Laboratories continue to play an important role in disease control and prevention programmes through the provision of timely and accurate information for use in and disease surveillance patient management. In line with Zambart’s mission and objectives, the Zambart Laboratory Unit is organised to directly assist the organisation in fulfilling its mandate to influence public health policy through research and improving health research capacity in Zambia.
The Zambart laboratories consists of the Central Laboratory situated at Zambart House and consists of a biosafety level 3 TB laboratory and 5 Regional laboratories in 5 towns along the line of rail. Two of the Regional labs (Livingstone and Kabwe) are housed in container labs, while three are embedded within the main hospital laboratory (Choma, Kitwe, and Ndola). In addition, as part of the TREATS project, Zambart has two mobile labs which consist of a truck with both laboratory and digital x-ray facilities.
The Zambart laboratory has the capacity to perform TB culture processing, molecular testing, rapid tests and fourth generation testing for HIV and other immunological tests, CD4 Counts, GeneXpert assays such as Xpert MTB/ RIF Ultra and HIV viral load, plasma processing, QuantiFERON® TB Gold-Plus for TB infection, and microscopy. The Central laboratory is also equipped with a repository containing several ultra-low temperature freezers for long-term storage of samples.
Some of the activities carried out include the following:
TREATS Infection Cohort
Participant blood samples collected in the field and sent to the lab were incubated, processed and plasma stored in freezers at -80°C at both Zambart Regional Laboratories and Zambart Central Laboratory. All frozen plasma aliquots from regional laboratories were shipped to Central laboratory for QuantiFERON® TB Gold-Plus (QFT-Plus) ELISA assay testing once a month using a supplies truck which has battery-powered freezers installed to enable the shipping of frozen samples. The QFT-Plus ELISA assay is a test done on blood products to test for latent TB infection.
Data capture for all specimens received is done centrally in a sample registration database at Zambart House. QFT-Plus ELISA test results that had been quality controlled (Qced) and verified were imported from the lab on to a shared drive for the data team to extract and link with field data and proceed with subsequent analysis
TREATS TB Prevalence Survey
National TB Drug Resistance Survey
Recruitment of participants for TB DRS commenced on 27th September 2019 and is expected to run for twelve months.
Two sputum samples submitted from each survey participant are transported to the Zambart Central lab from the 47 randomised TB Diagnostic Centres across the country via a dedicated Courier system. The sputum samples are tested for TB disease and drug resistance first using which is a faster way of testing for TB disease and Rifampicin drug resistance. The samples are then subjected to TB culture processing for further identification of the disease causing agent and drug resistance; testing for not only Rifampicin, but also other TB drugs which include Isoniazid, Ethambutol and Streptomycin.
Decontaminated sediments and cultures identified as positive for TB are stored in the freezer at -20°C. Some of the stored samples with identifiable drug resistance are to be subjected to sequencing at a later stage, and some will be sent to the Uganda Supranational Reference Laboratory (SRL) for EQA.
Zambart Central Laboratory has embarked on attaining laboratory accreditation according to ISO15189, and engaged in quality manual training, compliance and implementation activities. The process is expected to take 24 months to final accreditation is achieved.
The Laboratory is also involved in annual Proficiency Testing activities for different lab assays and tests performed at Zambart Central lab. Testing panels are received from the College of American Pathologists (CAP) and Uganda Supra-National Reference Laboratory (SRL).