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BackgroundSickle cell disease (SCD) is a recognized cause of childhood mortality. Tanzania has the fifth highest incidence of SCD (with an estimated 11 000 SCD annual births) worldwide. Although newborn screening (NBS) for SCD and comprehensive healthcare have been shown to reduce under-5 mortality by up to 94% in high-income countries such as the USA, no country in Africa has maintained NBS for SCD as a national health program. The aims of this program were to establish and evaluate NBS-SCD as a health intervention in Tanzania and to determine the birth prevalence of SCD.MethodsMuhimbili University of Health and Allied Sciences conducted NBS for SCD from January 2015 to November 2016. Dried blood spot samples were collected and tested for SCD using isoelectric focusing.ResultsScreening was conducted on 3981 newborns. Thirty-one (0.8%) babies had SCD, 505 (12.6%) had sickle cell trait and 26 (0.7%) had other hemoglobinopathies. Twenty-eight (90.3%) of the 31 newborns with SCD were enrolled for comprehensive healthcare.ConclusionsThis is the first report on NBS as a health program for SCD in Tanzania. The SCD birth prevalence of 8 per 1000 births is of public health significance. It is therefore important to conduct NBS for SCD with enrollment into a comprehensive care program.

Bacteraemia is a leading cause of morbidity in sickle cell anaemia (SCA), but information from studies in Africa is limited. We evaluated 890 admissions from 648 SCA patients at a tertiary hospital in Tanzania. Bacteraemia was present in 43 admissions (4·8%); isolates included Staphylococcus aureus (12/43; 28%), non-Typhi Salmonella (9/43; 21%), Streptococcus pneumoniae (3/43; 7%) and Salmonella Typhi (2/43; 5%). Compared to SCA patients without bacteraemia, SCA patients with bacteraemia had significantly lower haemoglobin [71 g/l vs. 62 g/l, odds ratio 0·72 (95% confidence interval 0·56-0·91), P < 0·01]. Further exploration is needed of the relationship between anaemia and bacterial infections in SCA in Africa.

BACKGROUND: Haemoglobin variants, Sickle (HbS) and foetal (HbF) have been associated with malaria protection. This study explores epistatic interactions between HbS and HbF on malaria infection. METHODS: The study was conducted between March 2004 and December 2013 within the sickle cell disease (SCD) programme at Muhimbili National Hospital, Tanzania. SCD status was categorized into HbAA, HbAS and HbSS using hemoglobin electrophoresis and High Performance Liquid Chromatography (HPLC). HbF levels were determined by HPLC. Malaria was diagnosed using rapid diagnostic test and/or blood film. Logistic regression and generalized estimating equations models were used to evaluate associations between SCD status, HbF and malaria. FINDINGS: 2,049 individuals with age range 0-70 years, HbAA 311(15.2%), HbAS 241(11.8%) and HbSS 1,497(73.1%) were analysed. At enrolment, malaria prevalence was significantly higher in HbAA 13.2% compared to HbAS 1.24% and HbSS 1.34% (p

Background:The World Health Organization has declared Sickle Cell Anemia (SCA) a public health priority. There are 300,000 births/year, over 75% in Africa, with estimates suggesting that 6 million Africans will be living with SCA if average survival reaches half the African norm. Countries such as United States of America and United Kingdom have reduced SCA mortality from 3 to 0.13 per 100 person years of observation (PYO), with interventions such as newborn screening, prevention of infections and comprehensive care, but implementation of interventions in African countries has been hindered by lack of locally appropriate information. The objective of this study was to determine the incidence and factors associated with death from SCA in Dar-es-Salaam.Methods and Findings:A hospital-based cohort study was conducted, with prospective surveillance of 1,725 SCA patients recruited from 2004 to 2009, with 209 (12%) lost to follow up, while 86 died. The mortality rate was 1.9 (95%CI 1.5, 2.9) per 100 PYO, highest under 5-years old [7.3 (4.8-11.0)], adjusting for dates of birth and study enrollment. Independent risk factors, at enrollment to the cohort, predicting death were low hemoglobin (

Approximately 280 000 children are born with sickle cell anemia (SCA) in Africa annually, yet few survive beyond childhood. Falciparum malaria is considered a significant cause of this mortality. We conducted a 5-year prospective surveillance study for malaria parasitemia, clinical malaria, and severe malarial anemia (SMA) in Dar-es-Salaam, Tanzania, between 2004 and 2009. We recorded 10 491 visits to the outpatient clinic among 1808 patients with SCA and 773 visits among 679 patients without SCA. Similarly, we recorded 691 hospital admissions among 497 patients with SCA and 2017 in patients without SCA. Overall, the prevalence of parasitemia was lower in patients with SCA than in patients without SCA both at clinic (0.7% vs 1.6%; OR, 0.53; 95% CI, 0.32-0.86; P = .008) and during hospitalization (3.0% vs 5.6%; OR, 0.46; 95% CI, 0.25-0.94; P = .01). Furthermore, patients with SCA had higher rates of malaria during hospitalization than at clinic, the ORs being 4.29 (95% CI, 2.63-7.01; P < .001) for parasitemia, 17.66 (95% CI, 5.92-52.71; P < .001) for clinical malaria, and 21.11 (95% CI, 8.46-52.67; P < .001) for SMA. Although malaria was rare among patients with SCA, parasitemia during hospitalization was associated with both severe anemia and death. Effective treatment for malaria during severe illness episodes and further studies to determine the role chemoprophylaxis are required.

Background: The recognition of Sickle cell anaemia (SCA) as a problem of public health significance by the world health organisation in May 2006 has major implications in Africa where an estimated 300,000 children are born every year. In Tanzania, 20% of the population are heterozygous for the S Gene; up to 10,000 children are born every year with SCA. In order to target limited resources, research and interventional programmes require the identification of problem areas that will need to have maximum impact. Despite the protection against malaria in heterozygous individuals, paradoxically malaria is thought to be a common cause of morbidity and mortality in SCA. Bacterial infections have been implicated as a common cause of mortality and Transcranial Doppler ultrasonography (TCD) has been used to identify patients at increased risk of stroke, a recognised cause of morbidity. Aims: The study attempts to define causes of morbidity and mortality in SCA in Tanzania focusing on three major areas where it is important to establish clear answers. The aims of the study are to determine the role of malaria infection in SCA patients, to describe the major bacterial pathogens associated with admission in SCA patients and to describe the spectrum of cerebral blood flow velocities (CBFv) using TCD in SCA patients in East Africa. Study design: This is a prospective, descriptive cohort study in Muhimbili national hospital, Dar-es-salaam, Tanzania with clinical surveillance of patients in outpatient clinic every three months and during admission to hospital for any acute clinical event. Results: From March 2004 to June 2006, there have been 5,601 visits during which clinical and laboratory data has been collected on 1,000 (male 51.4%) SCA patients. The mean age of the patients is 10 7.4 years, (range 7 months54 yrs), with 91.7% below 20 years of age; 8.28% under the age of 5 years. The frequency of major clinical events, including fits (5.2%), stroke (1.9%) is reported. The prevalence of malaria parasitaemia in outpatients and during admission was 2.9% and 7.7% respectively which was lower than in the non-sickle population. There have been 516 admissions during this period, presenting with pain (44%), anaemia (17%) and fever (15%). Salmonella species (Non typhoid salmonella) was the commonest bacterial pathogens isolated. TCD was done in 400 patients (age 2 – 16 years); with 25% having a time averaged maximal mean velocity of 150 cms/second or more, suggesting stenosis. Conclusion: Preliminary analysis suggest over 90% of the SCA population are under 20 years of age, with a deficit in the under 5 year age group. There is reduced malaria infection, suggesting resistance to malaria and not susceptibility as previously reported. Painful crises were the commonest cause of admission with salmonella the most frequent pathogen isolated. TCD identified at least 25% of patients with CBFv suggestive of stenosis. This study is the initial step in describing the causes of morbidity in patients with SCD disease in Tanzania and will form the basis of longitudinal studies that will attempt to guide interventional strategies, target research and provide insight into natural history of SCD in East Africa.

Background: Significant advances have been made in the management of patients with sickle cell disease (SCD), with resultant increase in survival, most notably in the USA where 1,000 children are born with SCD every year. In contrast, in Africa, where it is estimated that 450,000 children are born with SCD every year, there has been little change in the management and minimal reduction in mortality. There is no reason to doubt that similar interventions and consequent improvements in survival can be achieved in Africa. However, the lack of resources mean that it is vital that proposed interventions are based on a clear definition of the problem. Aims: The study attempts to define causes of morbidity and mortality in SCD in Tanzania focusing on three major areas where it is important to establish clear answers. The aims of the study are to determine the role of Plasmodium falciparum infection in precipitating crises in SCD patients, to describe the major bacterial pathogens associated with admission in SCD patients and to establish the association of increased cerebral blood flow velocities (CBFv) and cerebrovascular accidents (CVA) in SCD patients in East Africa. Study design: This is an ongoing hospital based, prospective, descriptive cohort study in Muhimbili national hospital, Dar-es-salaam, Tanzania. Patients are seen in outpatient clinic every three months, if there is any acute event requiring hospital attendance and when admitted to the hospital. Results: From march 2004, there have been 3,650 visits during which clinical and laboratory data has been collected on 885 (male 51.4%) patients, all homozygous for HbS on cellulose acetate electrophoresis. The mean age of the patients is 10 ± 7.2 years, (range 9 months-54 yrs), with 22.7% being under the age of 5 years and 8.28% above 20 years. The frequency of major clinical events, including fits (5.2%), stroke (1.9%) is reported. The prevalence of malaria parasitaemia in outpatients and during admission was 2.9% and 7.7% respectively. 227 patients have been admitted during this period, presenting with pain (44%), anemia (17%) and fever (15%). Transcranial Doppler ultrasonography was done in 400 patients; with 25% having a time averaged maximal mean velocity of 150 cms/second or more, suggesting stenosis. Conclusion: This study is the initial step in describing the causes of morbidity in patients with SCD disease in Tanzania, and will form the basis of longitudinal studies that will attempt to guide interventional strategies, target research and provide insight into natural history of SCD in East Africa.