To accelerate global tuberculosis efforts, the World Health Assembly approved the End TB Strategy⁹ in 2014 as a 20-year strategy with the vision of a ‘world free of TB’ and the goals of ‘zero deaths, disease and suffering due to TB’.² The strategy’s milestones and targets are ambitious: by 2025, there should be a 75% reduction in tuberculosis deaths and 50% reduction in new tuberculosis cases, and by 2035, there should be nearly no deaths from tuberculosis and a 90% reduction in new tuberculosis cases. The Global Plan to End TB 2016–2020 was developed concurrently by the Stop TB Partnership as a costed plan to implement the End TB Strategy and provide a path for policy makers to achieve the Strategy’s milestones, including a roadmap for new diagnostics.¹⁰ Both the End TB Strategy and Global Plan clearly articulate that countries must design and implement diagnostic services that promote early and rapid diagnosis of tuberculosis and MDR tuberculosis by using new technologies and expanding the pool of people to be tested. It is fully expected that countries will provide universal DST to all people with tuberculosis. Africa must use the opportunities within both the Strategy and Global Plan and translate them into interventions to improve diagnostic services.

Compared to a few years ago, laboratory services in Africa now have better access to advanced tuberculosis diagnostics, including the rapid molecular assays that can accurately diagnose tuberculosis and drug-resistant tuberculosis in less than a day, improved sensitivity for microscopy through fluorescent light-emitting diode technology and faster automated liquid tuberculosis culture systems. Recent advancements in diagnostic tests to detect HIV, including advanced point-of-care rapid diagnostic tests, early infant diagnostic tests and viral load tests, are all critically important in Africa as part of the continuum of care for people co-infected with tuberculosis and HIV.

Laboratory quality management and accreditation systems are now available, including the Strengthening Laboratory Management Towards Accreditation and Stepwise Laboratory Improvement Process Towards Accreditation tools developed especially for Africa.¹¹ Other enabling e-tools for tuberculosis diagnostics are increasingly made available, including: software platforms that transfer diagnostic outcomes and testing information in real-time to tuberculosis programme officers, clinicians and health workers; commercial specimen transport solutions that can reduce the potential for culture contamination; and mapping technology to allow the visualisation and overlay of all diagnostic networks in a country and the ability to optimise integrated networks in response to existing and future diagnostic algorithms.

The data above suggest that increasing the number of laboratories may improve access to tuberculosis diagnostic services to an extent. However, it may not necessarily increase overall tuberculosis case notifications under programmatic conditions. Enabling interventions such as appropriate changes in national diagnostic policies and algorithms, adequately resourced ambitious strategic plans, increased training for human resources, efficient sputum transport systems to avoid unnecessary diagnostic- and patient-delayed testing, and increased participation of community level organisations are all needed. The need for early access to point-of-care diagnostic services and treatment monitoring is greatest at the primary healthcare level and at the community level, whereas more sophisticated extensive diagnostic capacity is needed at regional- or central-level facilities.¹² Suboptimal linkages with clinical services in many countries often result in either no diagnosis or diagnoses without treatment initiation or delayed treatment, which in turn lead to poor treatment outcomes, including death. It is expected that with increased electronic connectivity between new and emerging molecular diagnostic tools and treatment centres, the diagnostic-treatment gap will diminish significantly and clinical outcomes will improve.

To address the deficiencies in laboratories’ diagnostic capacity, the integration of public health laboratory networks and surveillance systems¹³ for infectious diseases remains an urgent requirement. This need became clear during the recent Ebola outbreak in West Africa, which had a devastating socioeconomic impact on the countries affected,¹⁴ as well as on their public health systems.¹⁵ Well-designed, integrated systems would also meet the need for the implementation of the International Health Regulations¹⁶ and be in line with the Global Health Security Agenda with its current efforts to promote global health security as an international priority.¹⁷ Integrating laboratory services under one roof would be enhanced by networking with adjunct public health institutions, disease-specific referral laboratories and centres of excellence, facilitating systematic engagement of all governmental and non-governmental health structures. It is envisaged that linking the capacity to detect and manage MDR and extensively-drug-resistant tuberculosis to both the Global Health Security Agenda and the recently forged Declaration on Combating Antimicrobial Resistance will strengthen control of MDR and extensively-drug-resistant tuberculosis globally.

Strengthening collaborative tuberculosis/HIV activities (i.e., an integrated approach for prevention, diagnosis, and treatment among co-infected patients) will remain critical in addressing the tuberculosis/HIV epidemic in sub-Saharan Africa. Integrated laboratory services under one roof have the potential to reduce repeated visits of patients to health facilities by comprehensively screening for multiple infectious diseases, thus improving early case detection and management, in addition to optimising the use of laboratory resources. The fast-growing transition toward more non-communicable conditions in most settings can be tackled through integrated service provision. By default, several laboratory facilities at the district level in Africa provide ‘integrated services’, in one form or other, due to resource constraints and sharing of facilities and personnel. The challenges are mainly related to inadequate infrastructure, equipment, skilled laboratory personnel and their mentoring and supervision, resulting in inadequate integration. The integrated approach demands systematic training and recruitment of high-quality and skilled laboratory scientists, technologists and other laboratory personnel. To achieve universal health coverage, as set out in the End TB Strategy, interdependent, fully-integrated laboratory networks at the country and regional levels are needed, with a minimum set of diagnostic technologies for key infectious diseases prevalent at district and subdistrict levels.

A persuasive way to enhance diagnostic capacity is through the establishment of regional laboratory networks. The capacity of national reference laboratories for culture and drug resistance testing in many African countries has been developed through several multi-country collaborative efforts, such as the EXPANDx-TB project and the East African Laboratory Network, established by the World Bank and aimed at setting up cross-cutting laboratory services with a clear surveillance focus. These networks have been playing an increasingly critical supportive role in the diagnosis and management of drug-resistant tuberculosis.

The strengthening of laboratory systems should be further facilitated through new African regional collaborative initiatives across intergovernmental health bodies and communities. Regional health networks have an important role in facilitating adoption and adaptation of global policies and allowing better care and surveillance through increased domestic funding commitments within the region. The East Central Southern African Health Community regional tuberculosis laboratory networking supported by the Global Fund is one example of the right direction in this regard.

Key components of the End TB Strategy are the early and rapid diagnosis of tuberculosis, universal DST, and systematic screening of contacts and people who practise high-risk activities.¹⁶ Research across the continuum from basic to new tool development and operational research is an essential requirement of the End TB Strategy and should be strengthened, especially in Africa. The existing laboratory and diagnostic systems at various levels in Africa would greatly benefit from increased resource mobilisation for, and participation in, the development of new tuberculosis point-of-care diagnostics, shorter treatment regimens and, ultimately, an effective vaccine by 2025. While new rapid diagnostic technology has become increasingly available, further scale up must be informed through well-designed operational assessments, including the integration of testing platforms across diseases and with diagnostic algorithms employed in other diseases. African-specific operational research is needed to improve many components of the diagnostic network, including linkages from diagnostic to treatment centres, ideal testing algorithms for country-specific settings, expanding skills and capacities of laboratory technologists, operational requirements for technologies at the facility level, such as quality electricity supply, adequate logistics for diagnostic commodity procurement and distribution within the country, effective integrated sample transport networks and timely feedback of results.

While concerted action from all stakeholders is needed, national governments must demonstrate stronger political will and provide stewardship. Efforts must be enhanced to ensure that diagnosis and treatment systems for tuberculosis and drug-resistant tuberculosis are available and well aligned across the different levels of their public health systems. Lower-level laboratories must be linked to higher-level laboratories for access to follow-up testing for efficient patient management, ensure optimal use of different technologies at different levels of the tiered network, and maintain staff competence in these techniques.¹² Ministries of Health should ensure that national medical laboratory strategic plans – either as stand-alone documents or as part of national tuberculosis strategic plans – are put in place and implemented. Strategic oversight at the country level should continuously ensure the effective management of laboratories, the quality of testing, and the efficient use of the network’s tuberculosis diagnostic services.

Tuberculosis laboratory services and networks suffer multiple deficiencies in Africa. Implementation of rapid molecular diagnostic laboratory tools for tuberculosis in the past five years, has resulted in an increased number of people diagnosed with and treated for drug-resistant tuberculosis in Africa, although drug-sensitive tuberculosis cases and tuberculosis/HIV cases have not seen increased case notifications, primarily due to restricted diagnostic algorithms, and capacity and access limitations. There is an urgent need to redefine the purpose, structure and optimal use of diagnostic networks to diagnose tuberculosis within the resource-constrained setting of Africa and tuberculosis epidemiology. Well-planned and -resourced national strategies are needed to achieve the laboratory targets set forth by the Global Plan to strengthen services toward ending tuberculosis. Appreciable efforts made in the introduction of new laboratory technologies in the last five years in several countries need to be multiplied at all service delivery levels to maximise technology utilisation to close the diagnostic gap in providing universal access to tuberculosis DST by 2020 in Africa. Integration of laboratory services within public health institutions and public–private collaborations would improve tuberculosis case detection. Tuberculosis is preventable, treatable and curable, and governments need to swiftly demonstrate strong leadership in ending tuberculosis as a leading infectious disease in Africa.