Tuberculosis continues to be a public health burden with estimated incidences having risen six fold with the advent of the HIV epidemic in Zambia. Delayed diagnosis and the lack of sensitive but affordable diagnostic tools are two of the various challenges that the fight against TB in Zambia faces .In response to these challenges the World Health Organization has recently recommended the use of a new diagnostic tool, the GeneXpert MTB/RIF for diagnosis of TB. In making these recommendations, it was recognised that further evaluation studies were still needed particularly in resource poor high burden countries where this new tool is most likely to have the most impact if adopted.
This study will inform the Zambian National TB (NTP) program as well as international policy makers on the impact of using the GeneXPert MTB/RIF in a typical resource poor high TB HIV burden setting. This study will further contribute knowledge on the best algorithm to use for accessing diagnosis with the GeneXpert MTB/RIF as well as contribute knowledge towards a treatment monitoring system when using this new assay.
To detect and successfully treat more cases of accurately diagnosed TB through health systems and community systems strengthening and to determine, through operational research, the efficiency, treatment monitoring system and cost effectiveness of two GeneXpert algorithms for TB diagnosis
The study protocol has been approved by the ethics committee of the University of Zambia.
A combination of study designs will be used to conduct this study. The main study will be a prospective descriptive study of the use of GeneXpert in a resource limited setting testing to algorithms for accessing diagnosis with geneXpert (See Flow diagram below). Nested within this study will be cross sectional study that will include a cohort of patients. Information collected from this cross sectional study will be used to determine the treatment monitoring system for GeneXpert and determine the effect on outcomes of TB patients when GeneXpert is used as well as factors that best predict GeneXpert positivity and thus inform on algorithm design.
The study population will be made up of persons living within the community who will be targeted for Enhanced Case Finding (ECF) messages.
Any person of any age who meets definition of TB suspect is able to submit a sputum sample
Any persons that do not meet the definition of a TB suspect
Pregnant women will be excluded where the algorithm uses CXR as entry point for diagnosis
The cohort will have three follow up visits and tests done at every visit include a CD4 count, FM smear, culture and GeneXpert done.
Lead Team: Dr. Monde Muyoyeta (Principal Investigator), Dr. Helen Ayles (Investigator), Dr. Nathan Kapata (Investigator), Ms. Maureen Moyo (Investigator)
Monde Muyoyeta, PhD, is an infectious diseases epidemiologist. She is Head of Diagnostics studies Unit at Zambart, and an investigator on a TB vaccine trial, a phase II b clinical trial.
Monde Muyoyeta, PhD ZAMPACT/TB Reach Study Manager
Monde has over 9 years of experience conducting research in TB and HIV in high burden settings, and has been involved in various studies including the ZAMSTAR study, a large two-country randomised control trial of community level interventions aimed at reducing the burden of TB and HIV. Recently, she was investigator on a World Health Organisation (WHO) funded implementation evaluation study on the use of Xpert MTB/RIF in primary health care facilities in resource constrained settings. This study also evaluated the use of Computer Aided Diagnosis (CAD) for electronic scoring of digital chest x-rays for diagnosis of TB.
She holds a Bachelor of Science, Human Biology and Bachelor of Medicine and Bachelor Surgery from the University of Zambia. She also has a PhD from the London School of Hygiene and Tropical Medicine. Her research interests include implementation evaluation of new diagnostic technologies with specific bias to TB and HIV diagnosis, TB control and prevention.