significant among the study population. Results: Among the 50 sputum samples that were collected for the study, 17 (34%) remained TB active. Of these, 13 (26%) did not develop any resistance and the remaining 4(8%) presented drug-resistant TB strains which were resistant to at least one or more anti-TB drugs. There was an equal distribution in terms of gender. Four percent (4%) of the female cases had mono-resistant TB, of which 1(2%) was isoniazid resistance (INH) and the other one being 1(2%) rifampicin resistance (RIF). Furthermore, 4% of the male cases had Extensively drug-resistant TB (XDR-TB), showing resistance to rifampicin (RIF) + isoniazid (INH) + fluoroquinolone (FQ). Having HIV infection (P=0.042), unemployment (P=0.023), non-adherence to TB treatment (P=0.042), smoking habit (P=0.023), history of contact with DR-TB patient (P=0.023) and history of previous anti TB treatment (P=0.023) were found to be significant factors for the development of drug resistance. Other factors such as age (P=0.127), gender (P=0.127) and education (p=3.246) were not significantly associated with drug resistance TB. Conclusion: This study showed a low prevalence of drug-resistant TB in the Vhembe district with factors such as history of TB treatment, close contact with drug-resistant TB patients, non-adherence to TB medication, HIV infection and tobacco smoking, showing a significant association with drug-resistant TB. Hence, the study recommends that these factors must be taken into account in the planning and development of drug-resistant TB policies in order to work successfully towards the achievement of sustainable development goal of reducing TB by 80% before 2030. This study also highlighted that drug-resistant TB was more prevalent among the young and economically active age groups (20-40 years) than older individuals. Even though the prevalence of drug-resistant TB in this study was considered low, these findings highlight the need for health education efforts to strengthen accurate information to improve TB knowledge and correct misconceptions about TB among patients within the community especially the young age group.

National Research Foundation (NRF)