The Centre for Tuberculosis (CTB) was established in 2012. It was formerly known as the National TB Reference laboratory which was incorporated into the CTB with broader functions. In line with the mandate of the NICD, the CTB conducts laboratory-based public health surveillance of TB in South Africa. It continues to serve as a National TB reference laboratory (NTBRL) and was endorsed by the World Health Organization (WHO) as a supranational reference laboratory in 2016.
Global TB policies and guidelines are initiated through WHO and their formulation has included representation from the CTB which assisted in developing these strategic documents.
The objectives of CTB are:
- To conduct laboratory-based public health surveillance for drug sensitive TB, drug resistant TB and new drugs for the treatment of TB;
- To provide specialized reference mycobacteriological services to South Africa and the African continent;
- Apply innovative techniques such as next generation tools to improve the diagnosis and treatment of TB and drug resistant TB;
- To initiate applied public health research aimed at providing enhanced intelligence on the drivers and protective factors that underlie the TB epidemic in South Africa; and
- To advise and work closely with the Department of Health on strategic planning of the national TB program and formulate guidelines and policies for the diagnosis and treatment of TB in South Africa.
The first-ever South African National TB Prevalence survey was a collaboration between the MRC, HSRC, NICD and NDoH. The survey aimed to establish the true burden of pulmonary TB disease in South Africa and was conducted according to the international recommendations of the WHO Global Task Force on TB Impact Measurement. The Centre for TB (NICD) was tasked with providing the laboratory services for the survey. Cases of presumptive TB were detected through an initial screening for TB symptoms and chest X-ray (CXR) of all eligible individuals, and a subsequent bacteriological examination of two sputum samples per individual. All sputum samples were processed for Xpert MTB/RIF Ultra and liquid TB culture. This was one of the first TB prevalence surveys to use the Xpert MTB/RIF Ultra for TB case detection. Findings from the survey were used to develop an algorithm for the management of patients with Xpert ‘Trace’ result. See section ‘’Advancing Diagnostics, Epidemiology and Treatment’’ for the algorithm.
The CTB conducts and supports other countries to undertake population based survey and research to enhance our understanding of the disease burden and factors impacting on efforts aimed at controlling and eliminating TB and DR-TB. These are aimed at informing policy and practice.
Public Health Surveillance plays a critical role in informing and directing health responses and is a key activity of the CTB. Time series analysis is an important tool applied to monitor success or failure. Additional geospatial analysis is applied to define the epidemic and guide responses.
The centre serves not only as the NTBRL for South Africa, but also as the supranational reference laboratory in Africa. The services provided address complex clinical cases as well as programmatic support and quality assurance to laboratories locally and globally.
Treatment of drug resistant TB has evolved over the last couple of years with new and re-purposed drugs being included in the treatment regimens. The CTB performs drug susceptibility testing for the following new drugs: Bedaquiline, Clofazimine, Linezolid and Delamanid and monitors resistance to these agents.
Early detection ensures that correct treatment is instituted earlier aiding in the control of drug resistant TB.
Innovations are the key to success and the CTB has prioritised this aspect. This advancement is aimed at developing and evaluating novel approaches to improving diagnostic and treatment landscape for TB and DR-TB. The use of next generation technologies has expanded the horizon in addressing challenges with TB control and has been well established at the centre. Understanding transmission and latency are the other core themes being pursued at the CTB.
LEADERSHIP AND TEAM
Dr Farzana Ismail is a Clinical Microbiologist and worked initially as consultant at a tertiary level Microbiology laboratory attached to the Steve Biko Academic Hospital and provided specialist services in both infectious diseases and infection control. These services extended to regional and district hospitals covering the Northern region of South Africa.
She is a senior lecturer at the University of Pretoria involved in training medical undergraduate and postgraduate students as well as registrars in clinical microbiology and infection control. In 2017, she was appointed as the pathologist at the Centre for tuberculosis and now leads the WHO Supranational TB Reference laboratory section of the Centre providing support to other National TB reference laboratories in the region as well as conducting an external quality assurance program for high burden TB reference laboratories in Africa. She has a keen interest in drug resistant TB, diagnostic technologies, and patient centred care for TB. An important initiative has been reference laboratory support to clinicians managing difficult to treat and highly resistant TB patients in SA. She also plays an important role in surveillance activities trying to monitor new drug resistance as well as patient pathways to TB diagnosis among drug susceptible TB.