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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 [alpha]-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 [alpha]-thalassaemia trait. We documented G6PD [A.sup.-] 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. Objectif Determiner la prevalence de la drepanocytose et du trait drepanocytaire chez les nouveau-nes, ainsi que la prevalence de variants d'hemoglobine et de modificateurs genetiques de la drepanocytose dans les neufregions du nord-ouest de la Republique-Unie de Tanzanie. Methodes Nous avons reutilise des echantillons de gouttes de sang seche provenant d'enfants (ages de 0 a 24 mois) nes de meres atteintes du virus de l'immunodeficience humaine (VIH), preleves dans le cadre du programme de diagnostic precoce de l'infection a VIH chez le nourrisson pour detecter une eventuelle drepanocytose. Nous avons procede a une focalisation isoelectrique pour savoir si les echantillons presentaient une hemoglobine normale, un trait drepanocytaire, une drepanocytose ou un variant d'hemoglobine rare. Ensuite, nous avons envoye les echantillons identifies comme porteurs de la maladie ou d'un variant a l'hopital pour enfants de Cincinnati, aux Etats-Unis, afin d'analyser l'acide desoxyribonucleique et de mesurer la prevalence d'une [alpha]-thalassemie, d'un deficit en glucose-6-phosphate deshydrogenase (G6PD) ou de modificateurs genetiques de l'hemoglobine foetale. Resultats Nous avons etudie 17 200 specimens au total entre fevrier 2017 et mai 2018. Nous avons observe une prevalence de 20,3% (3492/17 200) pour la drepanocytose, et de 1,2% (210/17 200) pour le trait drepanocytaire. D'un district a l'autre, la presence du trait variait de 8,6% (5/58) a 28,1% (77/274). Nous avons constate que 42,7% (61/143) des specimens chez qui une drepanocytose avait ete confirmee etaient prives d'un gene, et 14,7% (21/143) de deux genes du trait [alpha]-thalassemique. Enfin, nous avons repertorie un deficit en G6PD [A.sup.-] chez 19,2% (14/73) des males. Conclusion La prevalence que nous avons calculee est deux fois superieure aux chiffres mentionnes precedemment, et souligne la necessite d'instaurer de meilleurs services de diagnostic de la drepanocytose. Nos donnees reparties par district fourniront des informations en matiere de politique de sante publique, afin que le depistage et le traitement modificateur de la maladie, a base d'hydroxyuree, se concentrent sur les zones de forte prevalence jusqu'a ce qu'un depistage universel des nouveau-nes soit disponible. Objetivo Determinar la prevalence de la enfermedad y del rasgo de las celulas falciformes en los recien nacidos a nivel regional y de distrito, y la prevalencia de las variantes de hemoglobina y de los modificadores geneticos de la drepanocitosis en las nueve regiones del noroeste de la Republica Unida de Tanzania. Metodos Se reutilizaron las muestras de las manchas de sangre seca de los ninos (de 0 a 24 meses de edad) nacidos de madres que padecian el virus de la inmunodeficiencia humana (VIH); estas muestras se obtuvieron a traves del programa de Diagnostico precoz del VIH en ninos para diagnosticar las celulas falciformes. Se aplico la tecnica del enfoque isoelectrico para determinar si las muestras tenian hemoglobina, rasgos de celulas falciformes, drepanocitosis normales o una variante de hemoglobina poco frecuente. Se enviaron muestras diagnosticadas como enfermedad o variante al Hospital Infantil de Cincinnati (Cincinnati Children's Hospital) en los Estados Unidos de America para analizarlas a base de acido desoxirribonucleico y asi determinar la prevalencia de talasemia a, de deficiencia de glucosa-6-fosfato deshidrogenasa (G6PD, por sus siglas en ingles) o de modificadores geneticos de hemoglobina fetal. Resultados Se analizaron un total de 17 200 muestras entre febrero de 2017 y mayo de 2018. Se observo una prevalencia del rasgo de las celulas falciformes y de la drepanocitosis del 20,3 % (3492/17 200) y del 1,2 % (210/17 200), respectivamente. El rasgo a nivel de distrito vario del 8,6 % (5/58) al 28,1 % (77/274). Se observo que en las muestras de drepanocitosis confirmadas, el 42,7 % (61/143) presentaba la eliminacion de un gen y el 14,7 % (21/143) la eliminacion de dos genes en el rasgo de talasemia a. Se registro una deficiencia de G6PD [A.sup.-] en el 19,2 % (14/73) de los varones. Conclusion La prevalencia que se calcula aqui es el doble de la que se notifico anteriormente y refuerza la necesidad de mejorar los servicios para el diagnostico de la drepanocitosis. Estos datos a nivel de distrito contribuiran a la politica de salud publica, ya que permitiran que los cribados y la terapia con hidroxicarbamida que modifica la enfermedad se centren en las zonas de alta prevalencia, hasta que se disponga de un cribado universal de los recien nacidos. [phrase omitted], Introduction Sickle cell disease is an inherited disorder of haemoglobin, caused by a mutation in the [beta]-globin subunit of adult haemoglobin. In classic autosomal recessive fashion, inheritance of one abnormal [...]

Introduction: Stroke is a severe complication of sickle cell anemia (SCA), with devastating sequelae. Transcranial Doppler (TCD) ultrasonography predicts stroke risk, but implementing TCD screening with suitable treatment for primary stroke prevention in low-resource environments remains challenging. SPHERE (NCT03948867) is a prospective phase 2 open-label hydroxyurea trial for SCA in Tanzania. Methods: After formal training and certification, local personnel screened children 2–16 years old; those with conditional (170–199 cm/s) or abnormal (≥200 cm/s) time-averaged mean velocities (TAMVs) received hydroxyurea at 20 mg/kg/day with dose escalation to maximum tolerated dose (MTD). The primary study endpoint is change in TAMV after 12 months of hydroxyurea; secondary endpoints include SCA-related clinical events, splenic volume and function, renal function, infections, hydroxyurea pharmacokinetics, and genetic modifiers. Results: Between April 2019 and April 2020, 202 children (average 6.8 ± 3.5 years, 53% female) enrolled and underwent TCD screening; 196 were deemed eligible by DNA testing. Most had numerous previous hospitalizations and transfusions, with low baseline hemoglobin (7.7 ± 1.1 g/dL) and %HbF (9.3 ± 5.4%). Palpable splenomegaly was present at enrollment in 49 (25%); average sonographic splenic volume was 103 mL (range 8–1,045 mL). TCD screening identified 22% conditional and 2% abnormal velocities, with hydroxyurea treatment initiated in 96% (45/47) eligible children. Conclusion: SPHERE has built local capacity with high-quality research infrastructure and TCD screening for SCA in Tanzania. Fully enrolled participants have a high prevalence of elevated baseline TCD velocities and splenomegaly. SPHERE will prospectively determine the benefits of hydroxyurea at MTD for primary stroke prevention, anticipating expanded access to hydroxyurea treatment across Tanzania. [ABSTRACT FROM AUTHOR]

In an effort to explore new knowledge and to develop meaningful collaborations for improving child health, the First Pan African Workshop on Newborn Screening was convened in June 2019 in Rabat, Morocco. Participants included an informal network of newborn screening stakeholders from across Africa and global experts in newborn screening and sickle cell disease. Over 150 attendees, representing 20 countries, were present including 11 African countries. The agenda focused on newborn screening rationale, techniques, system development, implementation barriers, ongoing research, and collaborations both globally and across Africa. We provide an overview of the workshop and a description of the newborn screening activities in the 11 African countries represented at the workshop, with a focus on sickle cell disease. [ABSTRACT FROM AUTHOR]

Parvovirus B19 (B19) can cause transient aplastic crisis and lead to acute severe anemia. This study investigated the relationship between B19 and anemia among children <5 years old in the city of Mwanza, Tanzania. An enzyme immunoassay was used to detect B19 IgM- and IgG-specific antibodies among children with various categories of anemia according to the World Health Organization (WHO) guidelines. A total of 265 children with median age of 28.5 months (interquartile range 18-39.5) were investigated. Eighty-six children (32.5%) had severe anemia. B19-specific IgM and IgG antibodies were detected in 24 (9%) and 46 (17.4%) children, respectively. Low hemoglobin (Hb) level (p = 0.031), Plasmodium falciparum infection (p = 0.001) and residing in rural areas (p = 0.025) independently predicted B19 IgM seropositivity. Acute B19 infection decreased Hb level by 1.1 g/dl (p = 0.003). In malaria endemic areas, acute B19 infections should be considered among children with severe anemia from rural areas. [ABSTRACT FROM AUTHOR]

Both anemia and sickle cell disease (SCD) are highly prevalent across sub-Saharan Africa, and limited resources exist to diagnose these conditions quickly and accurately. The development of simple, inexpensive, and accurate point-of-care (POC) assays represents an important advance for global hematology, one that could facilitate timely and life-saving medical interventions. In this prospective study, Robust Assays for Point-of-care Identification of Disease (RAPID), we simultaneously evaluated a POC immunoassay (Sickle SCAN™) to diagnose SCD and a first-generation POC color-based assay to detect anemia. Performed at Bugando Medical Center in Mwanza, Tanzania, RAPID tested 752 participants (age 1 day to 20 years) in four busy clinical locations. With minimally trained medical staff, the SCD POC assay diagnosed SCD with 98.1% sensitivity and 91.1% specificity. The hemoglobin POC assay had 83.2% sensitivity and 74.5% specificity for detection of severe anemia (Hb ≤ 7 g/dL). Interobserver agreement was excellent for both POC assays (r = 0.95-0.96). Results for the hemoglobin POC assay have informed the second-generation assay design to be more suitable for low-resource settings. RAPID provides practical feasibility data regarding two novel POC assays for the diagnosis of anemia and SCD in real-world field evaluations and documents the utility and potential impact of these POC assays for sub-Saharan Africa. [ABSTRACT FROM AUTHOR]

To improve control measures against malaria, Tanzania has increased the distribution of free and subsidized insecticide-treated mosquito nets (ITNs) to pregnant women. However, data on ownership and use of ITNs, as well as knowledge, attitudes and practices of these women regarding malaria are scarce. The objective of this study was to describe knowledge, attitudes and practices towards malaria, frequency of bed net use and level of ownership of bed nets among women seeking antenatal care in Iringa regional hospital, southern Tanzania. This cross-sectional study involved women attending antenatal clinic at Iringa Regional Hospital in south-western Tanzania. A pre-tested structured questionnaire was applied. Among the 222 pregnant women included, 173 (78%, 95%CI, 72-84.2) owned a bed net, and 150 (68%, 95%CI, 61-75) reported to sleep always under a bed net. The use of bed nets was mentioned by 142 (64%, 95%CI, 56.2-72). Of the 46 women who did not own a bed net, seven (15.2%) reported cost as the main obstacle for owning one. About 53% (95%CI, 44-62) preferred to use mosquito nets they bought rather than the one provided for free. Several factors such as gravidity, fearing of getting malaria, knowledge on the cause, marital status, and ways used to prevent malaria were significantly associated with mosquito net ownership (all P<0.001). Education level and gravidity were associated with the behaviour to sleep always under bed nets (P<0.002). Multigravidae (2-4 pregnancies) (OR 2.1, 95%CI 1.2-4.8) and married women (OR, 1.9, 95%CI, 1.2-5.2) were more likely to own a net, as compared to primigravidae and single women. In conclusion, ITNs ownership and use among pregnant women was good and they preferred to use the nets they bought from private sector. Thus, integrating public and private sector will improve the distribution and coverage of insecticides treated mosquito among high risk groups, such as pregnant women. [ABSTRACT FROM AUTHOR]

Plasmodium falciparum malaria and intestinal helminth infections are among the most common infections in the tropics and they share the same spatial distribution. The objective of this study was to explore the association between infections with intestinal helminths and P. falciparum infection as single helminth infections or co-infections among school children. A cross-sectional study was conducted among 400 school children in Nyamtongo, Sengerema District in Tanzania. The study involved examination of single stool and finger prick blood samples for intestinal helminths and malaria parasites. A Kato-Katz technique was employed to screen for intestinal helminths and Giemsa stained thin and thick blood smears were used to screen for malaria parasites. The results of logistic regression model adjusted for age and sex indicated no association between P. falciparum and S. mansoni (OR= 0.749, 95%CI 0.418-1.344), P. falciparum and hookworm (OR= 0.885, 95%CI 0.489-1.605) and P. falciparum and co-infection of S. mansoni and hookworm (OR=0.859, 95%CI 0.422-1.745). Using multinomial regression model adjusted for age and sex, no association was observed between P. falciparum with Schistosoma mansoni [Ratio of Relative Risk (RRR) = 0.651, 95% Confidence Interval (CI) 0.331-1.363] and hookworm (RRR=0712, CI 0.280-1.765). Similarly, no association was observed between co-infections of S. mansoni + hookworm (RRR=0.635, CI 0.268-1.504) with P. falciparum infection. Coinfections of S. mansoni, hookworm and P. falciparum among school children is common in the Nyamatongo ward, Sengerema District. We recommend prospective longitudinal studies to elucidate the interactions of malaria and helminths and its health impact in risk groups.