Challenges in Developing Laboratory Capacity and Infrastructure to Support HIV/AIDS Care Programs

John N. Nkengasong,^a Deborah Birx,^a and Jean-Louis Sankalé^b
aCenters for Disease Control and Prevention, Global AIDS Program, United States
^bHarvard School of Public Health, United States

Laboratory testing for HIV and related opportunistic diseases plays a critical role in the effective implementation of prevention, care, and treatment programs with regard to disease screening, clinical diagnosis, staging of disease, therapeutic monitoring, blood safety, and surveillance. Because of this pivotal role, the overall goal of any laboratory program in a developing country should be to ensure sustainable, integrated laboratory capacity that can provide quality, rapid, accurate, affordable, and reliable diagnostic tests for the effective implementation of lifesaving treatment and prevention programs. However, because of a lack of access to reliable diagnostic testing and an acute shortage of trained staff, coupled with under-resourced laboratory infrastructure in developing countries, inconsistent diagnoses frequently lead to inadequate treatment, increased mortality, and inaccurate determination of the true burden and/or stage of the disease.¹

Since 2003, concerted efforts have been made to provide access to antiretroviral therapy (ART) to the approximately 40 million HIV-positive people residing in developing countries. These efforts include the United Nations–supported Global Fund to Fight AIDS, Tuberculosis and Malaria (GFATM); the World Health Organization (WHO) “3 by 5” initiative, which planned to provide ART to 3 million AIDS patients by 2005; and the U.S. President’s Emergency Program for AIDS Relief (PEPFAR), which has the goal of preventing 7 million new HIV infections, providing treatment to 2 million HIV-positive people living in targeted countries, and providing palliative care to 10 million HIV-positive people. Globally, the current state of laboratories in developing countries cannot support program needs. Indeed, the paucity of functional, quality laboratories—in terms of both human capacity and physical infrastructure—is uniform across most developing countries. Thus, from a public-health perspective, laboratory services must be significantly strengthened and expanded for these well-intentioned efforts to be successful. For laboratory services to be valuable in any program, they must be easily accessible and able to provide accurate and reliable results in a predictably quick turnaround time. The lack of laboratory services was highlighted in a survey conducted in 2000 by the WHO-sponsored African AIDS Vaccine Program (AAVP).² The survey revealed that, as of 2000, fewer than 10 countries in sub-Saharan Africa had the capability to perform HIV-1 RNA viral load or CD4 lymphocyte count testing. A similar survey performed by the WHO African Regional Office (AFRO) found out that although many countries were performing HIV serologic testing, only very few laboratories were enrolled in any form of quality control or external quality assessment (EQA) program.²

In this chapter, we review the multiple challenges that hinder the smooth functioning of quality laboratory services in developing countries and argue that five key areas must be addressed in developing countries in order to develop sustainable public-health laboratories: (1) development of a national strategic plan that emphasizes the need for an integrated approach to disease diagnosis and monitoring—that is, a single laboratory should be able to provide diagnosis and monitoring for HIV/AIDS, TB, malaria, and opportunistic infections (OIs); (2) implementation of an effective tiered laboratory network for referrals; (3) ensuring better coordination of resources and partners in each country in order to avoid parallelism and to strengthen dialogue between research and service delivery laboratories; (4) advocacy for laboratory experts to be represented at all policy levels and during program design; and (5) establishment of a strong quality management system.

Challenges in Providing Reliable Laboratory Services to Meet Program Goals

Finding and Training Laboratory Technicians and Managers

The systemic acute lack of qualified laboratory personnel is a major and severe constraint in implementing and scaling up HIV/AIDS prevention and care programs. In most developing countries, there is a clear correlation between the quality of trained staff and the relative distance from the capital city. National reference laboratories (NRLs) that are situated in the capital city tend to have more qualified staff than do regional or district-level laboratories. The severe lack of trained laboratory experts at the regional and district levels presents an additional layer of challenge in the rapid expansion and decentralization of prevention and care services to district health centers in areas where most of the population resides. To achieve rapid scale-up of services, the training of laboratory personnel is critical at all levels of the laboratory network.

Encouraging results have been reported by WHO AFRO. According to a survey conducted from 2003 to 2005, the number of laboratory staff trained annually in sub-Saharan Africa increased significantly at the district level.² This increase suggests that countries are making substantial efforts to address the issue of the chronic lack of laboratory staff at the district level, in order to meet the huge demand for decentralized services. Training has also involved task shifting with nonlaboratory staff for some HIV laboratory testing services, such as rapid testing at the district level. In fact, nonlaboratory staff, if well trained, can task shift and perform less sophisticated laboratory testing at the district level, thereby allowing more qualified laboratory staff to focus on more sophisticated testing and the implementation of quality control and assurance programs. If appropriate standard operating procedures (SOPs) are established, nonlaboratory staff can be trained to properly and safely collect and handle samples, and either test them or ship them to regional and higher laboratories for complex analyses. The same WHO AFRO survey reported that the total number of nonlaboratory staff trained in HIV laboratory techniques increased from 387 in 2003 to 791 in 2005.²

To address these staffing and training challenges, efforts are being directed to at least three areas: in-service training and the organization of test-specific workshops to meet immediate needs, increasing preservice training that includes curriculum on the full spectrum of testing, and establishing a culture of effective quality management. Advocacy targeted toward universities and other training institutions is needed for effective incorporation of HIV-related content into laboratory curricula. Training must be accompanied by a strategy for recruitment and retention of staff in the public sector. In developing countries, considerable numbers of trained staff are currently being lost to the private sector and to developed countries. In addition, public sector health facilities should also ensure that trained staff members are not redeployed to other job functions where their newly acquired skills are not in use. Because the retention of well-trained laboratory staff is an integral part of total quality management programs, strengthening human resource capacity should be a major goal of building sustainable laboratory capacity.

As training programs are rolled out, it is important that each country develop a program for individual certification that establishes criteria for the successful completion of a standardized training program for both laboratory and nonlaboratory staff. Certification should evaluate trainees based on a written examination and a demonstration of competency in the relevant laboratory techniques. To maintain the integrity and quality of trainees, systems should be put in place for continued on-site monitoring of the competence of trained laboratory and nonlaboratory staff with respect to their ability to follow SOPs, including handing of samples, interpretation of results based on national protocols, and record keeping. Policies are also needed to deal with issues such as certification, training requirements, and necessary qualifications for personnel performing tests. This is especially important for HIV rapid testing and TB smear microscopy.

Providing Reliable HIV Rapid Testing

Reliable HIV testing is the cornerstone for meeting the health goals of prevention, care, and treatment programs in developing countries. To meet these health goals, millions of individuals must be tested for HIV infection, as knowing one’s status is critical to prevention. Since the early 1990s, several rapid tests have become available that detect HIV antibodies in 5 to 30 minutes and, when used correctly in the right algorithm, provide results that are as reliable as results obtained from using a combination of Enzyme-Linked ImmunoSorbent Assays (ELISAs) and Western blot (WB). These tests are less dependent on a cold chain, are easier to interpret, and do not require specialized laboratory personnel and equipment. Moreover, most materials needed to perform the tests are supplied in the test kit. Fairly recently, in response to the increasing need for HIV rapid testing, there has been a proliferation of new rapid tests produced by several companies from around the world. The number of commercially available rapid tests has increased at least fivefold, from an estimated 10 in 1995 to about 50 in 2005. Only 4 rapid tests have been approved by the U.S. Food and Drug Administration (FDA). Several rapid tests have been evaluated in Africa, and many tests have demonstrated sensitivity and specificity comparable to ELISA.^3,4 However, there is a huge challenge in ensuring the quality and reliability of these new rapid tests as well as in ensuring lot-to-lot consistency. This requires a standardized and systematic assessment of the tests’ performance in order to determine their eligibility for use in programs. For this reason, providing appropriate guidelines and testing algorithms to ensure accurate rapid test results has been a priority for several institutions such as WHO and the U.S. Centers for Disease Control and Prevention (CDC). As a first step to ensure that only reliable rapid tests are used in PEPFAR programs, the CDC and the United States Agency for International Development (USAID) have developed a global panel of blood units that are being used to systematically evaluate the quality of rapid tests for use in all PEPFAR-supported countries. Second, the CDC is working with WHO AFRO and other partners to implement postmarket surveillance to monitor the performance of rapid tests once they are in use in the field and to evaluate lot-to-lot consistency. This effort is aimed at ensuring that the quality and integrity of rapid tests are maintained at all times as new lots of tests are released. Third, WHO, the CDC, and USAID have developed a comprehensive training package that provides guidance for the deployment of HIV rapid tests in the field.

In each country, once rapid tests have been deployed, appropriate external quality assurance measures are implemented. These consist of regular site visits, proficiency testing, and the retesting of a small percentage of samples at reference or referral laboratories. However, having enough trained personnel dedicated to site visits to review on-site testing where voluntary counseling and testing (VCT), provider initiative testing, prevention of mother-to-child transmission (PMTCT), and other programs are offered has been challenging in many countries. In addition, most countries lack the capacity to develop a well-characterized panel for use in proficiency testing to monitor the quality and performance of rapid tests at peripheral and district laboratories. The traditional practice of retesting 5% to 10% of samples has not proven practical due to the large numbers of samples currently being tested. For instance, retesting 10% of two million samples in a given country can be very taxing. In some settings, samples have been effectively collected from district and peripheral laboratories and then retested. However, the results have not been returned on time (or at all), thus preventing the tests from serving their intended purpose. This is particularly crucial as many new rapid tests are initially evaluated and approved in laboratories that have well-trained personnel and adequate procedures, and seldom in the peripheral laboratories where their use is intended. New strategies and guidelines to ensure the quality of rapid testing are needed to address these challenges.

Laboratory Clinical Monitoring

As ART programs continue to be scaled up in developing countries, CD4 lymphocyte count testing has become critical in initiating and monitoring response to ART. The lack of access to laboratories capable of performing CD4 count testing has led WHO to recommend using clinical staging to decide whether or not a patient should be initiated on ART. However, clinical staging does not always correspond to the degree of immunosuppression.⁵ Several challenges account for the lack of wider use of CD4 cell counts, even at central laboratories: (1) the high cost of flow cytometry, which is considered the reference method of CD4 cell counting; (2) a lack of skilled laboratory staff; (3) the inability to maintain machines; (4) difficulties in managing the supply of reagents; (5) a lack of reliable point-of-care and easy-to-use machines; and (6) a lack of adequate quality assurance schemes to ensure reliable results. In order to address these critical challenges, simplified non-flow-cytometric CD4 cell counting methods are being developed. Some of the easy-to-use techniques aim to perform CD4 counts on finger-prick blood samples, thus allowing tests to be conducted in the absence of trained phlebotomists or when venous sampling is problematic. A recent small study by MacLennan et al conducted among HIV-positive Malawians showed that the results of absolute CD4 cell counts and percentage of CD4 cell counts were comparable in paired samples collected from finger-prick blood and venous blood.^6,7 If the results of this study are confirmed by others, it may facilitate access to point-of-care CD4 cell count testing at the district level, allowing patients to have same-day test results for both CD4 counts and HIV status.

In general, easy-to-use methods for CD4 testing that have shown promising results need to be validated at multiple sites for accuracy. Such techniques have the potential to make CD4 cell counts affordable and available for use by staff with minimal training at point-of-care sites.^6,7 However, quality control and lot-to-lot consistency must be demonstrated prior to field deployment.

Using Plasma RNA Viral Load to Monitor Patients in Developing Countries

Since 1996, viral load testing has been a key component of standard care in HIV treatment in developed countries. Presently, the target for all treatment, including first-, second-, third-, and fourth-line treatment, is to suppress and maintain viremia at <50 copies/mL.⁸ In developing countries, several challenges exist in using viral load as part of the standard of care. First, current viral load assays are expensive, with the cost per test varying from about US$20 to $100. Performing even one viral load test per year may lead to a several-fold increase in the cost of the cheapest available treatment regimen in developing countries. WHO and other stakeholders therefore do not recommend viral load testing to monitor patients on ART in developing countries. Rather, WHO recommends a public-health approach: scaling up VCT, standardizing and simplifying ART, and monitoring patients’ CD4 cell counts when possible. Despite these recommendations, some treatment advocates have argued that without viral load testing, first-line ART failure may be inappropriately determined based on CD4 cell counts alone, leading to severe consequences, including the need to provide more expensive second-line regimens and the risk of a high prevalence of HIV drug resistance. The benefit of detecting treatment failure by viral load (possible at least six months earlier than by CD4 counts) is therefore valuable not only for the individual patients but also, at the public-health level, for preventing the spread of drug-resistant HIV.

Whether viral load testing will become widely available in developing countries in the coming years depends on the cost and complexity of the test. The WHO 2006 guidelines state that viral load testing may have a role in identifying failure and indicating when to switch medications in some patients.⁹ In addition, WHO supports wider access to viral load testing at tertiary laboratories. To fully address the issue of viral load testing to support the roll-out of treatment programs, cheaper and simpler viral assays are urgently needed. Until then, most treatments in developing countries will continue to be based on an invalidated public-health approach, but a continued push to make these and other technologies accessible to developing countries is necessary.

Some key partners and a number of well-known AIDS clinicians have argued strongly for the inclusion of viral load testing in the treatment of HIV patients in developing countries.^10,11 However, in their present format, viral load tests cannot be deployed on a large scale in developing countries, especially at point-of-care sites. These assays must be performed by technicians well trained in virologic testing methods and require that venous blood be obtained, processed, and transported while frozen to the testing laboratory, with a turnaround time of eight hours. They also require a steady supply of electricity and large amounts of distilled water to run equipment that is usually very costly.

There is a consensus in the field that a suitable point-of-care viral load test should require no more than a finger stick of blood, with a single cartridge for testing and capturing results. The test should not require specimen refrigeration and the equipment should be able to run on batteries, with a cost of less than US$500 to $1,000 per instrument and US$5 to $7 per test.¹² Results should be provided within two hours, and a health worker in the field with limited training should be able to administer the test.¹² Other options include blood draws and stable transport to referral laboratories where testing would not require the current level of sample integrity.

In order to meet the above requirements, it is conceivable that the way forward could be to develop a semi-quantitative test that would indicate the presence of a significant viral load over a certain threshold based on the intensity of a single test line. With this in mind, Dineva and colleagues have developed a prototype test that is based on a dipstick approach, which seems to produce viral load results as efficient as the complex, expensive, and instrument-dependent standard assays.¹³ However, such prototype tests require extensive validation before they can be used for clinical monitoring of patients.

Assays for Toxicity in ART

One of the causes of treatment interruption and subsequent failure among patients receiving ART is the acute and long-term toxicity that many of the drugs can cause. The monitoring of patients on treatment for HIV must also include routine clinical chemistry and hematology tests. Unfortunately, this is also a problem for many health facilities in resource-constrained countries, as very few laboratories are equipped to perform these assays. Guidelines are needed to establish the minimum tests that are required for the proper monitoring of toxicities. Again, the ideal situation for peripheral clinics in resource-constrained settings would be a strip-based assay that would allow simultaneous measurement on one strip for all the necessary tests for ART toxicities monitoring. Such an assay would work on whole blood and be electricity independent. This would be conceptually easier than developing simple solutions for CD4 and viral load testing, as most of these assays already exist in various formats on strips or are amenable to such a format.

Resistance Testing and ART Treatment Programs in Developing Countries

Because of the high cost and complexity of the HIV- drug-resistance assays, most developing countries lack the capacity to perform reliable testing for drug resistance. For example, in sub-Saharan Africa, drug-resistance testing capacity exists in only a few countries, including Cameroon, Côte d’Ivoire, Ethiopia, Kenya, and Senegal. As a consequence, it was clear at the start of the recent scale-up of ART programs that resistance testing would not be included as part of the laboratory test for monitoring patients on ART. Instead, what was implemented was monitoring HIV drug resistance at the population level and developing approaches to reduce its emergence and spread. When WHO launched the “3 by 5” initiative in 2005 to expand access to treatment in developing countries, many critics were concerned that the large-scale use of ART drugs would lead to the occurrence of a drug-resistant HIV epidemic if the antiretroviral (ARV) drugs were not use appropriately. The impact of drug resistance on treatment programs can be enormous, as the transmission of resistant strains can lead to the need to develop new anti-HIV drugs and result in increased direct and indirect health costs. Thus, drug-resistant HIV strains have been recognized as a serious threat to the efficacy of current and future HIV treatment, although it is not clear how rapidly resistant strains will develop.

In countries where ART drugs have been used for many years, the prevalence of resistance among treatment-naïve subjects in several studies varied from 5% to 30%.^14-18 A study carried out in Boston in 1999 showed a prevalence of resistance mutations of 18% in treatment-naïve HIV-positive people.¹⁹ More recently, a study conducted in Nigeria suggested that up to 17% of drug-naïve individuals carry viruses harboring drug-resistance mutations.²⁰ Data from several European countries indicate that 10% of untreated HIV-positive patients had a drug-resistant virus.^21,22 In sub-Saharan Africa, the prevalence of drug resistance in treated populations has been comparable to that reported in Europe and the United States.^23-25

Several major HIV-related public-health issues are being addressed by WHO, including the level of resistance to ART among prevalent HIV strains, changes in HIV-drug-resistance prevalence over time in different areas, and how adherence-enhancing interventions can slow the emergence of resistant HIV strains.²⁶ WHO and its partners have laid emphasis on understanding the key determinants of resistance, especially adherence to treatment and factors that undermine it, while identifying ways to minimize the occurrence, evolution, and spread of drug resistance and providing information to international and country-level policymakers. WHO and PEPFAR are actively involved in the development and implementation of surveillance systems at national and regional levels. These joint efforts aim to measure HIV-drug-resistance prevalence among newly diagnosed and treatment-naïve subjects. Monitoring systems are also being developed and implemented to measure HIV-drug-resistance prevalence among those treated. As part of its support for PEPFAR and WHO, the CDC is currently helping several countries conduct their threshold surveys, including Côte d’Ivoire, Kenya, Malawi, Namibia, Nigeria, Swaziland, Tanzania, Uganda, and Zimbabwe. WHO is establishing and strengthening a global network of experts and laboratories involved in HIV resistance testing and supporting technology transfer in resource-limited settings.

Several ongoing public-private partnerships are also addressing the issue of drug resistance in developing countries. For instance, Virco, a European pharmaceutical company, is actively involved in developing easy-to-use drug-resistance assays that can be deployed in sub-Saharan Africa. This company is a key commercial partner in an exclusive public-private partnership called Affordable Resistance Test for Africa (ARTA), which will receive a grant from the Dutch Ministry of Development Cooperation for the purposes of HIV-drug-resistance technology transfer.

Early Infant Diagnosis

Although WHO estimates that approximately two million HIV-positive people are currently receiving ART in developing countries,²⁷ relatively few infants have received ART. As of 2007, the United Nations Children’s Fund (UNICEF) estimates that the percentage of infected infants in need of ART but currently not receiving it varies from 0.4% in Congo to 18.3% in South Africa.²⁸ Determining the HIV status of infants has proven to be one of the most challenging aspects of PMTCT programs in developing countries. Clinical diagnosis is limited to identifying HIV-positive infants with symptomatic and/or advanced-stage disease and has a low predictive value for ruling out HIV infection in children who are asymptomatic but immunocompromised and in need of OI prophylaxis.²⁹ Infants of HIV-positive mothers acquire HIV antibodies transplacentally and test positive for the presence of antibodies regardless of their actual HIV status. This transplacental transfer of HIV antibodies makes laboratory diagnosis of HIV infection in infants very complex. However, as maternal antibodies decay over time, most uninfected infants become HIV antibody negative by 12 months, and all are negative by 18 months. Thus, before 18 months, virologic tests are the only reliable means of detecting the HIV infection status of infants.²⁹ Nearly 50% of HIV-infected infants under the age of two die before they can be diagnosed and effectively treated.²⁹

Because of the lack of virologic tests in developing countries, access to accurate and timely diagnosis of infants has been a great challenge to the scaling up of early lifesaving pediatric treatment. Virologic tests are expensive and require more sophisticated laboratory facilities. Ensuring the accuracy of these tests for purposes of quality control and assurance is also expensive. More importantly, laboratory technicians specializing in virologic or molecular diagnosis techniques are in short supply in many resource-limited countries. Adequately trained technicians may have high turnover rates, as they are often sought by researchers and by other countries struggling to expand their capabilities.

Other challenges also exist. Phlebotomy of young infants requires supplies and skilled staff that are often unavailable outside large cities. Transport difficulties and distances make it impossible for whole blood samples to reach high-level laboratories in time and in good enough condition for accurate testing. Because of difficulties in returning results quickly to distant clinical sites, staff and mothers may lose confidence in a test and thus reduce its acceptability, while allowing results to go unclaimed. Despite the challenges, however, recent success has been realized using dried blood spot (DBS) nucleic acid polymerase chain reaction (PCR) testing.

HIV DNA PCR and p24 Testing

WHO recommends using HIV DNA PCR testing to diagnose perinatal HIV infection in exposed infants at their first immunization visit at six weeks after delivery. Although several commercial and home-brew methods for DNA PCR testing exist worldwide, the Roche Amplicor HIV-1 DNA test, version 1.5, has been shown to be highly accurate in detecting the multitudes of HIV subtypes that circulate in Africa and is currently being used in many programs across the continent.^30-32

The ultrasensitive p24Ag assay has been used by some groups for early diagnosis of HIV in infants as an alternative to DNA PCR testing. This quantitative assay is based on simpler technology that does not require the detection of the viral genome. Although some studies have shown a sensitivity and specificity comparable to that of HIV DNA PCR, the assay is not yet widely used because more validated studies are needed on its performance in different settings with different subtypes. In a recent study, false-negative DBS p24 results were associated with subtype D; the performance of DBS PCR was 84% for DBS p24 testing, 79% for DBS DNA PCR testing, 85% for plasma p24 testing, and 100% for plasma RNA testing.³³ Easy-to-use point-of-care virologic technologies are needed to support early infant diagnosis in resource-poor countries.

Improved Early Infant Diagnosis Due to DBS Use

DBS use has facilitated access to virologic diagnosis of HIV. Once the blood spots are thoroughly dried and stored with desiccant, nucleic acids in DBSs can be stable for several months at ambient temperatures. This feature of DBSs makes them ideal for transporting specimens from remote rural sites to a central or regional testing laboratory, thus allowing the creation of laboratory networks for early infant diagnosis. Although specimen transport remains challenging, networks of DBS PCR testing laboratories have been established in several countries, some based on the use of volunteers to transport DBS specimens to the nearest PCR testing facility. For instance, a strong laboratory network for DBS DNA PCR testing has been set up in Kenya. In Nyanza Province in western Kenya, 140 DBS collecting sites transport about 500 to 800 samples per month to the CDC-Kenya Medical Research Institute (KEMRI) laboratory in Kisumu for testing. The turnaround time for the KEMRI laboratory to return results to the collection site is two weeks. Similarly, the KEMRI laboratories in Nairobi provide PCR testing support to 37 sites in Central Province, while the Walter Reed Laboratory in Kericho serves 18 sites in Rift Valley Province (C. Zeh et al, 2006, personal communication). In Namibia, DBS PCR testing has resulted in a significant increase in the number of children diagnosed and placed on ART. With the support of PEPFAR, DBS PCR testing has been expanded to several countries within the last three years (Figure 1).

For DBS PCR testing laboratory networks to be effective, the relevant health-care staff must receive specific training in the collection, labeling, drying, and packaging of blood spots to ensure the quality of specimens for virologic diagnosis. Upon receipt at the testing laboratory, specimens must be evaluated by an experienced technologist using SOPs for rejection of samples. If more than 2% of specimens are unsatisfactory, staff at the site should be retrained in collection procedures.

Several challenges still exist with regard to DBS use for early infant diagnosis. As programs expand, one obstacle has been the procurement and distribution of supplies for DBS collection. To meet scale-up needs and ensure consistency, it would be useful to distribute kits containing all the necessary supplies to health facilities. The precise contents of each kit for use in infant diagnosis or quality control of HIV testing would need to be determined individually for each country. Another challenge is the variety of DBS formats, some of which do away with the need for drying racks and separating paper. Because of this variety, it is often difficult for country program managers to determine which formats are appropriate for use. Most countries are currently using the Schleicher and Schuell (S&S) 903 specimen collection paper (Whatman) for DBS collection. An acceptable alternative to S&S 903 paper is Whatman FTA paper. High-volume laboratories may encounter difficulties in testing DBS specimens because extracting DNA from a DBS is labor-intensive and prone to cross-contamination. Further work in automating DBS punching and DNA extraction rather than replicating workstations is needed when testing large volumes of specimens, but with perseverance these programs can be very successful. Approximately 100,000 infants have been tested in the past 12 months and referred for appropriate treatment.

Setting Up Appropriate Quality Assurance Programs and the Need for Laboratory Accreditation

As indicated above, HIV prevention, care, and treatment programs have expanded very rapidly. However, laboratory infrastructure is still lagging behind in terms of the critical components of a quality management system (QMS), which is essential to the improvement of overall laboratory diagnostic services and provides a blueprint for sustainable quality testing. The basic concepts of a QMS must be implemented at all levels of the laboratory pyramid, including quality assurance for the testing process: (1) the pre-analytic phase, which involves competency of personnel, test selection, patient/client preparation, test requisition, correct labeling, transport of specimens, and safety; (2) the analytic phase, which includes specimen processing and storage, reagent preparation, preventive maintenance, quality control, method verification, test performance, proficiency testing, and safety; and (3) the post-analytic phase, which includes reviewing results and quality control, reporting test results and interpretation, and record keeping. In many developing countries, none of these three phases is being properly implemented. To implement an effective QMS, the country must have a laboratory policy that defines the needs and importance of accurate laboratory results. This remains a major limitation and is a gap that must be bridged as programs are scaled up in most developing countries.

In order to ensure that the current increase in resources leads to a significant improvement in laboratory services, standards-based strategies must be adopted in developing countries. This can best be achieved by making laboratory accreditation a critical element of the national laboratory policy and strategy. In sub-Saharan Africa, for example, the few laboratories in Ethiopia, Kenya, and Uganda that are accredited all use external bodies for accreditation and are supported mostly by externally funded research institutions. A standards-based strategy must include the continuing competency of testing personnel, quality management principles, routine audits of laboratory performance, and the customization of international standards that are applicable in-country. Each country could develop strategies and policies for accreditation of laboratories at all levels of the health system and create linkages with regional accreditation bodies that already exist or that could be set up and given the mandate to design regional accreditation schemes. Regional accreditation bodies could be set up along the lines of the existing regional economic communities in Africa, such as the East African Community (EAC), the Economic Community of West African States (ECOWAS), the Economic Community of Central African States (ECCAS), and the Southern African Development Community (SADC).

Supply Management and Equipment Maintenance

In developing countries, it has been a challenge to ensure consistent supply and provision of laboratory commodities to meet the demand created by the rapid scale-up of programs. The timely availability of essential equipment, supplies, and reagents is critical to ensure the overall quality of laboratory testing and avoid disruptions in patient care. A system for the dependable and sustainable acquisition of high-quality reagents and supplies is urgently needed. When PEPFAR was created, USAID established a supply chain management system (SCMS) in order to standardize the procurement and distribution of laboratory commodities to support all PEPFAR countries. Moreover, WHO, the World Bank, GFATM, PEPFAR, the Bill & Melinda Gates Foundation, various countries’ ministries of health, and other stakeholders are working to build consensus on the best way to standardize laboratory commodities across programs and laboratory networks. Standardization of laboratory commodities offers a unique opportunity to coordinate the maintenance of equipment, bulk purchases, training on common instrumentation, and contract services mechanisms. Special attention must be paid to training service maintenance engineers in order to provide a network of biomedical engineers at all levels of the laboratory system. Critical to this aspect is the development of a national laboratory strategic plan that specifies the policies that govern laboratories at each level of a tiered system.

Laboratory Diagnosis of TB and OIs

TB accounts for about two million deaths each year, most of which occur in developing countries³⁴ and are associated with HIV coinfection. Accurate laboratory diagnosis of TB is a challenge in developing countries for several reasons: a lack of trained personnel, inappropriate laboratory working environments, weak or nonexistent external quality assurance measures, a lack of referral systems for patient samples, a limited number of state-of-the-art laboratories to culture and perform drug susceptibility testing, and the creation of stand-alone silo laboratories. In fact, there are only two WHO supranational laboratories in Africa (one in South Africa and the other in Algeria). TB is the most common OI in HIV-positive people, and in some developing countries up to 40% of TB patients are living with HIV.³⁴ Therefore, the need for accurate diagnosis of TB has become critical, especially as ART is being scaled up. Reports have shown that up to 40% of TB patients who are HIV-positive have smear-negative results.³⁵ Moreover, in view of recent reports of extremely drug-resistant TB in South Africa,³⁶ there has been an increased emphasis on strengthening laboratory capacity to diagnose TB in HIV-positive patients and on TB culture. Paradoxically, TB laboratories are some of the most neglected and understaffed laboratories in developing countries.³⁷ However, some major programs such as PEPFAR have placed substantial emphasis on strengthening laboratory capacity to perform TB diagnosis in the context of HIV/AIDS care and treatment. As part of this PEPFAR effort, a regional integrated training laboratory center for HIV, OIs, and TB has been established by PEPFAR in Johannesburg in partnership with the leadership of the South African National Institute of Communicable Diseases (NICD). The NICD training facility will provide hands-on training for laboratory experts in all aspects of TB diagnostics, including smear microcopy, setting up EQA programs, specimen transportation, culture, and drug susceptibility testing. Moreover, this facility will provide integrated laboratory training to meet the needs of HIV, TB, malaria, and OI prevention, care, and treatment programs. Similar PEPFAR partnerships are being developed in other parts of sub-Saharan Africa. Challenges not specific to developing countries, but certainly more acute in resource-limited settings, remain for the diagnosis of TB in infants and young children, largely due to the difficulty of obtaining good sputum specimens from this age group.

Laboratory Information and Management Systems

As programs scale up rapidly, the implementation of laboratory information and management system (LIMS) technologies has become another major challenge. A LIMS is an integral part of a QMS and includes developing simple-to-use systems that allow for the tracking of samples at collection sites during testing and during delivery of the final results to the patients, and the archiving of leftover specimens. All of the above processes may occur in the same local laboratory, or it may be necessary for specimens to be transported across the laboratory pyramid in a network system to a reference laboratory for testing. Regardless of what approach is used, a well-defined laboratory system is needed to ensure proper specimen handling and efficient results reporting.

Because of the difficulties in implementing electronic software at all levels of the laboratory network, standardized, paper-based systems are needed at different levels of the laboratory pyramid in developing countries. In practice, source documents are too often handwritten pieces of paper or books that are sometimes retranscribed several times before reaching a patient or the clinical personnel providing care. This process creates many opportunities for error and resultant losses. In addition, accurate compilation of data for laboratory organization (such as assessment of needs) and for programmatic purposes is difficult.

Modern LIMS technologies have the potential to significantly improve data sharing across tiered laboratory networks in developing countries and to provide timely results at point-of-care facilities. Such technologies should be coordinated and supported—from the national public-health laboratory network to the peripheral laboratories. If such systems are implemented, they will not only improve the quality of clinical laboratory diagnosis but will strengthen the capability to provide epidemic alert and response by recording and analyzing essential laboratory data, maintaining and sharing the data in the laboratory network system in a standardized format, and facilitating frequent exchanges of information and surveillance data with other laboratories within the network and between countries. It will also facilitate a timely flow of information in the laboratory network, which will help inform policy- and decision-making authorities.

In the absence of a LIMS, a computerized system for the management of data, with entry performed directly from source documents, is highly desirable.

Laboratory Automation

Related to data management, it is also important to pay particular attention to the role of automated instruments in laboratory practices. Although the initial cost is high, these instruments often offer considerable reagent savings and allow laboratories to perform a much larger number of tests more reliably. As noted before, this is a more efficient and cost-effective approach than multiplying the number of workstations. The integration of these instruments in a LIMS is easier and increases the reliability of results by reducing human error, both in the performance of the assay and in the transcription of results. Unfortunately, equipment costs, maintenance issues, and operational problems limit the number of laboratories where these systems are feasible. Linking together LIMSs with regional laboratory automated systems enhances the quality of testing.

Infrastructure

In many developing countries, health facilities and laboratories in particular have significant infrastructural challenges. It is common to see facilities with minimal physical infrastructure, with even the physical building being inadequate for the needs of the laboratory. Moreover, laboratories, when they exist, are often in a degraded state. Significant investment in laboratory infrastructure development is desirable in these situations. This requires a concerted effort by government and external donors, preferably within a strategic plan. The chronic lack of clean running water and a stable power supply is an additional challenge that must be tackled while establishing adequate laboratory services and strengthening laboratory networks. Current infrastructure in most facilities also does not allow the development of adequate biosafety procedures in the laboratory and the health facility in general. The lack of proper waste management systems is a crucial problem encountered in many health facilities, where laboratory waste is often disposed of inappropriately, exposing patients, health workers, and the community at large to possibly dangerous infectious waste.

The Way Forward for the Development of Sustainable and Quality Laboratory Capacity

Strengthening Sustainable Laboratory Health Systems through National Strategic Plans with Integration of Diseases in Mind

We believe that to achieve the goal of sustainable laboratory infrastructure and services in developing countries, a well-thought-out and implementable national laboratory strategic plan is indispensable. A well-developed laboratory strategic plan should consider integrating the laboratory work required for at least the three major epidemic diseases: HIV/AIDS, TB, and malaria, such that a laboratory at every layer of the health system can provide timely support for the accurate and reliable diagnosis, monitoring, and surveillance of these diseases, as well as a central national public-health reference laboratory.

Each strategic laboratory plan should address the specific situation of the country and the needs that must be met in order to support health programs and promote in-country capacity building. The plan would provide a platform for coordinating the efforts of all implementing partners and create a framework for advocacy and partnerships at the country level. Such a plan should be based on an integrated approach to laboratory infrastructure development that comprehensively tackles major diseases of public-health importance, such as TB, HIV/AIDS, and malaria. In addition, the plan should be based on a tiered laboratory network, with a strong role for a functional national public-health reference laboratory that is well linked to regional and district laboratory systems, so as to provide effective referral services. The plan should, however, make the effort to take into account and integrate the existing facilities that have been developed prior to the drafting of the plan, so as not to waste resources and the opportunities provided by these facilities. As outlined in Figure 2, the essential elements of an adequate national strategic laboratory plan for an integrated, tiered network include, but are not limited to, the following:

1. Integration of laboratory needs for TB, HIV, OIs, and malaria, including diagnosis, treatment, and prevention. Emphasis should be placed on strengthening laboratory health-care systems that can be used to respond to major infectious diseases of public-health importance. In fact, the current major drivers of disease burden in developing countries are HIV, TB, and malaria; therefore, laboratory capacity developed to address these diseases could invariably be used to fight other disease outbreaks. This approach would shift emphasis away from developing disease-specific laboratories (which are very often difficult to sustain due to a lack of adequate human resources) in favor of an integrated, tiered approach. Such an integrated approach would also allow for cross-training of laboratory staff and provide a unifying approach for EQA and task shifting.

2. Definition of training needs and retention approaches. This should include a well-laid plan for training, with strategic imperatives on preservice, service, and laboratory management adapted for the different laboratory system tiers. Retention strategies should include innovative approaches to improve laboratory-based jobs.

3. Standards and policies for quality of laboratory services. These include guidelines for certification and accreditation of laboratory personnel and services that address issues such as who is allowed to perform testing and at what level of laboratory tests should be performed, as well as guidelines on new technologies and their use in programs.

4. Issues surrounding supply chain management. These include standardization of laboratory commodities and equipment, as well as problems related to the cold chain and maintenance of equipment.

5. Issues relating to laboratory safety and security.

6. A clear framework for working with all funding partners to avoid duplication and parallelism of efforts.

Developing Laboratory Capacity through Tiered Laboratory Network Systems

Strengthening tiered laboratory networks in developing countries is critical to meet program goals. HIV laboratory services should be integrated into general laboratory services (see Figure 3), which is not currently the case in many countries. Often HIV laboratories are either physically separated from routine laboratory services and/or use separate equipment and reagents.

Developing Sustainable Laboratory Capacity by Leveraging Effective Partnerships and Coordination

Since 2002, multiple institutions and bilateral and multilateral programs have continued to provide generous funding to support programs and laboratory services in developing countries. However, generosity may be a burden if it is not well coordinated and managed by capable leadership. In most African countries, it is common for the World Bank, WHO, PEPFAR, the Clinton Foundation, GFATM, and private companies to work with the ministries of health to support laboratory capacity strengthening. If well managed through a national strategic laboratory plan and with coordination at the level of the funding bodies, this support can significantly strengthen laboratory capacity in a sustainable way.

Public-private partnerships could be established between funding bodies and private companies so as to allow them to develop low-cost, accurate, and rapid diagnostic tests that can be used at point-of-care sites to provide same-day results to patients. By eliminating the need for patients to make multiple clinic visits, such tests would significantly improve the ability of patients to be monitored.

An example of leveraging resources is the effective partnership PEPFAR has established through the CDC Global AIDS Program together with four large not-for-profit medical societies that pursue exclusively educational, scientific, and charitable activities: the Association of Public Health Laboratories (APHL), the American Society for Clinical Pathology (ASCP), the American Society for Microbiology (ASM), and the Clinical and Laboratory Standards Institute (CLSI).

APHL provides consultations by senior laboratory professionals who direct or supervise public-health laboratories in the United States. The team members typically have 15 to 20 years of experience in quality laboratory system practice. APHL has the longest-standing laboratory cooperative agreement and is active in Angola, Botswana, Côte d’Ivoire, the Democratic Republic of the Congo, Ethiopia, Haiti, Kenya, Madagascar, Malawi, Mozambique, Namibia, Rwanda, Tanzania, Vietnam, and Zimbabwe. The association has taken on a variety of responsibilities and roles in these countries, but its primary efforts have been in national strategic planning, improvement of the infrastructure for laboratory referral networks, laboratory management training, and laboratory information systems. APHL has established links between state public-health laboratories and in-country services and fostered the training of senior staff as well as the development of local public-health laboratory associations. It has provided regional and country-specific management training to senior laboratory personnel in Ethiopia, Kenya, Namibia, and Zimbabwe, with an emphasis on quality systems management practices.

ASCP, which has a membership of more than 129,000 laboratory professionals, is active in Ethiopia, Guyana, Kenya, Lesotho, Swaziland, and Tanzania. It has also been requested to support in-service training activities in Nigeria and Rwanda. The primary focus of its support to countries has been in-service training in clinical hematology and chemistry. The organization has led in the development of a training-of-trainers (TOT) approach to expanding these services from the federal to district levels in Ethiopia, Kenya, and Tanzania. In Lesotho and Swaziland, it has been integrally involved in strategic planning for public-health laboratory services. In Ethiopia, it is partnering with Joint Commission International to establish national standards for laboratory accreditation.

ASM is the oldest and largest single life science organization in the world and the largest publisher of peer-reviewed professional journals. Consultants are chosen for their technical and cultural expertise from among the society’s more than 43,000 active members worldwide. The partners are currently providing technical assistance in the following areas: laboratory networks, laboratory information systems, accreditation, pre- and in-service training, general microbiology, development of protocols, laboratory management, chemistry and hematology, and quality assurance. ASM is actively supporting programs in Côte d’Ivoire, Kenya, Mozambique, Namibia, Nigeria, Zambia, and Zimbabwe. Its primary focus to date has centered on the enhancement of services for TB and other OIs. In this capacity, the organization is working closely with the ministries of health, WHO, and in-country implementing partners. Its activities include in-service training and infrastructure support for basic microscopy, TB culture and resistance testing, and assistance to countries in strategic planning for laboratory services. In Zimbabwe, ASM is also working with the ministry of health to standardize clinical microbiology protocols on a national scale and expand quality assurance measures at all levels. Work in Kenya, Namibia, and Zambia was initiated during the first year of the cooperative agreement, and activities in Côte d’Ivoire, Mozambique, Nigeria, and Zimbabwe were initiated this year.

CLSI, which writes and distributes guidelines for best practices in the field of medical laboratory testing, is the convener of the ISO’s 52-national-member committee on medical laboratory standards. CLSI has been active in Tanzania and Zimbabwe and has recently started to work in Ethiopia and Nigeria. CLSI is working with countries to align national practices with the ISO’s international standards for laboratory accreditation. In this capacity, the organization is participating in workshops to develop SOPs and train laboratory staff in the documentation of these procedures to be maintained in laboratories. It will continue these activities in both Ethiopia and Nigeria. CLSI is also working with ASCP and Joint Commission International to promote clinical laboratory accreditation by developing a stepwise approach for aligning laboratory standards with ISO guidelines at all service levels in resource-poor settings. This effort is focused on identifying specific steps that can be taken in training, record keeping, specimen handling, and laboratory management at each service tier that will facilitate progress toward accreditation and establish national norms.

Collaborations are also in place with WHO Geneva, WHO AFRO, and the Clinton Foundation. These strong partnerships have led to joint laboratory guidance, including the following:

• Guidelines for Appropriate Evaluations of HIV Testing Technologies in Africa
• Guidelines for Using HIV Testing Technologies in Surveillance
• Guidelines for Assuring the Accuracy and Reliability of HIV Rapid Testing
• Manual for the Laboratory Identification and Antimicrobial Susceptibility Testing of Bacterial Pathogens of Public Health Importance in the Developing World
• A comprehensive training package for HIV rapid testing

PEPFAR also maintains close collaboration with the Clinton Foundation and WHO AFRO to develop guidance on facility-based laboratory management and safe laboratory practices.

Advocacy for Laboratory Experts in Policymaking and Program Planning

Strengthening laboratory medicine in developing countries must be seen as an integral and critical step toward improving overall health-care systems. To achieve this goal, laboratory leaders should be trained and laboratory departments should be created within the ministries of health in developing countries and supported with defined budgets. Strong leadership within the ministries of health will ensure that laboratories do not remain an afterthought in the process of strengthening health systems. Another area that needs much attention is greater laboratory involvement early in the planning stage of program design. Often, laboratory input is sought only after program managers’ planning is quite advanced or near the execution of activities. In addition, due to the complexity and specificity of laboratory activities, infrastructure development, equipment installation, training, and initiation of operations generally require more time than many other aspects of a program. This usually leaves the laboratory lagging behind other components of the program and limits its ability to provide useful insights and contributions.

Conclusion

With increased resources to fight HIV/AIDS and related diseases, laboratories in developing countries are now faced with an opportunity. We can collectively take advantage of the increased resources currently available for global health to expand programs and strengthen laboratory services. A coordinated approach using a national strategic laboratory plan could provide a vehicle for meeting this goal, which would contribute significantly to the development of overall health systems. While directly facilitating the prevention, care, and treatment of HIV disease, better-quality laboratories that are developed to support the roll-out of HIV/AIDS programs can also be important in the fight against other emerging or reemerging infectious diseases and would provide future capacity to support clinical trials for HIV/AIDS, TB, and malaria programs. The increase in resources may present a challenge if efforts are not coordinated, resulting in the emergence of parallel laboratory systems that may lead to the collapse of fragile national laboratory systems and undermine the goal of sustainability. Moreover, if the quality of laboratory services is not improved as quickly as possible, program managers may not see the usefulness of laboratory testing in the overall arsenal of global health protection measures. The key to achieving a sustainable laboratory-strengthening effort is for each country to develop a national laboratory plan that integrates the testing required for the prevention and treatment of all diseases of major public-health importance. Such a national plan will help donors and implementing partners identify where and how to support the ministry of health’s laboratory goals.

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