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BackgroundTuberculosis (TB) contact tracing is a key strategy for containing TB and provides addition to the passive case finding approach. However, this practice has not been implemented in Tanzania, where there is unacceptably high treatment gap of 62.1% between cases estimated and cases detected. Therefore calls for more aggressive case finding for TB to close this gap. We aimed to determine the magnitude and predictors of bacteriologically-confirmed pulmonary TB among household contacts of bacteriologically-confirmed pulmonary TB index cases in the city of Mwanza, Tanzania.MethodsThis study was carried out from August to December 2016 in Mwanza city at the TB outpatient clinics of Tertiary Hospital of the Bugando Medical Centre, Sekou-Toure Regional Hospital, and Nyamagana District Hospital. Bacteriologically-confirmed TB index cases diagnosed between May and July 2016 were identified from the laboratory registers book. Contacts were traced by home visits by study TB nurses, and data were collected using a standardized TB screening questionnaire. To detect the bacterioriologically-confirmed pulmonary TB, two sputum samples per household contact were collected under supervision for all household contacts following standard operating procedures. Samples were transported to the Bugando Medical Centre TB laboratory for investigation for TB using fluorescent smear microscopy, GeneXpert MTB/RIF and Löwenstein–Jensen (LJ) culture. Logistic regression was used to determine predictors of bacteriologically-confirmed pulmonary TB among household contacts.ResultsDuring the study period, 456 household contacts from 93 TB index cases were identified. Among these 456 household contacts, 13 (2.9%) were GeneXpert MTB/RIF positive, 18 (3.9%) were MTB-culture positive and four (0.9%) were AFB-smear positive. Overall, 29 (6.4%) of contacts had bacteriologically-confirmed pulmonary TB. Predictors of bacteriologically-confirmed pulmonary TB among household contacts were7being married (Odds ratio [OR], 3.3; 95% confidence interval [CI], 1.4–8.0; p = 0.012) and consuming less than three meals a day (OR, 3.7; 95% CI, 1.6–8.7; p = 0.009).ConclusionsOur data suggest that in Mwanza, Tanzania, seven in 100 contacts living in the same house with a TB patient develop bacteriologically-confirmed pulmonary TB. These results therefore underscore the need to implement routine TB contact tracing to control tuberculosis in high TB burden countries such as Tanzania.

BackgroundUse 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).ObjectiveThe aim of this article is to share experience from Bugando Medical Centre laboratory’s milestones in reaching ISO 15189 accreditation.MethodsMentors 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.ResultsThe 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%.ConclusionOur 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.

Objective To determine the regional- and district-level newborn prevalence of sickle cell trait and disease, and the prevalence of haemoglobin variants and genetic modifiers of sickle cell disease, in the nine regions of north-western United Republic of Tanzania. Methods We repurposed dried blood spot samples from children (aged 0–24 months) born to mothers living with human immunodeficiency virus (HIV), collected as part of the HIV Early Infant Diagnosis programme, for sickle cell diagnosis. We performed isoelectric focusing to determine whether samples had normal haemoglobin, sickle cell trait, sickle cell disease or a rare haemoglobin variant. We shipped samples diagnosed as disease or variant to Cincinnati Children’s Hospital in the United States of America for deoxyribonucleic-acid-based analyses to determine the prevalence of α-thalassaemia, glucose-6-phosphate dehydrogenase (G6PD) deficiency or fetal haemoglobin genetic modifiers. Findings We analysed a total of 17 200 specimens during February 2017–May 2018. We observed a prevalence of sickle cell trait and disease of 20.3% (3492/17 200) and 1.2% (210/17 200), respectively. District-level trait varied from 8.6% (5/58) to 28.1% (77/274). Among confirmed sickle cell disease specimens, we noted 42.7% (61/143) had 1-gene deletion and 14.7% (21/143) had 2-gene deletion α-thalassaemia trait. We documented G6PD A – deficiency in 19.2% (14/73) of males. Conclusion Our calculated prevalence is twice as high as previously reported and reinforces the need for enhanced sickle cell diagnostic services. Our district-level data will inform public health policy, allowing screening and disease-modifying hydroxyurea therapy to be focused on high-prevalence areas, until universal newborn screening is available.

Tanzania ranks third in Africa for the estimated number of annual births with sickle cell disease, but these estimates are based on sparse data from small studies reported over the past 50 years. A recently completed surveillance study from Uganda documented substantial variation in the prevalence of sickle cell trait and disease across the country. Tanzania lacks a national newborn screening program, and no contemporary multi-regional screening of infants has been undertaken. We designed and conducted a prospective study to determine the prevalence of sickle cell trait and disease by region and district in northwest Tanzania, where the prevalence of sickle cell is thought to be highest. The study used existing public health infrastructure while building local capacity for accurate diagnosis of sickle cell disease. Secondary objectives included characterization of hemoglobin variants and exploration of associations between sickle cell trait, sickle cell disease, malaria, and HIV. The Tanzania Sickle Surveillance Study (TS3) is a prospective cross-sectional study of HIV-exposed infants born in 9 regions across the Lake Zone of northwest Tanzania. In Tanzania, the HIV early infant diagnosis (EID) program collects dried blood spots (DBS) from all children born to HIV-infected mothers. DBS are transported to a central laboratory for prompt detection of HIV vertical transmission. In northwest Tanzania, the DBS are transported to Bugando Medical Centre, a teaching and consultancy hospital in Mwanza, where they are tested for HIV and then stored on-site, and thus available for further testing. Isoelectric focusing (IEF) equipment was donated to Bugando Medical Centre along with reagents and supplies. Two laboratory staff were trained by a board certified hematologist, and then attended a two day seminar by the IEF manufacturer. One pediatrician completed a 2-month observership at Cincinnati Children's Hospital. All DBS samples were tested by IEF using appropriate controls. Completed gels were scored independently by two Tanzanian staff members as normal, disease, trait, variant, or uninterpretable. DBS samples scored as disease or variant were repeated for confirmation and preserved for later genotyping. Regular Skype calls were convened with US-based collaborators to improve quality and interpretation. HIV test results were obtained from the local EID program. Between February 2017 and May 2018, 232 IEF gels were completed by the local staff. After children >24 months of age were excluded to obtain a more accurate newborn prevalence, the median age of children tested was 52 days (IQR 41-93 days), and a total of 17,278 unique DBS samples were scored. The quality of laboratory testing was extremely high with only 20 samples scored as uninterpretable and 54 with missing results, and the primary analysis was performed on the 17,204 remaining samples. The overall prevalence of sickle cell trait and disease in the entire cohort was 20.3% and 1.2%, respectively, with a 0.1% prevalence of hemoglobin variants. This corresponds to an allelic frequency of 0.114 for the sickle gene mutation and demonstrates perfect Hardy-Weinberg equilibrium. No HbC or other common beta-globin variants were identified. Geospatial mapping revealed some variation across regions, with sickle trait ranging from 16.6% to 22.5% and disease ranging from 0.5% to 1.5%. Analysis of individual districts with >100 samples revealed wider geographic variability, with sickle trait ranging from 15.2% to 27.8% and disease ranging from 0.0% to 4.3%. Co-morbidity between HIV and sickle cell disease was analyzed to compare it with the effect on mortality previously observed in Uganda. The prevalence of sickle cell disease was the same among HIV-infected and HIV-negative children (1.2%), suggesting no difference in mortality. The prevalence of sickle cell trait and disease among infants born in northwest Tanzania is very high, exceeding 20% trait and 1.2% disease. All regions in the Lake Zone are affected possibly due to lack of immigration to the area and similar environmental exposures. Targeted newborn screening can be started in high prevalence districts, using existing public health infrastructure with minimal start-up cost and training. Future work will evaluate the correlation between historical malaria prevalence and sickle cell prevalence, and identify hemoglobin variants. Disclosures Ware: Addmedica: Research Funding; Novartis: Membership on an entity's Board of Directors or advisory committees; Bristol Myers Squibb: Research Funding; Agios: Other: advisory board; Global Blood Therapeutics: Other: advisory board; Biomedomics: Research Funding; Nova Laboratories: Consultancy.