Background: Identification of local Plasmodium vivax transmission foci and its hidden reservoirs are crucial to eliminating residual vivax malaria transmission. This study assessed whether reactive case detection (RCD) could better identify P. vivax cases and infection incidences in Arjo-Didessa, Southwestern Ethiopia.
View Article and Find Full Text PDFAm J Trop Med Hyg
October 2024
Background: To interrupt residual malaria transmission and achieve successful elimination of Plasmodium falciparum in low-transmission settings, the World Health Organization (WHO) recommends the administration of a single dose of 0.25 mg/kg (or 15 mg/kg for adults) primaquine (PQ) combined with artemisinin-based combination therapy (ACT), without glucose-6-phosphate dehydrogenase (G6PD) testing. However, due to the risk of haemolysis in patients with G6PD deficiency (G6PDd), PQ use is uncommon.
View Article and Find Full Text PDFBackground: Changing cell-type proportions can confound studies of differential gene expression or DNA methylation (DNAm) from peripheral blood mononuclear cells (PBMCs). We examined how cell-type proportions derived from the transcriptome versus the methylome (DNAm) influence estimates of differentially expressed genes (DEGs) and differentially methylated positions (DMPs).
Methods: Transcriptome and DNAm data were obtained from PBMC RNA and DNA of Kenyan children (n = 8) before, during, and 6 weeks following uncomplicated malaria.
Background: Changing cell-type proportions can confound studies of differential gene expression or DNA methylation (DNAm) from peripheral blood mononuclear cells (PBMCs). We examined how cell-type proportions derived from the transcriptome versus the methylome (DNAm) influence estimates of differentially expressed genes (DEGs) and differentially methylated positions (DMPs).
Methods: Transcriptome and DNAm data were obtained from PBMC RNA and DNA of Kenyan children (n = 8) before, during, and 6 weeks following uncomplicated malaria.
Background: To interrupt residual malaria transmission and achieve successful elimination of in low-transmission settings, the World Health Organization (WHO) recommends the administration of a single dose of 0.25 mg/kg (or 15 mg/kg for adults) primaquine (PQ) combined with artemisinin-based combination therapy (ACT) without glucose-6-phosphate dehydrogenase (G6PD) testing. However, due to the risk of hemolysis in patients with G6PD deficiency (G6PDd), PQ use is not as common.
View Article and Find Full Text PDFBackground: Malaria remains a significant cause of morbidity and mortality in Ethiopia with an estimated 3.8 million cases in 2021 and 61% of the population living in areas at risk of malaria transmission. Throughout the country Plasmodium vivax and Plasmodium falciparum are co-endemic, and Duffy expression is highly heterogeneous.
View Article and Find Full Text PDFBackground: Understanding of malaria ecology is a prerequisite for designing locally adapted control strategies in resource-limited settings. The aim of this study was to utilize the spatial heterogeneity in malaria transmission for the designing of adaptive interventions.
Methods: Field collections of clinical malaria incidence, asymptomatic Plasmodium infection, and malaria vector data were conducted from 108 randomly selected clusters which covered different landscape settings including irrigated farming, seasonal flooding area, lowland dryland farming, and highlands in western Kenya.
Background: Understanding the clustering of infections for persistent malaria transmission is critical to determining how and where to target specific interventions. This study aimed to determine the density, blood meal sources and malaria transmission risk of anopheline vectors by targeting malaria index cases, their neighboring households and control villages in Arjo-Didessa, southwestern Ethiopia.
Methods: An entomological study was conducted concurrently with a reactive case detection (RCD) study from November 2019 to October 2021 in Arjo Didessa and the surrounding vicinity, southwestern Ethiopia.
Despite historical dogma that Duffy blood group negativity of human erythrocytes confers resistance to Plasmodium vivax blood stage infection, cases of P. vivax malaria and asymptomatic blood stage infection (subclinical malaria) have recently been well documented in Duffy-negative individuals throughout Africa. However, the impact of Duffy negativity on the development of naturally acquired immunity to P.
View Article and Find Full Text PDFBackground: Malaria remains a significant cause of morbidity and mortality in Ethiopia with an estimated 4.2 million annual cases and 61% of the population living in areas at risk of malaria transmission. Throughout the country and are co-endemic, and Duffy expression is highly heterogeneous.
View Article and Find Full Text PDFBackground: The rise of insecticide resistance against malaria vectors in sub-Saharan Africa has resulted in the need to consider other methods of vector control. The potential use of biological methods, including larvivorous fish, Bacillus thuringiensis israelensis (Bti) and plant shading, is sustainable and environmentally friendly options. This study examined the survivorship of Anopheles arabiensis and Anopheles funestus larvae and habitat productivity in four permanent habitat types in Homa Bay county, western Kenya.
View Article and Find Full Text PDFFront Cell Infect Microbiol
September 2023
Malaria is a parasitic disease of global health significance and a leading cause of death in children living in endemic regions. Although various Plasmodium species are responsible for the disease, infection accounts for most severe cases of the disease in humans. The mechanisms of cerebral malaria pathogenesis have been studied extensively in humans and animal malaria models; however, it is far from being fully understood.
View Article and Find Full Text PDFAccurate malaria diagnosis and timely treatment are requirements for effective management of the disease. However, treatment efficacy may be significantly reduced in resource-constrained healthcare facilities with poorly equipped laboratories and frequent drug and rapid diagnostic test kit (RDT) stock-outs. Furthermore, patient may avoid seeking treatment from such facilities.
View Article and Find Full Text PDFKnowledge of insect dispersal is relevant to the control of agricultural pests, vector-borne transmission of human and veterinary pathogens, and insect biodiversity. Previous studies in a malaria endemic area of the Sahel region in West Africa revealed high-altitude, long-distance migration of insects and various mosquito species. The objective of the current study was to assess whether similar behavior is exhibited by mosquitoes and other insects around the Lake Victoria basin region of Kenya in East Africa.
View Article and Find Full Text PDFProgress in malaria control has stalled over the recent years. Knowledge on main drivers of transmission explaining small-scale variation in prevalence can inform targeted control measures. We collected finger-prick blood samples from 3061 individuals irrespective of clinical symptoms in 20 clusters in Busia in western Kenya and screened for Plasmodium falciparum parasites using qPCR and microscopy.
View Article and Find Full Text PDFAs malaria control and elimination efforts ramp up in Ethiopia, more sensitive tools for assessing exposure to coendemic Plasmodium falciparum and Plasmodium vivax are needed to accurately characterize malaria risk and epidemiology. Serological markers have been increasingly explored as cost-effective tools for measuring transmission intensity and evaluating intervention effectiveness. The objectives of this study were to evaluate the efficacy of a panel of 10 serological markers as a proxy for malaria exposure and to determine underlying risk factors of seropositivity.
View Article and Find Full Text PDFBackground: Water resource development projects such as dams and irrigation schemes have a positive impact on food security and poverty reduction but might result in increased prevalence of malaria.
Methods: Two cross-sectional surveys were conducted in the dry and wet seasons in irrigated and non-irrigated clusters of Arjo sugarcane and Gambella rice development areas of Ethiopia in 2019. A total of 4464 and 2176 blood samples were collected from Arjo and Gambella.
Background: Malaria in western Kenya is currently characterized by sustained high Plasmodial transmission and infection resurgence, despite positive responses in some areas following intensified malaria control interventions since 2006. This study aimed to evaluate long-term changes in malaria transmission profiles and to assess patterns of asymptomatic malaria infections in school children aged 5-15 years at three sites in western Kenya with heterogeneous malaria transmission and simultaneous malaria control interventions.
Methods: The study was conducted from 2018 to 2019 and is based on data taken every third year from 2005 to 2014 during a longitudinal parasitological and mosquito adult surveillance and malaria control programme that was initiated in 2002 in the villages of Kombewa, Iguhu, and Marani.
Several sub-Saharan African countries rely on irrigation for food production. This study examined the impact of environmental modifications resulting from irrigation on the ecology of aquatic stages of malaria vectors in a semi-arid region of western Kenya. Mosquito larvae were collected from irrigated and non-irrigated ecosystems during seasonal cross-sectional and monthly longitudinal studies to assess habitat availability, stability, and productivity of anophelines in temporary, semipermanent, and permanent habitats during the dry and wet seasons.
View Article and Find Full Text PDFFood insecurity, recurrent famine, and poverty threaten the health of millions of African residents. Construction of dams and rural irrigation schemes is key to solving these problems. The sub-Saharan Africa International Center of Excellence for Malaria Research addresses major knowledge gaps and challenges in Plasmodium falciparum and Plasmodium vivax malaria control and elimination in malaria-endemic areas of Kenya and Ethiopia where major investments in water resource development are taking place.
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