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Item Whole-genome sequencing and phylogenetic analysis of the first and second confirmed cases of human infection with Monkeypox virus from Sierra Leone(Elsevier BV, 2025-08-12) Yu, ShuoWhole-genome sequencing and phylogenetic analysis of the first and second confirmed cases of human infection with Monkeypox virus from Sierra LeoneTo the Editor, We read with great interest the letter by Yadav and colleagues, which detailed the need to focus on understanding the evolutionary trajectory of monkeypox virus. 1 The monkeypox virus (MPXV) is genetically classified into four primary clades (Ia, Ib, IIa, IIb).Notably, the newly identified clade Ib has emerged as the dominant strain in the current Public Health Emergency of International Concern (PHEIC), exemplified by the ongoing outbreak in the Democratic Republic of the Congo. 2 Concurrently, global transmission of clade IIb MPXV persists, underscoring that the ongoing epidemic warrants serious attention.On January 10-11, 2025, Sierra Leone released the case reports of its first two human infections with monkeypox virus during the PHEIC, becoming the final member of the Mano River Alliance to document such cases.Here, we present the two case studies with viral sequencing insights, shedding light on MPXV evolution in West Africa.Case 1 was a male in his twenties working as a car dealer who presented to the hospital in early January.He had traveled to Lungi (Port Loko District) from 26 December 2024 to 5 January 2025 (Fig. 1A).Symptom onset occurred on 6 January.Case 2, a male staff at a restaurant over 20 years old, developed symptoms on 6 January and sought hospital care in January.Both of the vesicle samples were confirmed MPXV-positive by real-time PCR using Monkeypox Virus Nucleic Acid Detection Kit at the Molecular Laboratory of 34th Military Hospital in Sierra Leone on January 10 and 11, respectively (Fig. 1A; Fig. S1 in the Appendix).Mean cycle threshold values were 20.29 for Case 1 and 15.14 for Case 2. The patients were admitted to the infectious disease isolation unit and were managed appropriately.Pre-rash symptoms included fever and headache, with rash involvement of the face, palms, and other cutaneous sites (Fig. S2 in the Appendix).Case 2 additionally presented with genital rashes with dysuria.Both patients denied animal/known case exposure, blood transfusions, travel (except for Case 1's documented trip, Journal of Infection 91 (2025) 106587Item 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 Prevalence and access to care for cardiovascular risk factors in older people in Sierra Leone: a cross-sectional survey(BMJ, 2020-09-01) Odland, Maria LisaINTRODUCTION: Prevalence of cardiovascular disease risk factors (CVDRFs) is increasing, especially in low-income countries. In Sierra Leone, there is limited empirical data on the prevalence of CVDRFs, and there are no previous studies on the access to care for these conditions. METHODS: This study in rural and urban Sierra Leone collected demographic, anthropometric measurements and clinical data from randomly sampled individuals over 40 years old using a household survey. We describe the prevalence of the following risk factors: diabetes, hypertension, dyslipidaemia, overweight or obesity, smoking and having at least one of these risk factors. Cascades of care were constructed for diabetes and hypertension using % of the population with the disease who had previously been tested ('screened'), knew of their condition ('diagnosed'), were on treatment ('treated') or were controlled to target ('controlled'). Multivariable regression was used to test associations between prevalence of CVDRFs and progress through the cascade for hypertension with demographic and socioeconomic variables. In those with recognised disease who did not seek care, reasons for not accessing care were recorded. RESULTS: Of 2071 people, 49.6% (95% CI 49.3% to 50.0%) of the population had hypertension, 3.5% (3.4% to 3.6%) had diabetes, 6.7% (6.5% to 7.0%) had dyslipidaemia, 25.6% (25.4% to 25.9%) smoked and 26.5% (26.3% to 26.8%) were overweight/obese; a total of 77.1% (76.6% to 77.5%) had at least one CVDRF. People in urban areas were more likely to have diabetes and be overweight than those living in rural areas. Moreover, being female, more educated or wealthier increased the risk of having all CVDRFs except for smoking. There is a substantial loss of patients at each step of the care cascade for both diabetes and hypertension, with less than 10% of the total population with the conditions being screened, diagnosed, treated and controlled. The most common reasons for not seeking care were lack of knowledge and cost. CONCLUSIONS: In Sierra Leone, CVDRFs are prevalent and access to care is low. Health system strengthening with a focus on increased access to quality care for CVDRFs is urgently needed.Item Knowledge and understanding of cardiovascular disease risk factors in Sierra Leone: a qualitative study of patients’ and community leaders’ perceptions(BMJ, 2020-12-01) Ignatowicz, AgnieszkaOBJECTIVES: Prevalence of cardiovascular disease risk factors (CVDRF) is increasing, especially in low-income countries. In Sierra Leone, there are no previous studies on the knowledge and the awareness of these conditions in the community. This study aimed to explore the knowledge and understanding of CVDRF, as well as the perceptions of the barriers and facilitators to accessing care for these conditions, among patients and community leaders in Sierra Leone. DESIGN: Qualitative study employing semistructured interviews and focus group discussions. SETTING: Urban and rural Bo District, Sierra Leone. PARTICIPANTS: Interviews with a purposive sample of 37 patients and two focus groups with six to nine community leaders. RESULTS: While participants possessed general knowledge of their conditions, the level and complexity of this knowledge varied widely. There were clear gaps in knowledge regarding the coexistence of CVDRF and their consequences, as well as the link between behavioural factors and CVDRF. An overarching theme from the data was the need to create an understanding and awareness of CVDRF in the community in order to prevent and improve management of these conditions. Cost was also seen as a major barrier to accessing care for CVDRFs. CONCLUSIONS: The knowledge gaps identified in this study highlight the need to design strategies and interventions that improve knowledge and recognition of CVDRF in the community. Interventions should specifically consider how to develop and enhance awareness about CVDRF and their consequences. They should also consider how patients seek help and where they access it.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 Effects of disruption from COVID-19 on antimalarial strategies(Nature Portfolio, 2020-08-17) Ansumana, RashidItem 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 Ebola and COVID-19 in Sierra Leone: comparative lessons of epidemics for society(Cambridge University Press, 2020-11-01) Richards, PaulThis case study focuses on two epidemic diseases in Sierra Leone. Ebola in 2014–15 drew international response, but was contained within the Upper West African region. COVID-19 reached Sierra Leone in April 2020 as part of a global pandemic. Local social knowledge has been an important factor in shaping responses to both diseases. In the case of Ebola, infection was concentrated in families, and responders needed a good knowledge of family interactional dynamics. COVID-19 is a more public disease. Responders have to assess risk factors in workplaces, markets, and places of worship. Comparing and contrasting the two cases also draws attention to different aspects of the historical context. Ebola response indexes Sierra Leone’s history as a humanitarian project associated with the abolition of the slave trade. The pandemic challenge of COVID-19 draws attention to Sierra Leone’s nodal position within a global diaspora rooted in Atlantic slavery and emancipation. Responders are forced to consider the ways in which the two infections articulate different aspects of calls for global social justice.