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A community action network-based intervention for improving knowledge of zoonoses among wildlife hunters and traders in Epe, Lagos, Nigeria
(Public Library of Science, 2024-11-05) Cadmus, Eniola O
The West Africa One Health project is a multi-country project designed to utilise the One Health approach and deploy the Community Action Networks (CAN), a concept rooted in the principles of community-based participatory research, to improve knowledge of high-risk communities on zoonoses. The majority of emerging zoonoses occur at the human-wildlife interface, of which wildlife hunters and traders are critical stakeholders. We assessed the effectiveness of a CAN-based intervention involving the use of a video documentary and case studies as model tools in improving the knowledge of zoonoses among wildlife hunters and traders in Epe, an established hunting community in Lagos State, Nigeria. A single-group pre-post design involving a total of 39 consenting registered wildlife stakeholders was adopted. A pre-tested, semi-structured, interviewer-administered questionnaire was used to obtain data on the participant's sociodemographic characteristics, awareness level, and knowledge of zoonoses pre and post CAN-based intervention. Data were analysed using descriptive statistics McNemar and Wilcoxon Signed Ranks tests at a 5% level of significance. The mean age of the participants was 46.7 ± 10.9 years. Most (76.9%) identified as male and had at least secondary education (89.7%). The number of participants who were aware that diseases could be contracted from animals and that it could be through inhalation and close contact increased significantly from 13 (33.3%), 2 (5.1%), and 9 (23.1%) pre-intervention to 37 (94.9%), 11 (28.2%), and 21 (53.8%) post-intervention, respectively. The overall median knowledge score increased significantly from 1 (Interquartile range (IQR): 0-2) pre-intervention to 3 (IQR: 2-4) post-intervention. The CAN-based intervention involving the use of a video documentary and case studies as model tools was effective in improving the knowledge of zoonoses among wildlife hunters and traders in the hunting community and may be beneficial for future practice.
A meta-analysis of clinical studies conducted during the West Africa Ebola virus disease outbreak confirms the need for randomized control groups
(American Association for the Advancement of Science, 2019-11-27) Dodd, Lori E.
Recent Ebola virus disease outbreaks affirm the dire need for treatments with proven efficacy. Randomized controlled clinical trials remain the gold standard but, during disease outbreaks, may be difficult to conduct due to ethical concerns and challenging field conditions. In the absence of a randomized control group, statistical modeling to create a control group could be a possibility. Such a model-based reference control would only be credible if it had the same mortality risk as that of the experimental group in the absence of treatment. One way to test this counterfactual assumption is to evaluate whether reasonable similarity exists across nonrandomized control groups from different clinical studies, which might suggest that a future control group would be similarly homogeneous. We evaluated similarity across six clinical studies conducted during the 2013-2016 West Africa outbreak of Ebola virus disease. These studies evaluated favipiravir, the biologic ZMapp, the antimalarial drug amodiaquine, or administration of convalescent plasma or convalescent whole blood. We compared the nonrandomized control groups of these six studies comprising 1147 individuals infected with Ebola virus. We found considerable heterogeneity, which did not disappear after statistical modeling to adjust for prognostic variables. Mortality risk varied widely (31 to 66%) across the nonrandomized control arms of these six studies. Models adjusting for baseline covariates (age, sex, and cycle threshold, a proxy for viral load) failed to sufficiently recalibrate these studies and showed that heterogeneity remained. Our findings highlight concerns about making invalid conclusions when comparing nonrandomized control groups to cohorts receiving experimental treatments.
A mixed-methods investigation to understand and improve the scaled-up infection prevention and control in primary care health facilities during the Ebola virus disease epidemic in Sierra Leone
(BioMed Central, 2021-08-31) Ho, Lara Shiu-Yi
BACKGROUND: The 2014-2015 Ebola epidemic in West Africa became a humanitarian crisis that exposed significant gaps in infection prevention and control (IPC) capacity in primary care facilities in Sierra Leone. Operational partners recognized the national gap and rapidly scaled-up an IPC training and infrastructure package. This prompted us to carry out a mixed-methods research study which aimed to evaluate adherence to IPC practices and understand how to improve IPC at the primary care level, where most cases of Ebola were initially presenting. The study was carried out during the national peak of the epidemic. DISCUSSION: We successfully carried out a rapid response research study that produced several expected and unexpected findings that were used to guide IPC measures during the epidemic. Although many research challenges were similar to those found when conducting research in low-resource settings, the presence of Ebola added risks to safety and security of data collectors, as well as a need to balance research activities with the imperative of response to a humanitarian crisis. A participatory approach that attempted to unify levels of the response from community upwards helped overcome the risk of lack of trust in an environment where Ebola had damaged relations between communities and the health system. CONCLUSION: In the context of a national epidemic, research needs to be focused, appropriately resourced, and responsive to needs. The partnership between local academics and a humanitarian organization helped facilitate access to study sites and approvals that allowed the research to be carried out quickly and safely, and for findings to be shared in response forums with the best chance of being taken up in real-time.
Adult malaria mortality during 2019 at Bo Government Hospital, Sierra Leone
(Bill & Melinda Gates Foundation, 2023-03-15) Kpagoi, Satta Sylvia T K
It is uncertain whether malaria is an important cause of death among adults in endemic areas. We performed a chart review of adults admitted to Bo Government Hospital during 2019. Of 893 admissions, 149 (59% female, mean age 58.5 years) had a laboratory diagnosis of malaria and 22 (14.8%) died. Mortality was significantly higher among patients with severe malaria compared with those who had non-severe malaria (6/20 \[30%\] versus 16/129 \[12.4%\], p =0.031). Our results suggest that malaria is a common cause of death in hospitalized Sierra Leonian adults.
Alcohol use among in-school adolescents in Sierra Leone
(BMJ, 2024-04-01) Osborne, Augustus
OBJECTIVE: To examine the prevalence of alcohol use and its associated factors among in-school adolescents in Sierra Leone. DESIGN: Data for the study was sourced from the 2017 Sierra Leone Global School-Based Student Health Survey, a nationally representative survey conducted among in-school adolescents aged 10-19 years using a multistage sampling methodology. Percentages were used to present the prevalence of alcohol use among in-school adolescents. Multivariable binary logistic regression analysis was performed to examine the factors associated with alcohol use among in-school adolescents. The results were presented using adjusted odds ratios (aOR) with their respective 95% confidence interval (CI). SETTING: Sierra Leone. PARTICIPANTS: A weighted sample of 1730 in-school adolescents in Sierra Leone. OUTCOME MEASURE: Current alcohol use. RESULTS: The prevalence of alcohol use among in-school adolescents was 10.7% (7.3, 15.3). In-school adolescents in senior secondary schools were more likely to use alcohol compared with those in junior secondary school (aOR=2.13; 95% CI 1.37, 3.30). The odds of alcohol use was higher among in-school adolescents who were truant at school relative to those who were not (aOR=2.24; 95% CI 1.54, 3.26). Also, in-school adolescents who were bullied (aOR=1.85; 95% CI 1.24, 2.76), ever engaged in sexual intercourse (aOR=2.06; 95% CI 1.39, 3.06), and used marijuana (aOR=3.36; 95% CI 1.72, 6.53) were more likely to use alcohol compared with those who were not. However, in-school adolescents who reported that their parents understood their problems (aOR=0.52; 95% CI 0.33, 0.82) had a lower likelihood of consuming alcohol. CONCLUSION: Our study has shown that alcohol use is prevalent among in-school adolescents in Sierra Leone. Grade level, experiences of being bullied, history of sexual intercourse, truancy at school, and previous use of marijuana were the factors influencing alcohol use among in-school adolescents. The findings emphasise the necessity of creating school-based health interventions in Sierra Leone that can effectively identify in-school adolescents potentially vulnerable to alcohol-related issues. Also, existing policies and programmes aimed at reducing alcohol use among in-school adolescents need to be strengthened.
Alternative Interventions Against Neglected Tropical Diseases in SSA: Vector Control
(Springer Vienna, 2024) Boakye, Daniel Adjei
Vector control is one of the strategies recommended by the World Health Organization for the control and prevention of the neglected tropical diseases (NTDs) apart from preventive chemotherapy, intensified case management, provision of safe water, sanitation and hygiene, and veterinary public health. Although an integrated approach based on a combination of strategies or one strategy targeting a group of diseases is the preferred approach, the current policy for the global elimination of most of the NTDs is based solely on chemotherapy (Molyneux, Adv Parasitol 61:1–45, 2006; Uniting To Combat NTDs, Delivering on promises & driving progress. Available: http://unitingtocombatntds.org/report/delivering-promises-driving-progress-second-report-uniting-combat-ntds \[Online\]. Accessed 16 May 2014). Dependence on preventive chemotherapy alone without measures to control vectors and intermediate hosts, for vector-borne NTDs like lymphatic filariasis (LF) and onchocerciasis, may not achieve the expected outcome (Bockarie et al., Ann Rev. Entomol 54:469–487, 2009) in the set targeted time frame. Vector control has the potential to play a very important role in the control of NTDs and is increasingly becoming a supplementary intervention strategy. However, it requires the commitment of resources, both financial and human, from disease control programs. There is the need for integration at all levels while adopting the WHO policy guidelines on IVM. Although vector control has been shown to be an effective strategy for the control of vector-borne NTDs (Bockarie et al., Ann Rev. Entomol 54:469–487, 2009; Townson et al., Bull World Health Org 83:942–947, 2005), it is faced with some challenges, major among which are insecticide resistance, multiplicity of vector species, changes in vector behavior, and cost. Further research on insecticide resistance and the effect of vector control on one disease, as, for example, malaria vector control on lymphatic filariasis, is still required.
Anthrax knowledge, perception, and preventive practices of livestock workers and household animal owners in Nigeria
(Elsevier BV, 2025-05-22) Cadmus, Eniola
Anthrax disease outbreak is a significant public health and socioeconomic problem, especially in low and middle-income countries (LMIC) like Nigeria. Inadequate knowledge and poor preventive practices against the disease among livestock workers and household animal owners remain important for disease transmission. Following the recent outbreaks in Nigeria, a cross-sectional study was carried out to assess the knowledge, perception and preventive practices of livestock workers and household animal owners regarding anthrax and the associated socioeconomic implications in Nigeria. A pretested, semi-structured, interviewer-administered questionnaire was used to elicit relevant information from the respondents (n=1025) in seven of the 36 states in Nigeria. Data were analysed using SPSS version 29. Univariate analysis was done and Chi-square test statistics was test for association between the knowledge/perception and other variables. Of the 1025 respondents, 58.6% and 79.9% demonstrated good knowledge and positive perception towards anthrax. However, there were important exposure practices, including a lack of preventive measures against anthrax infection (22.0%). Besides, only 27.7% of the respondents knew about the anthrax vaccination programme for livestock in the study area. With respect to the socioeconomic effects of the disease outbreak, 23.8% of the respondents indicated that the regulations imposed during an anthrax outbreak affect their livestock-related activities, while 40.6% were worried they might go out of business due to the anthrax outbreak. The respondents’ knowledge of anthrax was significantly associated with higher education (p=0.000), level of awareness (p=0.000) and perception of risk (p=0.000). The study reveals a relatively high level of perception but an average knowledge level regarding anthrax with associated socioeconomic impacts among livestock workers and household animal owners in Nigeria. An important knowledge gap includes the poor knowledge of the routine annual vaccination of animals. Hence, mitigation strategies should include educational programmes targeting this gap.
Are malaria transmission-blocking vaccines acceptable to high burden communities? Results from a mixed methods study in Bo, Sierra Leone
(BioMed Central, 2021-04-13) McCoy, Kaci D
BACKGROUND: Malaria transmission-blocking vaccines (TBVs) could help break the cycle of malaria transmission by conferring community rather than individual protection. When introducing new intervention strategies, uptake is dependent on acceptability, not just efficacy. In this exploratory study on acceptability of TBVs in Sierra Leone, it was hypothesized that TBVs would be largely acceptable to adults and health workers in areas with relatively few ongoing malaria interventions, and that (i) knowledge of malaria and vaccines, (ii) health behaviours associated with malaria and vaccines, and (iii) attitudes towards different vaccines types could lead to greater TBV acceptability. METHODS: This study used a mixed methods approach in Bo, Sierra Leone, to understand community knowledge, attitudes, and practices related to malaria and vaccination in general. This included: (i) a population-based cross-sectional survey (n=615 adults), (ii) 6 focus group discussions with parents, and (iii) 20 key informant interviews. The concept of a TBV was explained to participants before they were asked about their willingness to accept this vaccine modality as part of an integrated malaria elimination programme. RESULTS: This study found that most adults would be willing to receive a TBV vaccine. Respondents noted mostly positive past experiences with adult and childhood vaccinations for other infectious diseases and high levels of engagement in other malaria prevention behaviors such as bed nets. Perceived barriers to TBV acceptance were largely focused on general community-level distribution of a vaccine, including personal fears of vaccination and possible costs. After an explanation of the TBV mechanism, nearly all focus group and interview participants believed that community members would accept the vaccine as part of an integrated malaria control approach. Both parents and health workers offered insight on how to successfully roll-out a future TBV vaccination programme. CONCLUSIONS: The willingness of community members in Bo, Sierra Leone to accept a TBV as part of an integrated anti-malarial strategy suggests that the atypical mechanism of TBV action might not be an obstacle to future clinical trials. This study's findings suggests that perceived general barriers to vaccination implementation, such as perceived personal fears and vaccine cost, must be addressed in future clinical and implementation research studies.
Assessing CommCare’s Impact on Antenatal, Postnatal, and Immunization Uptake: Evidence from Falaba Community Health Center, Sierra Leone
(2025-10-01) SAFFA, PHILIP AMARA
Background Rural districts in Sierra Leone struggle with timely and complete maternal–child health service use. CommCare, a mobile health (mHealth) platform deployed through partnerships with government and NGOs, supports tracking, reminders, and follow-up. Methods A cross-sectional quantitative study at Falaba CHC (Sulima Chiefdom) assessed CommCare’s effects on (i) timeliness and frequency of ANC, (ii) PNC follow-up and care quality, and (iii) immunization uptake among children <2 years. Data were collected from n=288 participants using a structured CommCare questionnaire aligned with five sections (A–E) and extracted CommCare indicators; analysis used descriptive statistics and chi square χ² tests (α=0.05), with effect sizes where applicable. Results First-trimester ANC initiation increased from 45% to 65% (χ²=8.34, p =0.004); completion of ≥4 ANC visits rose 55%→78% (χ²=7.72, p =0.009). PNC improved: first-week postpartum follow-up 40%→80% (χ²=6.12, p =0.014). Immunization adherence increased 60%→82% (χ²=11.34, p =0.002); missed vaccination appointments declined by 24%. CommCare reminders showed strong associations with timely attendance (e.g., PNC χ²=28.451, p <0.001) and fewer missed immunization appointments (χ²=55.524, p <0.001; Φ=−0.439, Cramér’s V=0.439). Conclusion CommCare substantially improved timeliness and continuity of maternal and child health services at Falaba CHC. Findings support CHW-mediated, reminder-driven mHealth as an effective strategy in similar rural settings. Author Summary This study evaluates the role of CommCare , a mobile health (mHealth) platform, in improving maternal and child health service uptake at Falaba Community Health Center in Sierra Leone—a rural district marked by logistical, cultural, and infrastructural barriers to care. Using a cross-sectional quantitative design with 288 participants, the study assessed CommCare’s effect on antenatal care (ANC), postnatal care (PNC), and immunization adherence. Findings demonstrate consistent and significant gains across the continuum of care. First-trimester ANC initiation improved from 45% to 65%, and completion of at least four visits rose from 55% to 78%. PNC attendance within the first week postpartum doubled from 40% to 80%. Immunization adherence increased from 60% to 82%, while missed appointments declined by nearly a quarter. Strong associations were observed between CommCare reminders and timely service use, with most respondents rating the reminders as “extremely useful.” Importantly, the intervention’s impact was mediated through community health workers (CHWs), meaning phone ownership was not a barrier to equitable reach. These results highlight CommCare’s potential as a scalable, CHW-mediated digital tool to strengthen rural health systems by enhancing timeliness, continuity, and confidence in maternal–child healthcare. However, persistent gaps such as transport barriers, socio-economic constraints, and limited health system capacity suggest that digital reminders must be complemented by structural supports for sustained impact. The study contributes to the evidence base on mHealth in low-resource settings, underscoring that digital interventions are most effective when embedded into health system workflows and coupled with investments in CHWs, logistics, and culturally attuned communication strategies.
Attitudes toward home-based malaria testing in rural and urban Sierra Leone
(BioMed Central, 2015-02-15) Ranasinghe, Shamika
BACKGROUND: The purpose of this study was to examine malaria testing practices and preferences in Bo, Sierra Leone, and to ascertain interest in and willingness to take a home-based rapid diagnostic test administered by a community health volunteer (CHV) or a trained family member rather than travelling to a clinical facility for laboratory-based testing. METHODS: A population-based, cross-sectional survey of 667 randomly-sampled rural households and 157 urban households was conducted in December 2013 and January 2014. RESULTS: Among rural residents, 69% preferred a self/family- or CHV-conducted home-based malaria test and 20% preferred a laboratory-based test (with others indicating no preference). Among urban residents, these numbers were 38% and 44%, respectively. If offered a home-based test, 28% of rural residents would prefer a self/family-conducted test and 68% would prefer a CHV-assisted test. For urban residents, these numbers were 21% and 77%. In total, 36% of rural and 63% of urban residents reported usually taking a diagnostic test to confirm suspected malaria. The most common reasons for not seeking malaria testing were the cost of testing, waiting to see if the fever resolved on its own, and not wanting to travel to a clinical facility for a test. In total, 32% of rural and 27% of urban participants were very confident they could perform a malaria test on themselves or a family member without assistance, 50% of rural and 62% of urban participants were very confident they could perform a test after training, and 56% of rural and 33% of urban participants said they would pay more for a home-based test than a laboratory-based test. CONCLUSION: Expanding community case management of malaria to include home testing by CHVs and family members may increase the proportion of individuals with febrile illnesses who confirm a positive diagnosis prior to initiating treatment.
Beyond Vaccine: Expanding the Frontiers of Community Action Network in Mitigating Mpox Outbreaks in Africa
(2024-10-31) Cadmus, Simeon
Biomedical knowledge gaps, supernatural causal beliefs and the traditional-first treatment pathway sustaining onchocerciasis transmission despite mass drug administration in Bo District, Sierra Leone: an explanatory sequential mixed-methods study
(openRxiv, 2026-06-22) Moseray, Augustine B
Onchocerciasis (river blindness) persists in Bo District, Sierra Leone, despite two decades of ivermectin-based mass drug administration (MDA). Whether community knowledge, causal beliefs and treatment-seeking continue to favour transmission has not been quantified at scale. Using an explanatory sequential mixed-methods design, we surveyed 1,500 adults across five endemic chiefdoms (Bagbwe, Baoma, Gbo, Selenga, Tikonko) using multistage cluster sampling, and conducted 11 key informant interviews and 8 focus group discussions analysed thematically. Biomedical perception was measured with closed items summed into a composite score (range 0–3); the principal behavioural outcome was traditional-first treatment (use of traditional remedies before modern care). Quantitative data were analysed with chi-square tests, logistic regression, and ROC analysis. Biomedical understanding was moderate and incomplete: only 46.5% correctly identified the blackfly vector and 38.1% judged community awareness sufficient, while supernatural or moral attributions accounted for 68.1% of social explanations and half the sample (50.3%) endorsed a traditional or spiritual origin (mean composite perception 1.77/3). Perception did not vary across chiefdoms (all Cramér’s V < .06); the only consistent correlate was prior experience of the disease, which raised the odds of adequate perception (OR = 0.77 for inadequate perception, p = .016). Traditional-first treatment was the modal pathway (55.3%), care-seeking was reactive (70.1% acted only on symptom onset) and socially governed (71.3% consulted family or peers), and traditional healers were present in most communities (56.9%). A flagship logistic model predicting traditional-first treatment had negligible explanatory power (McFadden R² = .005; likelihood-ratio p = .737; AUC = 0.544), with only distrust of modern medicine showing a directional effect (OR = 1.33, p = .065). Qualitative accounts explained these patterns as a coherent cultural logic rather than ignorance, rooted in naming the disease for water, spiritual aetiologies, the invisibility of the parasite, and the complementary role of healers. Aetiology-aligned health communication, engagement of traditional healers and gender-sensitive MDA delivery are needed to close the residual transmission gap.
Building diagnostic systems in Sierra Leone: The role of point-of-care devices in laboratory strengthening
(AOSIS, 2020-04-01) Ansumana, Rashid
The 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.
Caesarean section rates and obstetric practices in Sierra Leone before, during, and after the Ebola epidemic: Results from a nationwide household study
(SAGE Publishing, 2026-08-01) Westendorp, Josien
BackgroundThrough health system reforms Sierra Leone has achieved reductions from 1,603 to 354 maternal deaths per 100,000 live births between 2000 and 2023, but progress has been uneven and severely disrupted by the 2013-2016 Ebola virus disease (EVD) outbreak. National surveys track key maternal health indicators but provide limited insight into assisted vaginal delivery and women's access to emergency obstetric care, including caesarean section, during and after health system shocks.ObjectivesTo describe patterns of caesarean section and assisted vaginal delivery, place and mode of transport for childbirth before, during, and after the EVD outbreak from a community perspective, and assess changes compared with earlier nationwide household study data.DesignCross-sectional household survey.MethodsA district and urban-rural weighted random cluster design selected enumerator areas with probability proportional to population size. Women aged 12-50 years provided obstetric histories. Data were compared with the 2012 household survey using the same methodology and interpreted in the context of national health system initiatives and the EVD outbreak timeline. Descriptive statistics and chi-square tests examined differences across time periods.ResultsAmong 914 women with 2,094 pregnancies, caesarean section rates rose from 1.6% pre-to 3.7% post-EVD, while assisted vaginal delivery dropped to zero during the outbreak and re-emerged at 2.9%. Facility births increased from 57.6% pre-to 73.8% post-EVD, with home deliveries declining to 16.3%. Almost half of women delivering post-EVD reached facilities on foot, and ambulance use remained minimal. No substantial improvement was observed in girls' education and literacy over the decade.ConclusionObstetric service use in Sierra Leone continued to improve after the EVD outbreak, but transport barriers and low assisted vaginal delivery and caesarean section rates persist. Strengthening girls' education, referral systems, emergency obstetric capacity and skills retention remain essential for resilient, equitable maternal care.
Cardiovascular disease risk profile and management among people 40 years of age and above in Bo, Sierra Leone: A cross-sectional study
(Public Library of Science, 2022-09-09) Odland, Maria Lisa
INTRODUCTION: Access to care for cardiovascular disease risk factors (CVDRFs) in low- and middle-income countries is limited. We aimed to describe the need and access to care for people with CVDRF and the preparedness of the health system to treat these in Bo, Sierra Leone. METHODS: Data from a 2018 household survey conducted in Bo, Sierra Leone, was analysed. Demographic, anthropometric and clinical data on CVDRF (hypertension, diabetes mellitus or dyslipidaemia) from randomly sampled individuals 40 years of age and above were collected. Future risk of CVD was calculated using the World Health Organisation-International Society of Hypertension (WHO-ISH) calculator with high risk defined as >20% risk over 10 years. Requirement for treatment was based on WHO package of essential non-communicable (PEN) disease guidelines (which use a risk-based approach) or requiring treatment for individual CVDRF; whether participants were on treatment was used to determine whether care needs were met. Multivariable regression was used to test associations between individual characteristics and outcomes. Data from the most recent WHO Service Availability and Readiness Assessment (SARA) were used to create a score reflecting health system preparedness to treat CVDRF, and compared to that for HIV. RESULTS: 2071 individual participants were included. Most participants (n = 1715 \[94.0%\]) had low CVD risk; 423 (20.6%) and 431 (52.3%) required treatment based upon WHO PEN guidelines or individual CVDRF, respectively. Sixty-eight (15.8%) had met-need for treatment determined by WHO guidelines, whilst 84 (19.3%) for individual CVDRF. Living in urban areas, having education, being older, single/widowed/divorced, or wealthy were independently associated with met need. Overall facility readiness scores for CVD/CVDRF care for all facilities in Bo district was 16.8%, compared to 41% for HIV. CONCLUSION: The number of people who require treatment for CVDRF in Sierra Leone is substantially lower based on WHO guidelines compared to CVDRF. CVDRF care needs are not met equitably, and facility readiness to provide care is low.
CHANGING DROUGHT PATTERNS IN SIERRA LEONE UNDER A WARMING CLIMATE: A SPATIOTEMPORAL ANALYSIS OF METEOROLOGICAL AND CLIMATIC WATER DEFICITS FROM 1981 TO 2025
(Jana Publication and Research LLP, 2026-09-30) Brima Gogra, Alhaji
Drought is a significant climate-related hazard in Sierra Leone due to the countrys reliance on seasonal rainfall, rain-fed agriculture, and climate-sensitive water resources. This study examines evidence of meteorological and climatic water deficits during 1981-2025 using the Standardized Precipitation Index (SPI) and Standardized Precipitation-Evapotranspiration Index (SPEI), with precipitation data from the Climatic Research Unit ( CRU ) and temperature data from ERA5, complemented by externally produced CORDEX - Africa/ CMIP projections and published assessments. The evidence indicates substantial spatial and temporal variability in drought frequency, duration, severity, and exposure, with northern areas such as Kambia and Port Loko identified in previous studies as comparatively drought-sensitive because of rainfall variability, warming, and dependence on rain-fed agriculture. Importantly, reported quantitative estimates from Amara and Ullah (2023), the Green Climate Fund (2024), Ekolu et al. (2025), Ogunrinde et al. (2026), and other sources are treated explicitly as secondary evidence rather than newly calculated results, and climate projections are interpreted within their original modelling and scenario frameworks.
Characterization of insecticide resistance mechanisms in the Anopheles gambiae population of Sierra Leone
(BioMed Central, 2025-03-13) Opondo, Kevin Ochieng'
BACKGROUND: Information on the status of insecticide resistance in malaria vectors is critical for implementing effective malaria vector control. The Sierra Leone National Malaria Control Programme, in collaboration with the PMI VectorLink project, assessed the resistance status to insecticides commonly used in public health, and associated resistance mechanisms in Anopheles gambiae, the main vector of malaria in Sierra Leone. METHODS: The susceptibility of An. gambiae against pyrethroids with and without piperonyl butoxide (PBO), chlorfenapyr, clothianidin, bendiocarb and pirimiphos-methyl was evaluated in four districts of Sierra Leone in 2018 and 2019 using WHO and CDC bottle bioassay protocols. A subset of samples that were exposed to the insecticides were screened for molecular markers of insecticide resistance, knock-down resistance (kdr) L1014F, 1014S and N1575Y, and (ace-1-G119S). RESULTS: Anopheles gambiae from all sites were resistant to the diagnostic doses of three pyrethroids: deltamethrin, permethrin and alpha-cypermethrin. Intensity of resistance to all three pyrethroids was high, with less than 95% mortality at 10X concentration. However, pre-exposure of An. gambiae to PBO increased overall mortality by 41.6%, 50.0% and 44.0% for deltamethrin, permethrin and alpha-cypermethrin, respectively. The vector was susceptible to chlorfenapyr, clothianidin and pirimiphos-methyl, while bendiocarb showed possible resistance. The frequency of kdr alleles was 98.2% for L1014F, 2.1% for 1014S and 8.9% for N1575Y, while the frequency of the Ace-1 G119S allele was 13.6%. Significant deviation from the Hardy-Weinberg equilibrium and deficiency of heterozygotes was detected only at the G119S locus of An. gambiae (p < 0.0001). Of the 191 An. gambiae sensu lato that were molecularly identified to the species level, 81.7% were An. gambiae sensu stricto (95% CI 75.3-86.7), followed by Anopheles coluzzii (17.8%, 95% CI (12.8-24.1) with one hybrid of An. gambiae/An. coluzzii 0.5%, 95% CI (0.03-3.3). CONCLUSION: Malaria vectors were highly resistant to pyrethroids but exposure to PBO partially restored susceptibility in An. gambiae s.l. in Sierra Leone. Malaria vectors were susceptible to chlorfenapyr, clothianidin and pirimiphos-methyl with possible resistance to bendiocarb. These data informed the selection and distribution of ITN PBO in Sierra Leone's mass campaigns in 2020 and selection of clothianidin for indoor residual spraying in 2021.
Characterization of the first complete genome sequence of yellow fever virus (YFV) in Sierra Leone: Implications for public health
(Public Library of Science, 2026-05-18) Sandi, John Demby
Yellow fever virus (YFV), a mosquito-borne orthoflavivirus that causes severe hemorrhagic disease, is endemic in parts of South America and Africa, yet genomic data from Sierra Leone is lacking despite ongoing case-based surveillance. Using hybrid-capture metagenomic sequencing, we generated a complete 10,611 nt YFV genome (98% coverage) from an adult male patient who reported to the Kailahun Government Hospital with fever and muscle pain. Phylogenetic analysis assigned the genome to the West African II genotype via the YFV Nextstrain build. The Sierra Leone genome showed 57 substitutions, three of which were non-synonymous (NS2B: N79S, NS3: V515I, and NS5 (RdRp domain): A643V), relative to its most recent common ancestor with other genomes from Senegal and the Netherlands. Bayesian phylogenetics estimated the time to the most recent common ancestor with these genomes as January 14, 2001 (95% HPD: December 17, 1987 - April 28, 2009), potentially indicative of long-standing transmission within West Africa that has not been genomically characterized, rather than specific localization to Sierra Leone. Together, these findings underscore the need for expanded genomic surveillance to monitor YFV spread and evolution.
Characterization of the First Complete Genome Sequence of Yellow Fever Virus (YFV) isolate in Sierra Leone: Implications for Public Health
(2025-12-06) Sandi, John Demby
Yellow fever virus (YFV), a mosquito-borne flavivirus that causes severe hemorrhagic disease, is endemic in parts of South America and Africa, yet genomic data from Sierra Leone is lacking despite ongoing surveillance. Using hybrid-capture metagenomic sequencing, we generated a complete 10,611-bp YFV genome (98% coverage) from an adult male patient who reported to the Kailahun Government Hospital with fever and muscle pain. Phylogenetic analysis assigned the genome to West African Clade V via the YFV Nextstrain build. Compared with other West African isolates, the Sierra Leone genome contained 57 substitutions, three of which were non-synonymous (NS2b: N79S, NS3: V515I, and RdRp: A643V). Bayesian phylogenetics estimated the time to the most recent common ancestor with the closest sequences from Senegal and the Netherlands as January 14, 2001 (95% HPD: December 17, 1987 - April 28, 2009), suggesting long-standing, cryptic transmission. Together, these findings underscore the need for expanded genomic surveillance to monitor YFV spread, evolution, and potential impacts on vaccine performance.
Child bed net use before, during, and after a bed net distribution campaign in Bo, Sierra Leone
(BioMed Central, 2015-11-18) Ranasinghe, Shamika
BACKGROUND: This analysis examined how the proportion of children less than 5-years-old who slept under a bed net the previous night changed during and after a national long-lasting insecticidal net (LLIN) distribution campaign in Sierra Leone in November-December 2010. METHODS: A citywide cross-sectional study in 2010-2011 interviewed the caregivers of more than 3000 under-five children from across urban Bo, Sierra Leone. Chi squared tests were used to assess change in use rates over time, and multivariate regression models were used to examine the factors associated with bed net use. RESULTS: Reported rates of last-night bed net use changed from 38.7 % (504/1304) in the months before the LLIN campaign to 21.8 % (78/357) during the week of the campaign to 75.3 % (1045/1387) in the months after the national campaign. The bed net use rate significantly increased (p < 0.01) from before the campaign to after the universal LLIN distribution campaign in all demographic, socioeconomic, and health behaviour groups, even though reported use during the campaign dropped significantly. CONCLUSION: Future malaria prevention efforts will need to promote consistent use of LLINs and address any remaining disparities in insecticide-treated bed net (ITN) use.