Evaluating urban-rural access to pathology and laboratory medicine services in Tanzania.

Placement of pathology and laboratory medicine (PALM) services requires balancing efficiency (maximizing test volume) with equitable urban-rural access. We compared the association between population density (proxy for efficiency) and travel time to the closest facility (proxy for equitable access) across levels of Tanzania's public sector health system. We linked geospatial data for Tanzania from multiple sources. Data on facility locations and other geographic measures were collected from government and non-governmental databases. We classified facilities assuming increasing PALM availability by tier: (1) dispensaries, (2) health centres, (3) district hospitals and (4) regional/referral hospitals. We used the AccessMod 5 algorithm to estimate travel time to the closest facility for each tier across Tanzania with 500-m resolution. District-level average population density and travel time to the closest facility were calculated and presented using medians and interquartile ranges. Spatial correlations between these variables were estimated using the global Moran's I and bivariate Local Indicator of Spatial Autocorrelation, specifying a queen's neighbourhood matrix. Spatial analysis was restricted to 171 contiguous districts. The study included 5406 dispensaries, 675 health centres, 186 district hospitals and 37 regional/referral hospitals. District-level travel times were shortest for Tier 1 (median: [IQR]: 45.4 min [30.0-74.7]) and longest for Tier 4 facilities (160.2 min [107.3-260.0]). There was a weak spatial autocorrelation across tiers (Tier 1: -0.289, Tier 2: -0.292, Tier 3: -0.271 and Tier 4: -0.258) and few districts were classified as significant spatial outliers. Across tiers, geographic patterns of populated districts surrounded by neighbours with short travel time and sparsely populated districts surrounded by neighbours with long travel time were observed. Similar spatial correlation measures across health system levels suggest that Tanzania's health system reflects equitable urban-rural access to different PALM services. Longer travel times to hospital-based care could be ameliorated by shifting specialized diagnostics to more accessible lower tiers.

Implementation of the laboratory quality management system (ISO 15189): Experience from Bugando Medical Centre Clinical Laboratory - Mwanza, Tanzania.

BACKGROUND: Use of laboratory evidence-based patient health care in Tanzania remains a complex problem, as with many other countries in sub-Saharan Africa. As at 2010, 39 African countries, including Tanzania, had no clinical laboratories that met the minimum requirements for international laboratory standards (International Organization for Standardization [ISO] 15189). OBJECTIVE: The aim of this article is to share experience from Bugando Medical Centre laboratory's milestones in reaching ISO 15189 accreditation. METHODS: Mentors to address the laboratory management and technical requirements performed a gap analysis using the Southern African Development Community Accreditation system checklist. Several non-conformances were detected. System and technical procedures were developed, approved and communicated. Quality indicators were established to measure laboratory improvement and to identify issues which require immediate and preventive actions. RESULTS: The departments' external quality assessment performance increased after ISO 15189 implementation (e.g. Parasitology from 45% to 100%, Molecular Biology from no records to 100%, Biochemistry 50% to 95%, Tuberculosis Microscopy 60% to 100%, and Microbiology from 48.1% to 100%). There was a reduction in complaints, from eight to two per week. Rejected samples were reduced from 7.2% to 1.2%. Turn-around time was not recorded before implementation but reached 92% (1644/1786) of the defined targets, and the proportion of contamination in blood cultures decreased from 16% to 4%. CONCLUSION: Our experience suggests that the implementation of a quality management system is possible in resource-limited countries like Tanzania. Mentorship is necessary and should be done by professional laboratory mentors trained in quality management systems. Financial resources and motivated staff are key to achieving ISO 15189 accreditation.

HIV Resistance and Prevention of Mother-to-Child Transmission Regimen in HIV-Infected Infants in Northern Tanzania.

Prevention of mother-to-child transmission (PMTCT) guidelines recommend that all HIV-infected pregnant women receive antiretroviral therapy (Option B) and HIV-infected infants should initiate therapy with a protease inhibitor-based regimen; however, implementation of these guidelines has lagged in many resource-limited settings. Tanzania only recently implemented these guidelines with little country-specific data to inform whether HIV non-nucleoside reverse transcriptase inhibitor (NNRTI) resistance was present among infected infants under the Option A guidelines. This study aimed to identify primary resistance mutations in HIV-infected infants and to identify risk of nevirapine (NVP) resistance based on maternal and infant NVP exposure. Infant dried blood spots (DBSs) were sent to the zonal reference laboratory at Kilimanjaro Christian Medical Centre Clinical Laboratory and underwent DNA polymerase chain reaction testing for HIV as standard of care. Using the clinical laboratory registry, HIV-positive DBS cards, stored at ambient temperature, were identified and sent for further viral load testing, nucleotide sequencing, and analysis. Clinical information was obtained from the PMTCT clinical sites and the National PMTCT registry for information regarding maternal and infant demographics and PMTCT treatment regimen. Results demonstrated that infants exposed to NVP were more likely to have high level resistance mutations (HLRMs) to NVP than those infants not exposed to NVP (p = .002). The most common HLRMs to NVP were K103 N, Y181C, and Y188 L. HIV subtype A was most common, followed by subtype C. Approximately one-third of HIV-infected infants had documented referral to HIV care. This study demonstrated the ongoing need to scale up and strengthen points along the PMTCT continuum and supported the recommendation for all HIV-infected infants to initiate a lopinavir/ritonavir-based antiretroviral therapy regimen.

Laboratory quality improvement in Tanzania.

OBJECTIVES: The article describes the implementation and improvement in the first groups of medical laboratories in Tanzania selected to participate in the training program on Strengthening Laboratory Management Toward Accreditation (SLMTA). METHODS: As in many other African nations, the selected improvement plan consisted of formalized hands-on training (SLMTA) that teaches the tasks and skills of laboratory management and provides the tools for implementation of best laboratory practice. Implementation of the improvements learned during training was verified before and after SLMTA with the World Health Organization African Region Stepwise Laboratory Improvement Process Towards Accreditation checklist. RESULTS: During a 4-year period, the selected laboratories described in this article demonstrated improvement with a range of 2% to 203% (cohort I) and 12% to 243% (cohort II) over baseline scores. CONCLUSIONS: The article describes the progress made in Tanzania's first cohorts, the obstacles encountered, and the lessons learned during the pilot and subsequent implementations.

Progress in the prevention of mother to child transmission of HIV in three regions of Tanzania: a retrospective analysis.

BACKGROUND: Mother to child transmission (MTCT) of HIV-1 remains an important problem in sub-Saharan Africa where most new pediatric HIV-1 infections occur. Early infant diagnosis of HIV-1 using dried blood spot (DBS) PCR among exposed infants provides an opportunity to assess current MTCT rates. METHODS: We conducted a retrospective data analysis on mother-infant pairs from all PMTCT programs in three regions of northern Tanzania to determine MTCT rates from 2008-2010. Records of 3,016 mother-infant pairs were assessed to determine early transmission among HIV-exposed infants in the first 75 days of life. RESULTS: Of 2,266 evaluable infants in our cohort, 143 had a positive DBS PCR result at ≤ 75 days of life, for an overall transmission rate of 6.3%. Transmission decreased substantially over the period of study as more effective regimens became available. Transmission rates were tightly correlated to maternal regimen: 14.9% (9.5, 20.3) of infants became infected when women received no therapy; 8.8% (6.9, 10.7) and 3.6% (2.4, 4.8) became infected when women received single-dose nevirapine (sdNVP) or combination prophylaxis, respectively; the lowest MTCT rates occurred when women were on HAART, with 2.1% transmission (0.3, 3.9). Treatment regimens changed dramatically over the study period, with an increase in combination prophylaxis and a decrease in the use of sdNVP. Uptake of DBS PCR more than tripled over the period of study for the three regions surveyed. CONCLUSIONS: Our study demonstrates significant reductions in MTCT of HIV-1 in three regions of Tanzania coincident with increased use of more effective PMTCT interventions. The changes we demonstrate for the period of 2008-2010 occurred prior to major changes in WHO PMTCT guidelines.

One laboratory's progress toward accreditation in Tanzania.

INTRODUCTION: The Amana Regional Hospital Laboratory in Tanzania was selected, along with 11 other regional and district laboratories, to participate in a pilot programme for laboratory quality improvement using the Strengthening Laboratory Management Toward Accreditation (SLMTA) training programme. PROGRAMME IMPLEMENTATION: The SLMTA programme entailed hands-on learning, improvement projects between and after a three-workshop series, supervisory visits from an oversight team and an expert laboratory mentor to facilitate and coach the process. Audits were conducted at baseline, exit (approximately one year after baseline) and follow-up (seven months after exit) using the Stepwise Laboratory Quality Improvement Process Towards Accreditation (SLIPTA) checklist. Quality stars (zero to five) were awarded based on audit scores. RESULTS: With a dedicated staff and strong leadership from laboratory management, Amana Laboratory implemented processes, policies and procedures recommended as elements of best laboratory practices. The laboratory improved from zero stars (36%) at baseline to successfully achieving three stars (81%) at exit. This was the highest score achieved by the 12 laboratories in the programme (the median exit score amongst the other laboratories was 58%). Seven months after completion of the programme, the laboratory regressed to one star (62%). DISCUSSION: As the SLMTA improvement programme progressed, Amana Laboratory's positive attitude and hard work prevailed. With the assistance of a mentor and the support of the facility's management a strong foundation of good practices was established. Although not all improvements were maintained after the conclusion of the programme and the laboratory dropped to a one-star rating, the laboratory remained at a higher level than most laboratories in the programme.

Introducing a multi-site program for early diagnosis of HIV infection among HIV-exposed infants in Tanzania.

BACKGROUND: In Tanzania, less than a third of HIV infected children estimated to be in need of antiretroviral therapy (ART) are receiving it. In this setting where other infections and malnutrition mimic signs and symptoms of AIDS, early diagnosis of HIV among HIV-exposed infants without specialized virologic testing can be a complex process. We aimed to introduce an Early Infant Diagnosis (EID) pilot program using HIV DNA Polymerase Chain Reaction (PCR) testing with the intent of making EID nationally available based on lessons learned in the first 6 months of implementation. METHODS: In September 2006, a molecular biology laboratory at Bugando Medical Center was established in order to perform HIV DNA PCR testing using Dried Blood Spots (DBS). Ninety-six health workers from 4 health facilities were trained in the identification and care of HIV-exposed infants, HIV testing algorithms and collection of DBS samples. Paper-based tracking systems for monitoring the program that fed into a simple electronic database were introduced at the sites and in the laboratory. Time from birth to first HIV DNA PCR testing and to receipt of test results were assessed using Kaplan-Meier curves. RESULTS: From October 2006 to March 2007, 510 HIV-exposed infants were identified from the 4 health facilities. Of these, 441(87%) infants had an HIV DNA PCR test at a median age of 4 months (IQR 1 to 8 months) and 75(17%) were PCR positive. Parents/guardians for a total of 242(55%) HIV-exposed infants returned to receive PCR test results, including 51/75 (68%) of those PCR positive, 187/361 (52%) of the PCR negative, and 4/5 (80%) of those with indeterminate PCR results. The median time between blood draw for PCR testing and receipt of test results by the parent or guardian was 5 weeks (range <1 week to 14 weeks) among children who tested PCR positive and 10 weeks (range <1 week to 21 weeks) for those that tested PCR negative. CONCLUSIONS: The EID pilot program successfully introduced systems for identification of HIV-exposed infants. There was a high response as hundreds of HIV-exposed infants were registered and tested in a 6 month period. Challenges included the large proportion of parents not returning for PCR test results. Experience from the pilot phase has informed the national roll-out of the EID program currently underway in Tanzania.

The Tanzania experience: clinical laboratory testing harmonization and equipment standardization at different levels of a tiered health laboratory system.

The rapid scale-up of the care and treatment programs in Tanzania during the preceding 4 years has greatly increased the demand for quality laboratory services for diagnosis of HIV and monitoring patients during antiretroviral therapy. Laboratory services were not in a position to cope with this demand owing to poor infrastructure, lack of human resources, erratic and/or lack of reagent supply and commodities, and slow manual technologies. With the limited human resources in the laboratory and the need for scaling up the care and treatment program, it became necessary to install automated equipment and train personnel for the increased volume of testing and new tests across all laboratory levels. With the numerous partners procuring equipment, the possibility of a multitude of equipment platforms with attendant challenges for procurement of reagents, maintenance of equipment, and quality assurance arose. Tanzania, therefore, had to harmonize laboratory tests and standardize laboratory equipment at different levels of the laboratory network. The process of harmonization of tests and standardization of equipment included assessment of laboratories, review of guidelines, development of a national laboratory operational plan, and stakeholder advocacy. This document outlines this process.

Evaluation of simple rapid HIV assays and development of national rapid HIV test algorithms in Dar es Salaam, Tanzania.

BACKGROUND: Suitable algorithms based on a combination of two or more simple rapid HIV assays have been shown to have a diagnostic accuracy comparable to double enzyme-linked immunosorbent assay (ELISA) or double ELISA with Western Blot strategies. The aims of this study were to evaluate the performance of five simple rapid HIV assays using whole blood samples from HIV-infected patients, pregnant women, voluntary counseling and testing attendees and blood donors, and to formulate an alternative confirmatory strategy based on rapid HIV testing algorithms suitable for use in Tanzania. METHODS: Five rapid HIV assays: Determine HIV-1/2 (Inverness Medical), SD Bioline HIV 1/2 3.0 (Standard Diagnostics Inc.), First Response HIV Card 1-2.0 (PMC Medical India Pvt Ltd), HIV1/2 Stat-Pak Dipstick (Chembio Diagnostic System, Inc) and Uni-Gold HIV-1/2 (Trinity Biotech) were evaluated between June and September 2006 using 1433 whole blood samples from hospital patients, pregnant women, voluntary counseling and testing attendees and blood donors. All samples that were reactive on all or any of the five rapid assays and 10% of non-reactive samples were tested on a confirmatory Inno-Lia HIV I/II immunoblot assay (Immunogenetics). RESULTS: Three hundred and ninety samples were confirmed HIV-1 antibody positive, while 1043 were HIV negative. The sensitivity at initial testing of Determine, SD Bioline and Uni-Gold was 100% (95% CI; 99.1-100) while First Response and Stat-Pak had sensitivity of 99.5% (95% CI; 98.2-99.9) and 97.7% (95% CI; 95.7-98.9), respectively, which increased to 100% (95% CI; 99.1-100) on repeat testing. The initial specificity of the Uni-Gold assay was 100% (95% CI; 99.6-100) while specificities were 99.6% (95% CI; 99-99.9), 99.4% (95% CI; 98.8-99.7), 99.6% (95% CI; 99-99.9) and 99.8% (95% CI; 99.3-99.9) for Determine, SD Bioline, First Response and Stat-Pak assays, respectively. There was no any sample which was concordantly false positive in Uni-Gold, Determine and SD Bioline assays. CONCLUSION: An alternative confirmatory HIV testing strategy based on initial testing on either SD Bioline or Determine assays followed by testing of reactive samples on the Determine or SD Bioline gave 100% sensitivity (95% CI; 99.1-100) and 100% specificity (95% CI; 96-99.1) with Uni-Gold as tiebreaker for discordant results.

Human herpesvirus 8/Kaposi sarcoma herpesvirus cell association during evolution of Kaposi sarcoma.

Kaposi sarcoma (KS) is associated with a herpesvirus (HHV-8/KSHV), which expresses a latency-associated nuclear antigen (LANA). The histopathology of KS is characterized by angiogenesis, inflammatory cells, and the development of CD34+ tumor spindle cells (SCs). However, the cellular basis for the recruitment and dissemination of HHV-8 during the development of KS lesions is not clear. Twenty-nine KS biopsies with AIDS (AKS, n=22) and without HIV infection (endemic KS or EKS, n=7) were immunostained by a triple antibody method to characterize HHV-8-infected and noninfected (LANA+/-) CD34+ SCs, infiltrating CD3+, CD68+, CD20+, and CD45+ leukocytes as well as proliferating (Ki67+) cells. The CD34+/LANA+ SCs were more frequent in late (nodular) as compared with early (patch/plaque) KS stages. However, in late AKS 36.0% of SCs (median of 11 cases) were CD34+/LANA- compared with 20.7% in early cases (median of 11 cases). Furthermore, both AKS and EKS showed, at all stages, a small (4.1-6.5%) population of LANA+/CD34- cells. Proliferating Ki67+ cells were seen (4.5-11.5%) at all KS stages, and were usually more frequent in early AKS, but no significant difference was observed between nodular AKS and EKS. Most of the proliferating cells in the KS lesions were LANA+/CD34+ but a small fraction was LANA+/CD34-. Lesional CD68+ and CD3+ cells varied between AKS (7.3 and 5.2%, respectively) and EKS (4.9 and 3.1%, respectively) but were not clearly stage related. No LANA+ cells were CD3+, CD20+, or CD45+ and very few (<0.5%) were CD68+. These results indicate that not all CD34+ KS SCs were LANA+, suggesting recruitment of noninfected SCs to the lesions. Cell proliferation in general was much higher in early as compared with the late AKS stages. LANA+ SCs could have a proliferative advantage as suggested by higher frequency of cycling (Ki67+) LANA+ SCs. Few macrophages but no lymphocytes are LANA+.

Serum HHV8 DNA and Tat antibodies in Kaposi's sarcoma patients with and without HIV-1 infection.

Human herpesvirus 8 or Kaposi's sarcoma-associated herpesvirus (HHV8/KSHV) is believed to be the most important etiopathological factor of Kaposi's sarcoma (KS) and some specific types of malignant lymphomas. The diagnostic and prognostic significance of serum viral load in endemic (African) areas is poorly understood. In AIDS-related KS (AKS) it has been shown that HIV-Tat may be of pathogenic importance and that immunoreactivity to Tat may have prognostic significance. Here we report on the quantitative analysis of HHV8 DNA in serum from Tanzanian patients with KS (n = 19), either AIDS-related (AKS) (n = 14) or endemic KS (EKS) (n = 5) and non-KS control individuals (n = 4). Fourteen AKS sera were also tested for HIV-tat antibodies by a direct ELISA assay. In AKS patients detectable (12 out of 14) serum HHV8 DNA levels showed a median of 1400 copies/ml as compared to a median of 200 copies/ml for EKS, but for one AKS case with an exceptionally high level (25,500 copies/ml). The serum HHV8 DNA levels were usually higher in males (n = 17; median 580 DNA copies/ml) as compared to females (n = 6; median 120 DNA copies/ml) and in early, patch stages (n = 8; median 2,750 copies/ml) as compared to late, nodular stages (n = 11; median 200 DNA copies/ml). Of fourteen sera from AKS patients, seven were positive for antibody against HIV-1 tat. Epitope analysis of the anti-tat antibody spectrum showed reactivity to various non-functional sites, but not towards the functional epitopes 46-60 (TAR-binding region).

Cross-talk between human herpesvirus 8 and the transactivator protein in the pathogenesis of Kaposi's sarcoma in HIV-infected patients.

AIDS-associated Kaposi's sarcoma (AKS) is particularly aggressive and it is one of the principal neoplasms in regions of Africa affected by both high endemic HHV8 and epidemic HIV infection. In this study, serum samples from 18 patients with Kaposi's sarcoma from Tanzania, mostly males (n = 15 vs 3), were subjected to analysis with respect to HHV8-DNA load and antibody spectrum against the HIV-1 tat protein. Of the 18 patients, 14 were HIV-1-positive. The median HHV8 virus load in the HIV-1-positive group was 2075 DNA copies/ml, compared to 450 copies/ml in the HIV-1-negative group. In the HIV-1-positive group, the males had a higher HHV8-DNA virus load as compared to females (median: 4600 vs 1400 genome copies per ml). Since tat can promote AKS development (4-6) by intercellular signalling pathways, and these signals can be abolished by anti-tat IgG (7-9), we have examined the anti-tat IgG spectrum in this study. It would be expected that the levels of serum HHV8-DNA are higher in KS patients who have low anti-tat IgG titer, or who are anti-tat IgG-negative. In the present study, seven out of fifteen AKS patients were positive for anti-tat IgG. Although, we have not seen a strict quantitative relationship between serum anti-tat IgG and HHV8-DNA levels, our data appear to suggest a correlation between the two parameters. In view of these observations and the published data, we suggest that cross-signalling pathways between the tat protein and HHV8-DNA are involved in the complexity of pathogenesis of Kaposi's sarcoma.

Detection of human herpesvirus 8 DNA in serum from blood donors with HHV-8 antibodies indicates possible bloodborne virus transmission.

Human herpesvirus 8 (HHV-8) is associated with Kaposi's sarcoma. There is a high seroprevalence of HHV-8 in several African countries, but the transmission route is not known definitively. In this study 174 serum samples from blood donors in Tanzania were examined by immunofluorescence assays detecting antibodies to latent and lytic HHV-8 antigens. Real-time polymerase chain reaction was used for detection and quantification of HHV-8 DNA in serum. In all, 83/174 (48%) of the subjects had antibodies to latent or lytic antigens. Forty (23%) had antibodies to both antigens and of those eight (20%) had detectable HHV-8 DNA in serum. HHV-8 DNA load correlated with antibody titres to lytic, but not latent, HHV-8 antigens. This supports the usefulness of anti-lytic antibodies in HHV-8 serology and suggests that transmission of HHV-8 by blood contact could be of importance in this region.