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1.
APMIS ; 2024 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-39370672

RESUMEN

The Central African Republic (CAR) is characterized by widespread HIV epidemic with notable prevalence and genetic diversity. We herein analysed the genetic diversity of atypical non-M HIV-1 strains. In-house serotyping assays for variants of HIV-1 (M, N, O, P) and HIV-2 were used to test a biological collection of 6092 HIV-seropositive blood samples collected between 2003 and 2014 at the Institut Pasteur de Bangui. Samples indicative of recombinant M/O groups, HIV-2, or those that yield doubtful/negative results underwent further PCR tests and sequencing. We found six atypical HIV strains: specifically, three (0.05%) HIV-1 group O strains (subtype H) detected in samples from 2005, 2008 and 2009, alongside three (0.05%) HIV-2 strains (two group A and one group B) identified in samples from 2007 and 2009. HIV-1/O strains showed a genetic link to Cameroon and Gabon strains. This study highlights the dominance of HIV-1/M in the CAR's HIV epidemic over time and underscores the infrequent occurrence of HIV-1 group O and HIV-2 strains. These findings validate the efficacy of WHO-recommended HIV testing protocols and emphasize the need for adaptive surveillance and management strategies to confront the complexities introduced by the genetic diversity of HIV strains.

2.
Afr J Reprod Health ; 28(8s): 15-20, 2024 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-39269211

RESUMEN

The West and Central Africa (WCA) region is a natural resource-rich, 24-country, contiguous area with a population of nearly 500 million people. The median age for the region is currently 18 years and approximately one-third of its population is aged between 10 and 24 years. If current demographic trends in the region persist, its population will reach 1.5 billion by 2050. At that time, WCA will not only have the largest number of young people globally, but it will also be the only part of the world whose population of young people will continue to increase1. Many countries in the region are also or have recently been involved in armed conflicts, which have devastated infrastructure, displaced people, stifled development, and more importantly, resulted in myriad deaths and morbidities.


La région de l'Afrique de l'Ouest et du Centre (AOC) est une zone contiguë de 24 pays riches en ressources naturelles et comptant près de 500 millions d'habitants. L'âge médian de la région est actuellement de 18 ans et environ un tiers de sa population est âgée de 10 à 24 ans. Si les tendances démographiques actuelles de la région persistent, la population de la région atteindra 1,5 milliard d'habitants d'ici 2050. À cette époque, l'AOC comptera non seulement le plus grand nombre de jeunes au monde, mais elle sera également la seule partie du monde dont la population de le nombre de jeunes va continuer à augmenter1. De nombreux pays de la région sont également ou ont été récemment impliqués dans des conflits armés, qui ont dévasté les infrastructures, déplacé les populations, étouffé le développement et, plus important encore, entraîné une myriade de morts et de morbidités.


Asunto(s)
Salud Reproductiva , Derechos Sexuales y Reproductivos , Salud Sexual , Humanos , Adolescente , África Central/epidemiología , Femenino , África Occidental/epidemiología , Masculino , Conducta Sexual , Salud del Adolescente , Niño , Adulto Joven
3.
F1000Res ; 13: 642, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39290845

RESUMEN

Background: Traditionally in the Democratic Republic of the Congo (DRC), centralised Ebola treatment centres (ETCs) have been set exclusively for Ebola virus disease (EVD) case management during outbreaks. During the 2020 EVD outbreak in DRC's Equateur Province, existing health centres were equipped as decentralised treatment centres (DTC) to improve access for patients with suspected EVD. Between ETCs and DTCs, we compared the time from symptom onset to admission and diagnosis among patients with suspected EVD. Methods: This was a cohort study based on analysis of a line-list containing demographic and clinical information of patients with suspected EVD admitted to any EVD health facility during the outbreak. Results: Of 2359 patients with suspected EVD, 363 (15%) were first admitted to a DTC. Of 1996 EVD-suspected patients initially admitted to an ETC, 72 (4%) were confirmed as EVD-positive. Of 363 EVD-suspected patients initially admitted to a DTC, 6 (2%) were confirmed and managed as EVD-positive in the DTC. Among all EVD-suspected patients, the median (interquartile range) duration between symptom onset and admission was 2 (1-4) days in a DTC compared to 4 (2-7) days in an ETC (p<0.001). Similarly, time from symptom onset to admission was significantly shorter among EVD-suspected patients ultimately diagnosed as EVD-negative. Conclusions: Since <5% of the EVD-suspected patients admitted were eventually diagnosed with EVD, there is a need for better screening to optimise resource utilization and outbreak control. Only one in seven EVD-suspected patients were admitted to a DTC first, as the DTCs were piloted in a limited and phased manner. However, there is a case to be made for considering decentralized care especially in remote and hard-to-reach areas in places like the DRC to facilitate early access to care, contain viral shedding by patients with EVD and ensure no disrupted provision of non-EVD services.


Asunto(s)
Brotes de Enfermedades , Fiebre Hemorrágica Ebola , Humanos , República Democrática del Congo/epidemiología , Fiebre Hemorrágica Ebola/epidemiología , Fiebre Hemorrágica Ebola/terapia , Masculino , Femenino , Adulto , Persona de Mediana Edad , Adolescente , Adulto Joven , Estudios de Cohortes , Niño , Atención a la Salud/organización & administración , Ebolavirus
4.
Insects ; 15(8)2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39194765

RESUMEN

Aedes albopictus (Skuse, 1894), a mosquito originating in Asia, has been introduced to Africa since the 2000s. The mosquito is not only a nuisance but is capable of transmitting various arboviruses. The current study summarized our entomological surveys in the Democratic Republic of Sao Tome and Principe during 2000 to 2016. Adult mosquitoes were collected by sweep nets, human landing catches, and Centers for Disease Control (CDC) light traps, and the immatures were collected from water-filled habitats at 15 sentinel sites and reared to adulthood. Species identification was performed based on morphologic characteristics. Fragments of the cytochrome C oxidase subunit I (COI) and the Wolbachia surface protein (wsp) genes were amplified for mosquitoes collected in Principe. New records of four mosquito species were reported. Aedes albopictus was identified in 2015. The larvae were found distributed over the nation and were predominately in artificial water-holding containers (488/2698, 18.1%). The highest positive rate was observed in used tires in Príncipe (114/250, 45.6%). Mitochondrial DNA analysis revealed low genetic diversity among the invasive populations, but all tested specimens were superinfected by Wolbachia. The ability of Ae. albopictus to adapt to new environments and its involvement in disease transmission make the surveillance and control of this species particularly important.

5.
J Infect Dis ; 2024 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-39126336

RESUMEN

BACKGROUND: Ebola (EBOV) and Sudan (SUDV) orthoebolaviruses are responsible for lethal haemorrhagic fever outbreaks in humans in Central and West Africa, and in apes that can be at the source of human outbreaks for EBOV. METHODS: To assess the risk of exposure to orthoebolaviruses through contact with non-human primates (NHP), we tested the presence of antibodies against different viral proteins with a microsphere-based multiplex immunoassay in a case-control study on bites from NHPs in forest areas from Cameroon (n=795), and in cross-sectional surveys from other rural populations (n=622) of the same country. RESULTS: Seroreactivities against at least two viral proteins were detected in 13% and 12% of the samples for EBOV and SUDV, respectively. Probability of seroreactivity was not associated with history of NHP bites, but was three times higher in Pygmies compared to Bantus. Although no neutralizing antibodies to EBOV and SUDV were detected in a selected series of highly reactive samples, avidity results indicate strong affinity to SUDV antigens. CONCLUSION: The detection of high level of seroreactivities against orthoebolaviruses in rural Cameroon where no outbreaks have been reported, raises the possibilities of silent circulation of orthoebolavirus, or of other not yet documented filoviruses, in these forested regions.

6.
Nutrients ; 16(16)2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39203938

RESUMEN

Food insecurity (FI) is a critical socioeconomic and public health problem globally, particularly affecting children's nutritional status and development. This cross-sectional study aimed to assess the prevalence of nutritional inadequacy among children and adolescents in the Cantagalo district of São Tomé and Príncipe (STP), in Central Africa. It also assessed their households' FI situation and examined sociodemographic, anthropometric, and nutritional characteristics associated with severe FI. Data included 546 children/adolescents (51.8% males, aged 9-15 years) from the eight public basic education schools. A structured questionnaire provided sociodemographic data, while anthropometric measurements assessed nutritional status. Dietary intake data were gathered using a single 24 h dietary recall, and the adjusted prevalences of nutritional inadequacy were obtained using version 2.0 of the PC-Software for Intake Distribution Estimation (PC-SIDE®). The Household Food Insecurity Access Scale was used to assess FI, and households were classified as severely or non-severely food insecure. Multivariable binary logistic regression models adjusted for potential confounders identified factors related to FI. Children's/adolescents' thinness was exhibited in 34.1% of participants, and over 95% had inadequate intake of essential micronutrients, including iron. Notably, 73.7% were severely food insecure. A higher severity of FI was positively associated with a lower intake of iron and certain household head characteristics, such as being female or older, and negatively associated with having a home garden.


Asunto(s)
Inseguridad Alimentaria , Estado Nutricional , Humanos , Niño , Femenino , Masculino , Adolescente , Estudios Transversales , Desnutrición/epidemiología , Instituciones Académicas , Factores Socioeconómicos , Prevalencia , Dieta/estadística & datos numéricos
7.
Am J Biol Anthropol ; 185(2): e24997, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39073316

RESUMEN

INTRODUCTION: Our knowledge of the populations of sub-Saharan Africa in the periods before European colonization is limited. Few archeological sites containing human remains have been identified, and written sources for these periods are rare. The discovery in 2018 of the Iroungou sepulchral cave (Gabon), whose use predates the arrival of the Portuguese (14th-15th centuries CE), is an exceptional source of information: at least 28 individuals associated with numerous metal artifacts were found there. The anthropobiological remains were left in situ, but the eight best preserved crania were digitized. OBJECTIVES: This study focuses on the population affinities of these crania, whose morphology was described using 237 landmarks. MATERIALS AND METHODS: Geometric morphometric analyses were used to compare the eight Iroungou specimens with 154 individuals representing 12 well-defined African populations. After alignment (Generalized Procrustes Analysis), morphological affinity was assessed using Euclidean and Mahalanobis distances, and posterior probabilities of population membership (discriminant analysis). RESULTS: Results indicate that the eight Iroungou crania have, on average, more affinity with Bayaka Pygmy, followed by Central African Bantu. Nevertheless, individually, the Iroungou specimens show an important morphological variation and the eight crania can be separated into different affinity groups: Bayaka and Central African Bantu, KhoeSan, and East-African Bantu. Finally, one individual presents strong affinity with Somalis. CONCLUSION: This phenetic mapping of the Iroungou sample raises questions about the profile of the individuals deposited in the cave in a geographical area known for the Loango pre-colonial kingdom, which ruling class seemed to have had privileged relationships with the Pygmy populations.


INTRODUCTION: Nos connaissances sur les populations d'Afrique sub­saharienne des périodes précédant la colonisation européenne sont limitées. Peu de sites archéologiques contenant des restes humains ont été identifiés, et les sources écrites pour ces périodes sont rares. La découverte en 2018 de la grotte sépulcrale d'Iroungou (Gabon), dont l'utilisation remonte au XIVe­XVe siècles de notre ère, avant l'arrivée des Portugais, constitue une source d'information exceptionnelle: au moins 28 individus associés à de nombreux artefacts métalliques y ont été retrouvés. Les restes anthropobiologiques ont été laissés in situ, néanmoins, les huit crânes les mieux préservés ont été numérisés. OBJECTIFS: Cette étude s'intéresse aux affinités populationnelles de ces crânes, dont la morphologie a été décrite à l'aide de 237 points­repères répartis sur le massif facial supérieur et le calvarium. MATÉRIEL ET MÉTHODES: Des analyses par morphométrie géométrique ont permis de comparer les spécimens d'Iroungou avec 154 individus représentants 12 populations africaines bien définies. Après alignement des conformations (analyse Procrustes généralisée), l'affinité morphologique a été évaluée à l'aide des distances procrustes, euclidienne et mahalanobis, ainsi que des probabilités postérieures d'appartenance à une population (analyse discriminante). RÉSULTATS: Les résultats indiquent que les huit crânes d'Iroungou présentent en moyenne plus d'affinités avec les populations pygmées Bayaka, suivies des Bantus d'Afrique centrale. DISCUSSION: Cette affinité moyenne recouvre une réalité complexe: la population d'Iroungou est la plus hétérogène de notre échantillon et les huit crânes peuvent être séparés en différents groupes d'affinités: avec les Bayakas et les Bantus d'Afrique Centrale, les KhoeSan, et avec les Bantus d'Afrique de l'est. Enfin, un individu présente une affinité très forte avec les Somalis de notre échantillon. Cette cartographie phénétique de la population d'Iroungou interroge sur le profil des individus déposés dans la grotte dans une zone géographique connue le royaume précolonial Loango dont la classe dirigeante semble avoir eu des relations privilégiées avec les populations pygmées.


Asunto(s)
Cuevas , Humanos , Cráneo/anatomía & histología , Masculino , Antropología Física , Femenino , Población Negra/historia , Historia del Siglo XV
8.
Parasitol Res ; 123(7): 277, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39023630

RESUMEN

Malaria caused by Plasmodium falciparum is one of the deadliest and most common tropical infectious diseases. However, the emergence of artemisinin drug resistance associated with the parasite's Pfk13 gene, threatens the public health of individual countries as well as current efforts to reduce malaria burdens globally. It is of concern that artemisinin-resistant parasites may be selected or have already emerged in Africa. This narrative review aims to evaluate the published evidence concerning validated, candidate, and novel Pfk13 polymorphisms in ten Central African countries. Results show that four validated non-synonymous polymorphisms (M476I, R539T, P553L, and P574L), directly associated with a delayed therapy response, have been reported in the region. Also, two Pfk13 polymorphisms associated to artemisinin resistance but not validated (C469F and P527H) have been reported. Furthermore, several non-validated mutations have been observed in Central Africa, and one allele A578S, is commonly found in different countries, although additional molecular and biochemical studies are needed to investigate whether those mutations alter artemisinin effects. This information is discussed in the context of biochemical and genetic aspects of Pfk13, and related to the regional malaria epidemiology of Central African countries.


Asunto(s)
Antimaláricos , Artemisininas , Resistencia a Medicamentos , Malaria Falciparum , Mutación , Plasmodium falciparum , Proteínas Protozoarias , Humanos , África Central/epidemiología , Antimaláricos/farmacología , Artemisininas/farmacología , Malaria Falciparum/parasitología , Malaria Falciparum/epidemiología , Malaria Falciparum/tratamiento farmacológico , Plasmodium falciparum/genética , Plasmodium falciparum/efectos de los fármacos , Polimorfismo Genético , Proteínas Protozoarias/genética
9.
Data Brief ; 55: 110655, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39044909

RESUMEN

After Amazonia, the Congo Basin represents the second-largest tropical rainforest area in the world. This basin harbours remarkable biodiversity, yet much of its microbiological diversity within its waters, soils, and populations remains largely unexplored and undiscovered. While many initiatives to characterize global biodiversity are being undertaken, few are conducted in Africa and none of them concern the Congo Basin specifically in urban areas. In this context, we assessed the microbial diversity present in gutter water in the city of Pointe-Noire, Congo. This town has interesting characteristics as the population density is high and it is located between the Atlantic Ocean and the forest of Mayombe in Central Africa. The findings illuminate the microbial composition of surface water in Pointe-Noire. The dataset allows the identification of putative new bacteria through the assembly of 81 meta-genome-assembled genomes. It also serves as a valuable primary resource for assessing the presence of antibiotic-resistant genes, offering a useful tool for monitoring risks by public health authorities.

10.
Glob Health Action ; 17(1): 2370097, 2024 12 31.
Artículo en Inglés | MEDLINE | ID: mdl-38916612

RESUMEN

BACKGROUND: Investing in midwives educated according to international standards is crucial for achieving Sustainable Development Goals in maternal and newborn health. Applying a person-centred care approach and using simulation-based learning to improve the learning experience for midwifery students may enhance the quality of childbirth care. This protocol describes a study evaluating the implementation of person-centred approach and simulation-based learning in childbirth as part of a midwifery education programme at the Evangelical University in Africa, DRC. METHODS: The research will be exploratory and guided by an implementation research framework. Ethical approval has been obtained. Facilitators working at the programme's five clinical practice sites will be trained in: 1) Introducing person-centred childbirth care using a training programme called'Mutual Meetings'; and 2) integrating simulation-based learning, specifically by using the three courses: Essential Care of Labor, Bleeding after Birth, and Vacuum Extraction. Data will include interviews with midwifery students, facilitators and clinical preceptors, and maternal and neonatal outcomes from birth registers. DISCUSSION: By integrating a validated and culturally adapted person-centred care training programme and simulation-based learning into a midwifery education programme and clinical practice sites, the findings from the study anticipate an improvement in the quality of childbirth care. Training facilitators in these methodologies aim to effectively mitigate maternal and neonatal adverse outcomes. The findings are expected to provide valuable recommendations for governments, policymakers, and healthcare providers in the DRC and beyond, contributing to significant improvements in midwifery education and aligning with global health priorities, including the Sustainable Development Goals. TRIAL REGISTRATION: The study was registered retrospectively with the ISRCTN registry on the 23rd of February 2024. The registration number is: ISRCTN10049855.


Main findings: It is anticipated that the implementation of both person-centred care and simulation-based learning in a midwifery education programme will improve the quality of care in childbirth practice.Added knowledge: The use of facilitators has the potential to enhance the implementation of person-centred care and simulation-based learning in a midwifery education programme, both at campus and in clinic.Global health impact for policy and action: The expected findings could inform global health policy development and practice, promising advancements in midwifery education and consequently enhance the maternal and newborn health outcomes.


Asunto(s)
Partería , Atención Dirigida al Paciente , Humanos , Partería/educación , Atención Dirigida al Paciente/organización & administración , República Democrática del Congo , Femenino , Embarazo , Entrenamiento Simulado/organización & administración , Entrenamiento Simulado/métodos
11.
J Infect Public Health ; 17(8): 102476, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38901117

RESUMEN

BACKGROUND: In Equatorial Guinea, only 54 % of people living with HIV know their HIV status. There are no confirmatory or molecular diagnostic techniques for early diagnosis or monitoring of infection in the country. Rapid diagnostic tests can induce false-positive diagnoses if used as a confirmatory technique. Our study aimed to identify the challenges of early HIV diagnosis in Equatorial Guinea by analyzing the rate of false positive diagnoses, diagnostic and therapeutic delays, and treatment failures among those on antiretroviral therapy. METHODS: From 2019-2022, dried blood from 341 children, adolescents and adults diagnosed in Equatorial Guinea as HIV-positive by rapid diagnostic testing, and from 54 HIV-exposed infants were collected in Bata and sent to Madrid to confirm HIV-infection by molecular (Xpert HIV-1Qual, Cepheid) and/or serological confirmatory assays (Geenius-HIV-1/2, BioRad). HIV diagnostic delay (CD4 <350cells/mm3), advanced disease at diagnosis (CD4 <200cells/mm3) and antiretroviral treatment delay and failure (viraemia >1,000RNA-HIV-1-copies/ml) were also studied after viral quantification (XpertVL HIV-1, Cepheid). RESULTS: False-positive diagnoses were identified in 5 % of analysed samples. HIV infection was confirmed in 90.5 % of previously diagnosed patients in Equatorial Guinea and 3.7 % of HIV-exposed children undiagnosed in the field. Two-thirds of each new HIV patient had delayed diagnosis, and one-third had advanced disease. Treatment delay occurred in 28.3 % of patients, being around four times more likely in adolescents/adults than children. More than half (56 %) of 232 treated patients presented treatment failure, being significantly higher in children/adolescents than in adults (82.9 %/90 % vs. 45.6 %, p < 0.001). CONCLUSION: We identified some challenges of early HIV diagnosis in Equatorial Guinea, revealing a high rate of false positive diagnoses, diagnostic/treatment delays, and treatment failures that need to be addressed. The implementation of more accurate rapid diagnostic techniques and confirmatory tests, along with improving access to care, treatment, awareness, and screening, would contribute to controlling the spread of HIV in the country.


Asunto(s)
Diagnóstico Tardío , Infecciones por VIH , Tiempo de Tratamiento , Humanos , Guinea Ecuatorial , Infecciones por VIH/diagnóstico , Infecciones por VIH/tratamiento farmacológico , Adolescente , Niño , Masculino , Femenino , Adulto , Preescolar , Diagnóstico Tardío/estadística & datos numéricos , Adulto Joven , Lactante , VIH-1/aislamiento & purificación , Reacciones Falso Positivas , Persona de Mediana Edad , Insuficiencia del Tratamiento
12.
Sci Rep ; 14(1): 13131, 2024 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-38849460

RESUMEN

The white-bellied pangolin is subject to intense trafficking, feeding both local and international trade networks. In order to assess its population genetics and trace its domestic trade, we genotyped 562 pangolins from local to large bushmeat markets in western central Africa. We show that the two lineages described from the study region (WCA and Gab) were overlapping in ranges, with limited introgression in southern Cameroon. There was a lack of genetic differentiation across WCA and a significant signature of isolation-by-distance possibly due to unsuspected dispersal capacities involving a Wahlund effect. We detected a c. 74.1-82.5% decline in the effective population size of WCA during the Middle Holocene. Private allele frequency tracing approach indicated up to 600 km sourcing distance by large urban markets from Cameroon, including Equatorial Guinea. The 20 species-specific microsatellite loci provided individual-level genotyping resolution and should be considered as valuable resources for future forensic applications. Because admixture was detected between lineages, we recommend a multi-locus approach for tracing the pangolin trade. The Yaoundé market was the main hub of the trade in the region, and thus should receive specific monitoring to mitigate pangolins' domestic trafficking. Our study also highlighted the weak implementation of CITES regulations at European borders.


Asunto(s)
Repeticiones de Microsatélite , Pangolines , Animales , Pangolines/genética , África Central , Repeticiones de Microsatélite/genética , Genética de Población , Frecuencia de los Genes , Comercio , Genotipo , Camerún , Variación Genética
13.
J West Afr Coll Surg ; 14(2): 174-179, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38562388

RESUMEN

Background: Globally pregnancy and childbirth complications are the leading cause of death among adolescents, with evidence showing that antenatal care (ANC) is a very effective preventive intervention. In Burundi, there is limited information on the extent to which pregnant adolescents utilise such services. Objective: To assess the ANC utilisation and factors associated with its use among adolescent mothers in Ngozi Province, Burundi. Materials and Methods: A cross-sectional, health facility-based study among 216 adolescent mothers who had given birth within two years preceding this study, using structured questionnaires and records from previous ANC booklets. A multistage random sampling technique was used to select respondents while the utilisation of ANC was determined by the frequency of ANC visits and the time when the women enrolled for the first ANC visit. Results: The majority (98.1%) of adolescent mothers in Ngozi Province used ANC services. Most respondents (64.8%) initiated ANC services within the first trimester while 57.8% attained the minimum of four recommended ANC visits. Marital status (P = 0.001), geographical location (P = 0.009), occupation of the partner (P = 0.002) and type of the last pregnancy (P = 0.012) were associated with ANC initiation within the first trimester while marital status (P < 0.001), respondent's employment (P = 0.003) and type of last pregnancy (P < 0.001) were associated with appropriate ANC frequency. Conclusion: This study revealed a high use of ANC services among adolescent mothers, although more than one-third attended ANC late. There is therefore the need to put more effort into improving early booking for ANC.

14.
Environ Monit Assess ; 196(3): 298, 2024 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-38396233

RESUMEN

To anticipate disasters (drought, floods, etc.) caused by environmental forcing and reduce their impacts on its fragile economy, sub-Saharan Africa needs a good knowledge of the availability of current water resources and reliable hydroclimatic forecasts. This study has an objective to quantify the availability of water resources in the Nyong basin and predict its future evolution (2024-2050). For this, the SWAT (Soil and Water Assessment Tool) model was used. The performance of this model is satisfactory in calibration (2001-2005) and validation (2006-2010), with R2, NSE, and KGE greater than 0.64. Biases of - 11.8% and - 13.9% in calibration and validation also attest to this good performance. In the investigated basin, infiltration (GW_RCH), evapotranspiration (ETP), surface runoff (SURQ), and water yield (WYLD) are greater in the East, probably due to more abundant rainfall in this part. The flows and sediment load (SED) are greater in the middle zone and in the Southwest of the basin, certainly because of the flat topography of this part, which corresponds to the valley floor. Two climate models (CCCma and REMO) predict a decline in water resources in this basin, and two others (HIRHAM5 and RCA4) are the opposite. However, based on a statistical study carried out over the historical period (2001-2005), the CCCma model seems the most reliable. It forecasts a drop in precipitation and runoff, which do not exceed - 19% and - 18%, respectively, whatever the emission scenario (RCP4.5 or RCP8.5). Climate variability (CV) is the only forcing whose impact is visible in the dynamics of current and future flows, due to the modest current (increase of + 102 km2 in builds and roads) and future (increase of + 114 km2 in builds and roads) changes observed in the evolution of land use and land cover (LULC). The results of this study could contribute to improving water resource management in the basin studied and the region.


Asunto(s)
Monitoreo del Ambiente , Recursos Hídricos , Camerún , Hidrología , Ríos , Bosques , Cambio Climático , Agua
15.
Emerg Infect Dis ; 30(3): 432-443, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38325363

RESUMEN

During 1979-2022, Cameroon recorded 32 laboratory-confirmed mpox cases among 137 suspected mpox cases identified by the national surveillance network. The highest positivity rate occurred in 2022, indicating potential mpox re-emergence in Cameroon. Both clade I (n = 12) and clade II (n = 18) monkeypox virus (MPXV) were reported, a unique feature of mpox in Cameroon. The overall case-fatality ratio of 2.2% was associated with clade II. We found mpox occurred only in the forested southern part of the country, and MPXV phylogeographic structure revealed a clear geographic separation among concurrent circulating clades. Clade I originated from eastern regions close to neighboring mpox-endemic countries in Central Africa; clade II was prevalent in western regions close to West Africa. Our findings suggest that MPXV re-emerged after a 30-year lapse and might arise from different viral reservoirs unique to ecosystems in eastern and western rainforests of Cameroon.


Asunto(s)
Monkeypox virus , Mpox , Humanos , Camerún/epidemiología , Monkeypox virus/genética , Ecosistema , Mpox/epidemiología , África Occidental/epidemiología
16.
Emerg Infect Dis ; 30(3): 560-563, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38407162

RESUMEN

Analysis of genome sequencing data from >100,000 genomes of Mycobacterium tuberculosis complex using TB-Annotator software revealed a previously unknown lineage, proposed name L10, in central Africa. Phylogenetic reconstruction suggests L10 could represent a missing link in the evolutionary and geographic migration histories of M. africanum.


Asunto(s)
Evolución Biológica , Mycobacterium , Filogenia , Mycobacterium/genética , Programas Informáticos , África Central/epidemiología
17.
Environ Entomol ; 53(2): 249-258, 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38309712

RESUMEN

Knowledge of insect pest ecology and biology is important for maximizing crop protection and reducing crop losses. Currently, we lack an efficient control program for the cocoa mirid Sahlbergella singularis Haglund (Hemiptera: Miridae), the principal insect pest of cocoa in West and Central Africa. A 2-yr study was conducted in 11 plantations across Ayos and Konye, two of the largest cocoa growing areas of Cameroon. We evaluated the effects of mirid sex pheromone and climatic variations on mirid population dynamics and their associated cocoa damage. Sex pheromone traps caught 1.5-fold higher mirids in Ayos than in Konye, with more overall counts in 2015 than in 2016. Cocoa pod counts were also significantly higher in 2015 than in 2016 and were negatively correlated with temperature and relative humidity. In both localities, mirid populations and associated cocoa pod damage were suppressed in plantations where sex pheromone traps were used. Damage incidence was positively correlated with mirid counts, confirming that the cocoa pod is the preferential site for mirid feeding and reproduction. As such, damage incidence could be used as proxy for comparative mirid population level due to the mirid's cryptic habit. Of the recorded weather variables, only relative humidity was correlated (negatively) with damage severity. Our data on the relationships between damage caused by mirids and their population dynamics and sex pheromone trap catches suggest that an effective control strategy using mass trapping could be developed for mirid management in cocoa plantations.


Asunto(s)
Cacao , Hemípteros , Heterópteros , Atractivos Sexuales , Animales , Feromonas , Camerún , Control de Insectos
18.
Glob Chang Biol ; 30(1): e17154, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38273529

RESUMEN

A large share of the global forest restoration potential is situated in artificial 'unstable' mesic African savannas, which could be restored to higher carbon and biodiversity states if protected from human-induced burning. However, uncertainty on recovery rates in protected unstable savannas impedes science-informed forest restoration initiatives. Here, we quantify the forest restoration success of anthropogenic fire exclusion within an 88-ha mesic artificial savanna patch in the Kongo Central province of the Democratic Republic of the Congo (DR Congo). We found that aboveground carbon recovery after 17 years was on average 11.40 ± 0.85 Mg C ha-1 . Using a statistical model, we found that aboveground carbon stocks take 112 ± 3 years to recover to 90% of aboveground carbon stocks in old-growth forests. Assuming that this recovery trajectory would be representative for all unstable savannas, we estimate that they could have a total carbon uptake potential of 12.13 ± 2.25 Gt C by 2100 across DR Congo, Congo and Angola. Species richness recovered to 33.17% after 17 years, and we predicted a 90% recovery at 54 ± 2 years. In contrast, we predicted that species composition would recover to 90% of old-growth forest composition only after 124 ± 3 years. We conclude that the relatively simple and cost-efficient measure of fire exclusion in artificial savannas is an effective nature-based solution to climate change and biodiversity loss. However, more long-term and in situ monitoring efforts are needed to quantify variation in long-term carbon and diversity recovery pathways. Particular uncertainties are spatial variability in socio-economics and growing conditions as well as the effects of projected climate change.


Asunto(s)
Carbono , Pradera , Humanos , República Democrática del Congo , Carbono/metabolismo , Bosques , Biodiversidad , Árboles/metabolismo , Ecosistema
19.
Malar J ; 23(1): 27, 2024 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-38238806

RESUMEN

BACKGROUND: Though Plasmodium vivax is the second most common malaria species to infect humans, it has not traditionally been considered a major human health concern in central Africa given the high prevalence of the human Duffy-negative phenotype that is believed to prevent infection. Increasing reports of asymptomatic and symptomatic infections in Duffy-negative individuals throughout Africa raise the possibility that P. vivax is evolving to evade host resistance, but there are few parasite samples with genomic data available from this part of the world. METHODS: Whole genome sequencing of one new P. vivax isolate from the Democratic Republic of the Congo (DRC) was performed and used in population genomics analyses to assess how this central African isolate fits into the global context of this species. RESULTS: Plasmodium vivax from DRC is similar to other African populations and is not closely related to the non-human primate parasite P. vivax-like. Evidence is found for a duplication of the gene PvDBP and a single copy of PvDBP2. CONCLUSION: These results suggest an endemic P. vivax population is present in central Africa. Intentional sampling of P. vivax across Africa would further contextualize this sample within African P. vivax diversity and shed light on the mechanisms of infection in Duffy negative individuals. These results are limited by the uncertainty of how representative this single sample is of the larger population of P. vivax in central Africa.


Asunto(s)
Malaria Vivax , Malaria , Animales , Humanos , Plasmodium vivax/genética , Malaria Vivax/parasitología , África Central , Genómica , Sistema del Grupo Sanguíneo Duffy/genética
20.
J Public Health Afr ; 14(9): 2433, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37927361

RESUMEN

The occurrence of epidemics is known to contribute in reducing the capacity of health facilities to deliver care and the predisposition of populations to seek care through several mechanisms. The objective was to assess the effect of the COVID-19 on vaccination coverage of the expanded program of immunization (EPI) vaccines in children aged 0-11 months. The study involved a descriptive and case control designs exhaustively targeting health facilities in health areas from selected health districts. The descriptive part explored the distribution of immunization coverage 12 months before and during COVID-19. Data were extracted from monthly EPI reports of health areas. Cases were months with immunization coverages of Bacille Calmette-Guerin (BCG), Measles Mumps-Rubella 1 (MMR1) or Diphtheria-Pertussis-Tetanus Hepatitis B + Hemophilus influenzae type b dose 3 (DPT-Hi+Hb3) less than 80%. The exposure were months belonging to the pandemic period. Of the 78 targeted health areas, 74 (94.87%) were reached. The monthly immunization coverage of BCG, RR1, DPT-Hi+Hb 1 and 3 decreased during the pandemic period by minimum 30%. Being a health-area month belonging to the COVID-19 pandemic period was found to be significantly associated to lower BCG [OR=2.00 (1.61; 2.50); P#x003C;0.001], MMR1 [OR=2.45 (1.76; 3.41); P#x003C;0.001] and DPT-Hi+Hb3 [OR=2.11 (1.68; 2.640); P#x003C;0.001] immunisation coverage. COVID-19 had a significant effect on the decrease of immunization coverages of antigens offered in the EPI program. This raises the need to develop interventions during health emergencies to prevent disruption of health services access.

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