Burden of sickle cell trait and disease in the Uganda Sickle Surveillance Study (US3): a cross-sectional study

Background Sickle cell disease contributes substantially to mortality in children younger than 5 years in sub-Saharan Africa. In Uganda, 20 000 babies per year are thought to be born with sickle cell disease, but accurate data are not available. We did the cross-sectional Uganda Sickle Surveillance Study to assess the burden of disease. Methods The primary objective of the study was to calculate prevalence of sickle cell trait and disease. We obtained punch samples from dried blood spots routinely collected from HIV-exposed infants in ten regions and 112 districts across Uganda for the national Early Infant Diagnosis programme. Haemoglobin electrophoresis by isoelectric focusing was done on all samples to identify those from babies with sickle trait or disease. Findings Between February, 2014, and March, 2015, 99 243 dried blood spots were analysed and results were available for 97 631. The overall number of children with sickle cell trait was 12 979 (13·3%) and with disease was 716 (0·7%). Sickle cell numbers ranged from 631 (4·6%) for trait and 23 (0·2%) for disease of 13 649 in the South Western region to 1306 (19·8%) for trait and 96 (1·5%) for disease of 6581 in the East Central region. Sickle cell trait was seen in all districts. The lowest prevalence was less than 3·0% in two districts. Eight districts had prevalence greater than 20·0%, with the highest being 23·9%. Sickle cell disease was less common in children older than 12 months or who were HIV positive, which is consistent with comorbidity and early mortality. Interpretation Prevalence of sickle cell trait and disease were high in Uganda, with notable variation between regions and districts. The data will help to inform national strategies for sickle cell disease, including neonatal screening

Building a sickle cell disease screening program in the Republic of Uganda: the Uganda Sickle Surveillance Study (US3) with 3 years of follow-up screening results.

The prevalence of sickle cell disease (SCD) in the Republic of Uganda is higher than in the United States, but there are no accurate countrywide data and no newborn screening program has been established. The Early Infant Diagnosis (EID) program is well established to analyze dried blood spots (DBSs) collected from HIV-exposed infants (ie, those born to HIV-positive mothers). HIV-positive infants are identified and placed into specialty care. At the request of the Uganda Ministry of Health, a partnership was developed between Cincinnati Children’s Hospital Medical Center, Makerere University, and the Uganda Central Public Health Laboratories (CHPL) to build local laboratory capacity for testing DBSs for sickle cell trait (SCT) and SCD. The Uganda Sickle Surveillance Study (US3) was designed to identify SCT or SCD in DBSs collected throughout the national EID program. After US3, screening commenced in high-burden districts with local capacity built to provide clinical care for affected infants

Hemoglobin variants identified in the Uganda Sickle Surveillance Study

The Uganda Sickle Surveillance Study analyzed dried blood spots that were collected from almost 100 000 infants and young children from all 10 regions and 112 districts in the Republic of Uganda, with the primary objective of determining the prevalence of sickle cell trait and disease. An overall prevalence of 13.3% sickle cell trait and 0.7% sickle cell disease was recently reported. The isoelectric focusing electrophoresis technique coincidentally revealed numerous hemoglobin (Hb) variants (defined as an electrophoresis band that was not Hb A, Hb F, Hb S, or Hb C) with an overall country-wide prevalence of 0.5%, but with considerable geographic variability, being highest in the northwest regions and districts. To elucidate these Hb variants, the original isoelectric focusing (IEF) gels were reviewed to identify and locate the variant samples; corresponding dried blood spots were retrieved for further testing. Subsequent DNA-based investigation of 5 predominant isoelectric focusing patterns identified 2 α-globin variants (Hb Stanleyville II, Asn78Lys; Hb G-Pest, Asp74Asn), 1 β-globin variant (Hb O-Arab, Glu121Lys), and 2 fusion globin variants (Hb P-Nilotic, β31-δ50; Hb Kenya, Aγ81Leu-β86Ala). Compound heterozygotes containing an Hb variant plus Hb S were also identified, including both Hb S/O-Arab and HbS/Kenya. Regional differences in the types and prevalence of these hemoglobin variants likely reflect tribal ancestries and migration patterns. Algorithms are proposed to characterize these Hb variants, which will be helpful for emerging neonatal hemoglobinopathy screening programs that are under way in sub-Saharan Africa

Hepatitis C Virus (HCV) Evades NKG2D-Dependent NK Cell Responses through NS5A-Mediated Imbalance of Inflammatory Cytokines

Understanding how hepatitis C virus (HCV) induces and circumvents the host's natural killer (NK) cell-mediated immunity is of critical importance in efforts to design effective therapeutics. We report here the decreased expression of the NKG2D activating receptor as a novel strategy adopted by HCV to evade NK-cell mediated responses. We show that chronic HCV infection is associated with expression of ligands for NKG2D, the MHC class I-related Chain (MIC) molecules, on hepatocytes. However, NKG2D expression is downmodulated on circulating NK cells, and consequently NK cell-mediated cytotoxic capacity and interferon-γ production are impaired. Using an endotoxin-free recombinant NS5A protein, we show that NS5A stimulation of monocytes through Toll-like Receptor 4 (TLR4) promotes p38- and PI3 kinase-dependent IL-10 production, while inhibiting IL-12 production. In turn, IL-10 triggers secretion of TGFβ which downmodulates NKG2D expression on NK cells, leading to their impaired effector functions. Moreover, culture supernatants of HCV JFH1 replicating Huh-7.5.1 cells reproduce the effect of recombinant NS5A on NKG2D downmodulation. Exogenous IL-15 can antagonize the TGFβ effect and restore normal NKG2D expression on NK cells. We conclude that NKG2D-dependent NK cell functions are modulated during chronic HCV infection, and demonstrate that this alteration can be prevented by exogenous IL-15, which could represent a meaningful adjuvant for therapeutic intervention

SNAPSHOT USA 2019 : a coordinated national camera trap survey of the United States

This article is protected by copyright. All rights reserved.With the accelerating pace of global change, it is imperative that we obtain rapid inventories of the status and distribution of wildlife for ecological inferences and conservation planning. To address this challenge, we launched the SNAPSHOT USA project, a collaborative survey of terrestrial wildlife populations using camera traps across the United States. For our first annual survey, we compiled data across all 50 states during a 14-week period (17 August - 24 November of 2019). We sampled wildlife at 1509 camera trap sites from 110 camera trap arrays covering 12 different ecoregions across four development zones. This effort resulted in 166,036 unique detections of 83 species of mammals and 17 species of birds. All images were processed through the Smithsonian's eMammal camera trap data repository and included an expert review phase to ensure taxonomic accuracy of data, resulting in each picture being reviewed at least twice. The results represent a timely and standardized camera trap survey of the USA. All of the 2019 survey data are made available herein. We are currently repeating surveys in fall 2020, opening up the opportunity to other institutions and cooperators to expand coverage of all the urban-wild gradients and ecophysiographic regions of the country. Future data will be available as the database is updated at eMammal.si.edu/snapshot-usa, as well as future data paper submissions. These data will be useful for local and macroecological research including the examination of community assembly, effects of environmental and anthropogenic landscape variables, effects of fragmentation and extinction debt dynamics, as well as species-specific population dynamics and conservation action plans. There are no copyright restrictions; please cite this paper when using the data for publication.Publisher PDFPeer reviewe

EPIDEMIOLOGICAL EVALUATION OF THE NATIONAL SICKLE CELL SCREENING PROGRAM IN THE REPUBLIC OF UGANDA

Sickle cell anemia contributes substantially to childhood morbidity and mortality in sub-Saharan Africa, where there are scarce health resources and inadequate awareness among healthcare providers and the community. Without early diagnosis and initiation of preventive treatments, most infants will die of acute complications before their fifth birthday. Information on the mortality associated with sickle cell anemia is excluded from global statistical summaries due to the lack of accurate data, making sickle cell anemia an invisible killer of children on the African continent. Information from long-term large-scale sickle cell screening efforts is not yet available in Africa; therefore, a mixed-methods study was conducted using five years of data from Uganda’s national sickle cell screening program and from interviews with 23 sickle cell healthcare providers. This was achieved with the following objectives: (i) characterize the epidemiology of sickle cell disease in Uganda; (ii) evaluate the centralized sickle cell screening laboratory in Uganda; and (iii) describe healthcare providers’ experiences with sickle cell screening in Uganda. ix A total of 324,356 children were screened for sickle cell trait and disease from February 2014 to March 2019. A high national burden of sickle cell disease (0.9%) was confirmed. Among samples referred specifically for sickle cell testing, the overall prevalence of sickle cell disease was 9.7% and particularly elevated in high-burden districts where focused screening occurred. A large proportion of affected children were tested between 5-9 months of age, coincident with onset of disease signs and symptoms. With the use of crude birth rate data, a high screening coverage of newborns was observed several high-burden districts. Median turnaround time from sample collection to result reporting was 16 days (IQR 11, 24). Predictors affecting prolonged turnaround time were sample volume, health facility level, and testing month. Cost per test was $4.46 and cost per case detected was$483.74. Barriers to screening were identified, including the need for initial and ongoing training for healthcare providers on sickle cell screening and management; healthcare system capacity issues, such as resources of staff and supplies, and system fragmentation; and the knowledge and awareness gap of sickle cell disease in the community. Focused sickle cell screening has been a time- and cost-effective approach to begin to confront Uganda’s large burden of disease. However, as the adverse impact of sickle cell disease on the population becomes more fully realized, a shift toward earlier and more widespread screening through healthcare provider training, community education, and improved sickle cell care models will be most advantageous. The experiences in Uganda are instructive for all countries in sub-Saharan Africa with a large sickle cell burden

Burden of sickle cell trait and disease in the Uganda Sickle Surveillance Study (US3): a cross-sectional study

Background: Sickle cell disease contributes substantially to mortality in children younger than 5 years in sub-Saharan Africa. In Uganda, 20 000 babies per year are thought to be born with sickle cell disease, but accurate data are not available. We did the cross-sectional Uganda Sickle Surveillance Study to assess the burden of disease. Methods: The primary objective of the study was to calculate prevalence of sickle cell trait and disease. We obtained punch samples from dried blood spots routinely collected from HIV-exposed infants in ten regions and 112 districts across Uganda for the national Early Infant Diagnosis programme. Haemoglobin electrophoresis by isoelectric focusing was done on all samples to identify those from babies with sickle trait or disease. Findings: Between February, 2014, and March, 2015, 99 243 dried blood spots were analysed and results were available for 97 631. The overall number of children with sickle cell trait was 12 979 (13·3%) and with disease was 716 (0·7%). Sickle cell numbers ranged from 631 (4·6%) for trait and 23 (0·2%) for disease of 13 649 in the South Western region to 1306 (19·8%) for trait and 96 (1·5%) for disease of 6581 in the East Central region. Sickle cell trait was seen in all districts. The lowest prevalence was less than 3·0% in two districts. Eight districts had prevalence greater than 20·0%, with the highest being 23·9%. Sickle cell disease was less common in children older than 12 months or who were HIV positive, which is consistent with comorbidity and early mortality. Interpretation: Prevalence of sickle cell trait and disease were high in Uganda, with notable variation between regions and districts. The data will help to inform national strategies for sickle cell disease, including neonatal screening. Funding: Cincinnati Children's Research Foundation

SNAPSHOT USA 2019:a coordinated national camera trap survey of the United States

With the accelerating pace of global change, it is imperative that we obtain rapid inventories of the status and distribution of wildlife for ecological inferences and conservation planning. To address this challenge, we launched the SNAPSHOT USA project, a collaborative survey of terrestrial wildlife populations using camera traps across the United States. For our first annual survey, we compiled data across all 50 states during a 14-week period (17 August - 24 November of 2019). We sampled wildlife at 1509 camera trap sites from 110 camera trap arrays covering 12 different ecoregions across four development zones. This effort resulted in 166,036 unique detections of 83 species of mammals and 17 species of birds. All images were processed through the Smithsonian's eMammal camera trap data repository and included an expert review phase to ensure taxonomic accuracy of data, resulting in each picture being reviewed at least twice. The results represent a timely and standardized camera trap survey of the USA. All of the 2019 survey data are made available herein. We are currently repeating surveys in fall 2020, opening up the opportunity to other institutions and cooperators to expand coverage of all the urban-wild gradients and ecophysiographic regions of the country. Future data will be available as the database is updated at eMammal.si.edu/snapshot-usa, as well as future data paper submissions. These data will be useful for local and macroecological research including the examination of community assembly, effects of environmental and anthropogenic landscape variables, effects of fragmentation and extinction debt dynamics, as well as species-specific population dynamics and conservation action plans. There are no copyright restrictions; please cite this paper when using the data for publication.</p