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Item Use of real-time multiplex PCR, malaria rapid diagnostic test and microscopy to investigate the prevalence of Plasmodium species among febrile hospital patients in Sierra Leone(BioMed Central, 2020-02-21) Łęski, Tomasz A.BACKGROUND: Malaria continues to affect over 200 million individuals every year, especially children in Africa. Rapid and sensitive detection and identification of Plasmodium parasites is crucial for treating patients and monitoring of control efforts. Compared to traditional diagnostic methods such as microscopy and rapid diagnostic tests (RDTs), DNA based methods, such as polymerase chain reaction (PCR) offer significantly higher sensitivity, definitive discrimination of Plasmodium species, and detection of mixed infections. While PCR is not currently optimized for routine diagnostics, its role in epidemiological studies is increasing as the world moves closer toward regional and eventually global malaria elimination. This study demonstrates the field use of a novel, ambient temperature-stabilized, multiplexed PCR assay in a small hospital setting in Sierra Leone. METHODS: Blood samples from 534 febrile individuals reporting to a hospital in Bo, Sierra Leone, were tested using three methods: a commercial RDT, microscopy, and a Multiplex Malaria Sample Ready (MMSR) PCR designed to detect a universal malaria marker and species-specific markers for Plasmodium falciparum and Plasmodium vivax. A separate PCR assay was used to identify species of Plasmodium in samples in which MMSR detected malaria, but was unable to identify the species. RESULTS: MMSR detected the presence of any malaria marker in 50.2% of all tested samples with P. falciparum identified in 48.7% of the samples. Plasmodium vivax was not detected. Testing of MMSR P. falciparum-negative/universal malaria-positive specimens with a panel of species-specific PCRs revealed the presence of Plasmodium malariae (n = 2) and Plasmodium ovale (n = 2). The commercial RDT detected P. falciparum in 24.6% of all samples while microscopy was able to detect malaria in 12.8% of tested specimens. CONCLUSIONS: Wider application of PCR for detection of malaria parasites may help to fill gaps existing as a result of use of microscopy and RDTs. Due to its high sensitivity and specificity, species coverage, room temperature stability and relative low complexity, the MMSR assay may be useful for detection of malaria and epidemiological studies especially in low-resource settings.Item How to prevent and address safeguarding concerns in global health research programmes: practice, process and positionality in marginalised spaces(BMJ, 2020-05-01) Aktar, BacheraSafeguarding is rapidly rising up the international development agenda, yet literature on safeguarding in related research is limited. This paper shares processes and practice relating to safeguarding within an international research consortium (the ARISE hub, known as ARISE). ARISE aims to enhance accountability and improve the health and well-being of marginalised people living and working in informal urban spaces in low-income and middle-income countries (Bangladesh, India, Kenya and Sierra Leone). Our manuscript is divided into three key sections. We start by discussing the importance of safeguarding in global health research and consider how thinking about vulnerability as a relational concept (shaped by unequal power relations and structural violence) can help locate fluid and context specific safeguarding risks within broader social systems. We then discuss the different steps undertaken in ARISE to develop a shared approach to safeguarding: sharing institutional guidelines and practice; facilitating a participatory process to agree a working definition of safeguarding and joint understandings of vulnerabilities, risks and mitigation strategies and share experiences; developing action plans for safeguarding. This is followed by reflection on our key learnings including how safeguarding, ethics and health and safety concerns overlap; the challenges of referral and support for safeguarding concerns within frequently underserved informal urban spaces; and the importance of reflective practice and critical thinking about power, judgement and positionality and the ownership of the global narrative surrounding safeguarding. We finish by situating our learning within debates on decolonising science and argue for the importance of an iterative, ongoing learning journey that is critical, reflective and inclusive of vulnerable people.Item High crossreactivity of human T cell responses between Lassa virus lineages(Public Library of Science, 2020-03-06) Sullivan, Brian MLassa virus infects hundreds of thousands of people each year across rural West Africa, resulting in a high number of cases of Lassa fever (LF), a febrile disease associated with high morbidity and significant mortality. The lack of approved treatments or interventions underscores the need for an effective vaccine. At least four viral lineages circulate in defined regions throughout West Africa with substantial interlineage nucleotide and amino acid diversity. An effective vaccine should be designed to elicit Lassa virus specific humoral and cell mediated immunity across all lineages. Most current vaccine candidates use only lineage IV antigens encoded by Lassa viruses circulating around Sierra Leone, Liberia, and Guinea but not Nigeria where lineages I-III are found. As previous infection is known to protect against disease from subsequent exposure, we sought to determine whether LF survivors from Nigeria and Sierra Leone harbor memory T cells that respond to lineage IV antigens. Our results indicate a high degree of cross-reactivity of CD8+ T cells from Nigerian LF survivors to lineage IV antigens. In addition, we identified regions within the Lassa virus glycoprotein complex and nucleoprotein that contributed to these responses while T cell epitopes were not widely conserved across our study group. These data are important for current efforts to design effective and efficient vaccine candidates that can elicit protective immunity across all Lassa virus lineages.Item Endotheliopathy and Platelet Dysfunction as Hallmarks of Fatal Lassa Fever(Centers for Disease Control and Prevention, 2020-09-29) Horton, Lucy E.L assa fever (LF) is an acute viral hemorrhagic fever endemic to West Africa, where ≈300,000-500,000 cases/year occur and mortality rates are high (1).Humans primarily are infected from exposure to excreta from the rodent host, Natal multimammate mouse (Mastomys natalensis).Pregnant women especially are susceptible to severe disease; infection during pregnancy usually leads to spontaneous abortion (2).The high rates illness and death, lack of vaccines or approved treatments, and potential to cause a public health emergency led to the US Centers for Disease Control and Prevention to classify LF as a category A bioterrorism agent (https://emergency.cdc.gov/agent/agentlist-category.asp) and the World Health Organization to classify LF as a priority disease (https://www.who.int/dg/priorities).Early clinical manifestations and symptoms of LF often are nonspecific and easily confused with other diseases prevalent in the endemic region, such as malaria and typhoid fever.Consequently, patients often are not admitted for LF treatment until symptoms are severe and they have failed other therapies.Bleeding at mucous membranes and edema generally are seen in the most severe cases (3,4), but bleeding diathesis reportedly was common during a recent outbreak in Nigeria (4).Overt hemorrhage is rare, mostly limited to the mucosal surfaces, and not severe enough to cause shock.Pathologic changes seen on autopsy lack major cell and tissue injury but include signs of pleural effusion, pulmonary edema, ascites, and gastrointestinal mucosa bleeding (5,6), all indications of systemic vascular leakage.Severely ill LF patients often have mild to moderate thrombocytopenia, but rarely have platelet counts <100,000/μL (7).Thrombocytopenia is a common feature of hemorrhagic fevers and vascular permeability disorders (8), but the decrease in platelet counts in acute LF is not low enough to cause spontaneous hemorrhage.LF could be characterized as a disease of enhanced vascular permeability but the underlying Endotheliopathy and Platelet Dysfunction as Hallmarks of Fatal Lassa FeverItem Ebola Virus Neutralizing Antibodies in Dogs from Sierra Leone, 2017(Centers for Disease Control and Prevention, 2020-03-04) Fischer, KerstinE bolaviruses (family Filoviridae) comprise highly pathogenic RNA viruses with zoonotic potential.After sporadic introduction from an animal reservoir into the human population, the main route of transmission has been from human to human, causing outbreaks of hemorrhagic fever with case-fatality rates up to 90% (1).Although molecular and serologic evidence strongly points toward certain species of bat as reservoir hosts for ebolaviruses (2,3), a bat-derived Ebola virus (EBOV) isolate has not yet been detected.Despite intensive serologic surveillance focusing on the role of bats, wildlife, and livestock in EBOV ecology (2,4-7), to our knowledge, only 2 reports describe analysis of serum from dogs in Gabon and Liberia after Ebola virus disease (EVD) outbreaks in 2001 (Gabon) and 2014-2016 (Liberia) (8,9).Although antibodies against EBOV were detected by indirect ELISA, neither EBOV antigen nor viral genome was detected in samples from Gabon.The highest seroprevalence (31.8%) was reported from villages where dogs were reportedly exposed to the virus through contact with human EVD patients or by eating infected animal carcasses (8).In Liberia, a multiplex approach indicated that 47 (73%) of 64 dogs had potentially been exposed to filoviruses (9).To further investigate the role of dogs in EBOV ecology, we collected 300 serum samples from 174 male (58%) and 126 female (42%) dogs in Moyamba District, Sierra Leone (Figure 1). The StudyWe sampled only owned and healthy dogs from communities that have been affected by the West Africa EVD outbreak (Appendix, https://wwwnc.cdc.gov/EID/article/26/4/19-0802-App1.pdf).Sampling was performed in rural and urban areas that had been affected by the historically largest EVD outbreak involving the Makona strain during 2014-2016 in West Africa.At the time of sample collection (October-December 2017), of the 300 dogs, 163 were >2 years of age (Table 1).Animals were handled according to a Njala University Institutional Review Board protocol (no.IRB00008861/FWA00018924).Initially, we screened dog serum samples for the presence of EBOV nucleoprotein (NP)-specific antibodies in an indirect ELISA, as previously described for pigs (5), with slight modifications.Using a horseradish peroxidase-labeled protein A/G-specific conjugate, we considered 36 (12%) serum samples to be reactive toward the Escherichia coli-derived EBOV-NP (Tables 1, 2).Subsequent Western blot analyses based on insect cell-derived EBOV-NP (5) confirmed the presence of EBOV-NP reactive antibodies in 20 (6.6%) samples.Furthermore, we performed virus neutralization tests (VNTs) by using transcription and replication competent virus-like particles (trVLP) and authentic EBOV (variant Mayinga) as described previously (5,10) (Appendix).We found that 12 (4%) serum samples efficiently inhibited EBOV infection with robust neutralizing titers of 1:16-1:45 and that another 6 samples had weakly positive titers of 1:11-1:13 (Tables 1, 2).Overall, titers from the trVLP-based VNTs with an established cutoff at 80% inhibition of reporter activity were comparable to those of VNTs with live virus (Figure 2). ConclusionsEBOV seroprevalence detected by ELISA in dogs from EVD-endemic areas in Gabon (25.2%-31.8%)(8) was lower than that detected in dogs in our study in Sierra Leone (12%).Technically, differences in detectable seroprevalence could be explained by different preparations used (virus-infected cell lysates in ELISA in Ebola Virus Neutralizing Antibodies in Dogs from Sierra Leone, 2017Item Building diagnostic systems in Sierra Leone: The role of point-of-care devices in laboratory strengthening(AOSIS, 2020-04-01) Ansumana, RashidThe African Journal of Laboratory Medicine focuses on the role of the laboratory and its professionals in the clinical and public healthcare sectors, and is specifically based on an African frame of reference.Item The niche of One Health approaches in Lassa fever surveillance and control(BioMed Central, 2021-04-24) Arruda, Liã BárbaraLassa fever (LF), a zoonotic illness, represents a public health burden in West African countries where the Lassa virus (LASV) circulates among rodents. Human exposure hinges significantly on LASV ecology, which is in turn shaped by various parameters such as weather seasonality and even virus and rodent-host genetics. Furthermore, human behaviour, despite playing a key role in the zoonotic nature of the disease, critically affects either the spread or control of human-to-human transmission. Previous estimations on LF burden date from the 80s and it is unclear how the population expansion and the improvement on diagnostics and surveillance methods have affected such predictions. Although recent data have contributed to the awareness of epidemics, the real impact of LF in West African communities will only be possible with the intensification of interdisciplinary efforts in research and public health approaches. This review discusses the causes and consequences of LF from a One Health perspective, and how the application of this concept can improve the surveillance and control of this disease in West Africa.Item SARS-CoV-2 antibody prevalence in Sierra Leone, March 2021: a cross-sectional, nationally representative, age-stratified serosurvey(BMJ, 2021-11-01) Barrie, Mohamed BailorBackground As of 26 March 2021, the Africa CDC had reported 4,159,055 cases of COVID-19 and 111,357 deaths among the 55 African Union Member States; however, no country has published a nationally representative serosurvey as of May 2021. Such data are vital for understanding the pandemic's progression on the continent, evaluating containment measures, and policy planning. Methods We conducted a cross-sectional, nationally representative, age-stratified serosurvey in Sierra Leone in March 2021 by randomly selecting 120 Enumeration Areas throughout the country and 10 randomly selected households in each of these. One to two persons per selected household were interviewed to collect information on socio-demographics, symptoms suggestive of COVID-19, exposure history to laboratory-confirmed COVID-19 cases, and history of COVID-19 illness. Capillary blood was collected by fingerstick, and blood samples were tested using the Hangzhou Biotest Biotech RightSign COVID-19 IgG/IgM Rapid Test Cassette. Total seroprevalence was was estimated after applying sampling weights. Findings The overall weighted seroprevalence was 2.6% (95% CI 1.9-3.4). This is 43 times higher than the reported number of cases. Rural seropositivity was 1.8% (95% CI 1.0-2.5), and urban seropositivity was 4.2% (95% CI 2.6-5.7). Interpretation Although overall seroprevalence was low compared to countries in Europe and the Americas (suggesting relatively successful containment in Sierra Leone), our findings indicate enormous underreporting of active cases. This has ramifications for the country's third wave (which started in June 2021), where the average number of daily reported cases was 87 by the end of the month: this could potentially be on the order of 3,700 actual infections, calling for stronger containment measures in a country with only 0.2% of people fully vaccinated. It may also reflect significant underreporting of incidence and mortality across the continent.Item Prevalence and socio-demographic associations of diet and physical activity risk-factors for cardiovascular disease in Bo, Sierra Leone(BioMed Central, 2021-08-10) Bockarie, TahirBACKGROUND: Little is known about modifiable dietary and physical activity risk factors for cardiovascular diseases (CVDs) in Sierra Leone. This information is critical to the development of health improvement interventions to reduce the prevalence of these diseases. This cross-sectional study investigated the prevalence and socio-demographic correlates of dietary and physical activity risk behaviours amongst adults in Bo District, Sierra Leone. METHODS: Adults aged 40+ were recruited from 10 urban and 30 rural sub-districts in Bo. We examined risk factors including: ≤150 min of moderate or vigorous-intensity physical activity (MVPA) weekly, physical inactivity for ≥3 h daily, ≤5 daily portions of fruit and vegetables, and salt consumption (during cooking, at the table, and in salty snacks). We used logistic regression to investigate the relationship between these outcomes and participants' socio-demographic characteristics. RESULTS: 1978 eligible participants (39.1% urban, 55.6% female) were included in the study. The prevalence of behavioural risk factors was 83.6% for ≤5 daily portions of fruit and vegetables; 41.4 and 91.6% for adding salt at the table or during cooking, respectively and 31.1% for eating salty snacks; 26.1% for MVPA ≤150 min weekly, and 45.6% for being physically inactive ≥3 h daily. Most MVPA was accrued at work (nearly 24 h weekly). Multivariable analysis showed that urban individuals were more likely than rural individuals to consume ≤5 daily portions of fruit and vegetables (Odds Ratio (OR) 1.09, 95% Confidence Interval (1.04-1.15)), add salt at the Table (OR 1.88 (1.82-1.94)), eat salty snacks (OR 2.00 (1.94-2.07)), and do MVPA ≤150 min weekly (OR 1.16 (1.12-1.21)). Male individuals were more likely to add salt at the Table (OR 1.23 (1.20-1.27)) or consume salty snacks (OR 1.35 (1.31-1.40)) than female individuals but were less likely to report the other behavioural risk-factors examined. Generally, people in lower wealth quintiles had lower odds of each risk factor than those in the higher wealth quintiles. CONCLUSION: Dietary risk factors for CVD are highly prevalent, particularly among urban residents, of Bo District, Sierra Leone. Our findings highlight that forthcoming policies in Sierra Leone need to consider modifiable risk factors for CVD in the context of urbanisation.Item Health and economic burden estimates of snakebite management upon health facilities in three regions of southern Burkina Faso(Public Library of Science, 2021-06-21) Ahmed, SayemBACKGROUND: Snakebite has become better recognized as a significant cause of death and disability in Sub-Saharan Africa, but the health economic consequences to victims and health infrastructures serving them remain poorly understood. This information gap is important as it provides an evidence-base guiding national and international health policy decision making on the most cost-effective interventions to better manage snakebite. Here, we assessed hospital-based data to estimate the health economic burden of snakebite in three regions of Burkina Faso (Centre-Ouest, Hauts Bassins and Sud-Ouest). METHODOLOGY: Primary data of snakebite victims admitted to regional and district health facilities (eg, number of admissions, mortality, hospital bed days occupied) was collected in three regions over 17 months in 2013/14. The health burden of snakebite was assessed using Disability-Adjusted Life Years (DALYs) calculations based upon hospitalisation, mortality and disability data from admitted patients amongst other inputs from secondary sources (eg, populations, life-expectancy and age-weighting constants). An activity-based costing approach to determine the direct cost of snake envenoming included unit costs of clinical staff wages, antivenom, supportive care and equipment extracted from context-relevant literature. FINDINGS: The 10,165 snakebite victims admitted to hospital occupied 28,164 hospital bed days over 17 months. The annual rate of hospitalisation and mortality of admitted snakebite victims was 173 and 1.39/100,000 population, respectively. The estimated annual (i) DALYs lost was 2,153 (0.52/1,000) and (ii) cost to hospitals was USD 506,413 (USD 49/hospitalisation) in these three regions of Burkina Faso. These costs appeared to be influenced by the number of patients receiving antivenom (10.90% in total) in each area (highest in Sud-Ouest) and the type of health facility. CONCLUSION: The economic burden of snake envenoming is primarily shouldered by the rural health centres closest to snakebite victims-facilities that are typically least well equipped or resourced to manage this burden. Our study highlights the need for more research in other regions/countries to demonstrate the burden of snakebite and the socioeconomic benefits of its management. This evidence can guide the most cost-effective intervention from government and development partners to meet the snakebite-management needs of rural communities and their health centres.