Central Africa Research Articles

Clinical and epidemiological features of imported loiasis in Beijing: a report from patients returned from Africa

BackgroundLoiasis is one of the significant filarial diseases for people living in West and Central Africa with wide endemic area but is not seen in China. As economy booms and international traveling increase, China faces more and more imported parasitic diseases that are not endemic locally. Loiasis is one of the parasitic diseases that enter China by travelers infected in Africa. The better understanding of the clinical and laboratory features of loa loa infection will facilitate the diagnosis and treatment of loiasis in China.MethodsThe study targeted travelers who were infected with L. loa in endemic Africa regions and returned to Beijing between 2014 and 2023. Epidemiological, clinical, and biological data as well as treatment of these patients were collected.ResultsTotal 21 cases were identified as L. loa infection based on their typical clinical manifestations and parasite finding. All cases had a history of travel to Africa for more than 6 months, most of them are the construction workers dispatched to West Africa with outdoor activities. Calabar swelling (n = 19; 90.5%) and pruritus (n = 11; 52.4%) were among the most common clinical symptoms followed by muscle pain (n = 7; 33.3%) and skin rash (n = 2; 9.5%). The adult worms were observed in the eyelid or subconjunctiva (n = 2; 9.5%) and subcutaneous tissues (n = 2; 9.5%). Although all patients presented with a high eosinophil count (> 0.52 × 109/L), only two cases displayed microfilariae in fresh venous blood and positive for filarial antigen. A cut section of adult worm was observed through biopsy on a skin nodule surrounded by lymphocytes, plasma cells and eosinophils. All subjects were positive in PCR targeting L. loa ITS-1. The constructed phylogenetic tree based on the amplified ITS-1 sequences identified their genetical relation to the L. Loa from Africa. All patients treated with albendazole and diethylcarbamazine were recovered without relapse.ConclusionThis study provides useful information and guideline for physicians and researchers in non-endemic countries to diagnose and treat loiasis and L. loa infections acquired from endemic regions.

Ex vivo susceptibility to antimalarial drugs and polymorphisms in drug resistance genes of African Plasmodium falciparum, 2016-2023: a genotype-phenotype association study.

Given the altered responses to both artemisinins and lumefantrine in Eastern Africa, monitoring antimalarial drug resistance in all African countries is paramount. We measured the susceptibility to six antimalarials using ex vivo growth inhibition assays (IC50) for a total of 805 Plasmodium falciparum isolates obtained from travelers returning to France (2016-2023), mainly from West and Central Africa. Isolates were sequenced using molecular inversion probes (MIPs) targeting fourteen drug resistance genes across the parasite genome. Ex vivo susceptibility to several drugs has significantly decreased in 2019-2023 versus 2016-2018 parasite samples: lumefantrine (median IC50: 23·0 nM [IQR: 14·4-35·1] in 2019-2023 versus 13·9 nM [8·42-21·7] in 2016-2018, p<0·0001), monodesethylamodiaquine (35·4 [21·2-51·1] versus 20·3 nM [15·4-33·1], p<0·0001), and marginally piperaquine (20·5 [16·5-26·2] versus 18.0 [14·2-22·4] nM, p<0·0001). Only four isolates carried a validated pfkelch13 mutation. Multiple mutations in pfcrt and one in pfmdr1 (N86Y) were significantly associated with altered susceptibility to multiple drugs. The susceptibility to lumefantrine was altered by pfcrt and pfmdr1 mutations in an additive manner, with the wild-type haplotype (pfcrt K76-pfmdr1 N86) exhibiting the least susceptibility. Our study on P. falciparum isolates from West and Central Africa indicates a low prevalence of molecular markers of artemisinin resistance but a significant decrease in susceptibility to the partner drugs that have been the most widely used since a decade -lumefantrine and amodiaquine. These phenotypic changes likely mark parasite adaptation to sustained drug pressure and call for intensifying the monitoring of antimalarial drug resistance in Africa. This work was supported by the French Ministry of Health (grant to the French National Malaria Reference Center) and by the Agence Nationale de la Recherche (ANR-17-CE15-0013-03 to JC). JAB was supported by NIH R01AI139520. JR postdoctoral fellowship was funded by Institut de Recherche pour le Développement.

Ex vivo susceptibility to antimalarial drugs and polymorphisms in drug resistance genes of African Plasmodium falciparum, 2016-2023: a genotype-phenotype association study.

Background: Given the altered responses to both artemisinins and lumefantrine in Eastern Africa, monitoring antimalarial drug resistance in all African countries is paramount. Methods: We measured the susceptibility to six antimalarials using ex vivo growth inhibition assays (IC 50 ) for a total of 805 Plasmodium falciparum isolates obtained from travelers returning to France (2016-2023), mainly from West and Central Africa. Isolates were sequenced using molecular inversion probes (MIPs) targeting fourteen drug resistance genes across the parasite genome. Findings: Ex vivo susceptibility to several drugs has significantly decreased in 2019-2023 versus 2016-2018 parasite samples: lumefantrine (median IC 50 : 23·0 nM [IQR: 14·4-35·1] in 2019-2023 versus 13·9 nM [8·42-21·7] in 2016-2018, p<0·0001), monodesethylamodiaquine (35·4 [21·2-51·1] versus 20·3 nM [15·4-33·1], p<0·0001), and marginally piperaquine (20·5 [16·5-26·2] versus 18.0 [14·2-22·4] nM, p<0·0001). Only four isolates carried a validated pfkelch13 mutation. Multiple mutations in pfcrt and one in pfmdr1 (N86Y) were significantly associated with altered susceptibility to multiple drugs. The susceptibility to lumefantrine was altered by pfcrt and pfmdr1 mutations in an additive manner, with the wild-type haplotype ( pfcrt K76- pfmdr1 N86) exhibiting the least susceptibility. Interpretation: Our study on P. falciparum isolates from West and Central Africa indicates a low prevalence of molecular markers of artemisinin resistance but a significant decrease in susceptibility to the partner drugs that have been the most widely used since a decade -lumefantrine and amodiaquine. These phenotypic changes likely mark parasite adaptation to sustained drug pressure and call for intensifying the monitoring of antimalarial drug resistance in Africa.

An overview of artemisinin-resistant malaria and associated Pfk13 gene mutations in Central Africa.

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.

Study on the change of global ecological distribution of Nicotiana tabacum L. based on MaxEnt model.

Nicotiana tabacum L. (tobacco) has extremely high economic value, medicinal value, scientific research value and some other uses. Though it has been widely cultivated throughout the world, classification and change of its suitable habitats is not that clear, especially in the context of global warming. In order to achieve rational cultivation and sustainable development of tobacco, current (average from 1970-2000) and future (2070, average from 2061-2080) potential suitable habitats of Nicotiana tabacum L. were forecasted with MaxEnt model and ArcGIS platform based on 854 occurrence data and 22 environmental factors in this study. The results revealed that mean temperature of warmest quarter (bio10), annual precipitation (bio12), solar radiation in September (Srad9), and clay content (CLAY) were the four decisive environment variables for the distribution of Nicotiana tabacum L. Under current climate conditions, suitable habitats of Nicotiana tabacum L. were mainly distributed in south-central Europe, south-central North America, most parts of South America, central Africa, south and southeast Asia, and southeast coast of Australia, and only 13.7% of these areas were highly suitable. By the year 2070, suitable habitats under SSP1-2.6, SSP3-7.0, and SSP5-8.5 climate scenarios would all increase with the largest increase found under SSP3-7.0 scenario, while suitable habitats would reduce under SSP2-4.5 climate scenario. Globally, the center of mass of suitable habitats would migrate to southeast to varying degrees within Libya under four different climate scenarios. The emergence of new habitats and the disappearance of old habitats would all occur simultaneously under each climate scenario, and the specific changes in each area, combined with the prediction results under current climate conditions, will provide an important reference for the adjustment of agronomic practices and rational cultivation of Nicotiana tabacum L. both currently and in the future.

HIV incidence among women engaging in sex work in sub-Saharan Africa: a systematic review and meta-analysis

Women who engage in sex work in sub-Saharan Africa have a high risk of acquiring HIV infection. HIV incidence has declined among all women in sub-Saharan Africa, but trends among women who engage in sex work are poorly characterised. We synthesised data on HIV incidence among women who engage in sex work in sub-Saharan Africa and compared these with the total female population to understand relative incidence and trends over time. We searched MEDLINE, Embase, Global Health, and Google Scholar from Jan 1, 1990, to Feb 28, 2024, and grey literature for studies that reported empirical estimates of HIV incidence among women who engage in sex work in any sub-Saharan Africa country. We calculated incidence rate ratios (IRRs) compared with total female population incidence estimates matched for age, district, and year, did a meta-analysis of IRRs, and used a continuous mixed-effects model to estimate changes in IRR over time. From 32 studies done between 1985 and 2020, 2194 new HIV infections were observed among women who engage in sex work over 51 490 person-years. Median HIV incidence was 4·3 per 100 person years (IQR 2·8-7·0 per 100 person-years). Incidence among women who engage in sex work was eight times higher than matched total population women (IRR 7·8 [95% CI 5·1-11·8]), with larger relative difference in western and central Africa (19·9 [9·6-41·0]) than in eastern and southern Africa (4·9 [3·4-7·1]). There was no evidence that IRRs changed over time (IRR per 5 years: 0·9 [0·7-1·2]). Across sub-Saharan Africa, HIV incidence among women who engage in sex work remains disproportionately high compared with the total female population. However, constant relative incidence over time indicates HIV incidence among women who engage in sex work has declined at a similar rate. Location-specific data for women who engage in sex work incidence are sparse, but improved surveillance and standardisation of incidence measurement approaches could fill these gaps. Sustained and enhanced HIV prevention for women who engage in sex work is crucial to address continuing inequalities and ensure declines in new HIV infections. Bill & Melinda Gates Foundation, UK Research and Innovation, National Institutes of Health. For the French translation of the abstract see Supplementary Materials section.

Prevalence and severity of depression and anxiety in infertile female patients attending an academic hospital in central South Africa

Background. Infertility has an incidence of 15 - 20% in South Africa (SA). It may lead to the development of psychological disorders such as anxiety and depression. Objective. To determine the prevalence of depression and anxiety among infertile women attending the Infertility Clinic at a tertiary hospital in central SA. Methods. In this prospective analytic cross-sectional study, information captured included sociodemographic variables such as age, employment status, type and duration of infertility, marital status, type of marriage and education level. The Patient Health Questionnaire-9 (PHQ-9) and the Generalized Anxiety Disorder-7 (GAD-7) test were used to screen for depression and anxiety, respectively.Results. In total, 100 of 108 infertile women completed all the questionnaires correctly. Forty-two (42.0%) of the patients were &gt;35 years and 58.0% were married, with five (8.6%) being in a polygamous marriage. Fifty-three (53.0%) women had never been pregnant before. The prevalence of depression was 53.0%, with 45.0% of these patients showing moderate to moderately severe levels of depression. The level of education was significantly associated with depression (p&lt;0.025). Half of the participants (50.0%) screened positive for anxiety, with 12 (24.0%) having severe anxiety. In total, 40.0% of the participants screened positive for both anxiety and depression. No statistically significant association was observed between depression or anxiety and age, duration of infertility, marital status and employment status. Conclusions. Depression and anxiety disorders are common and often underdiagnosed in women undergoing infertility treatment. Practitioners should screen for these conditions at the initial patient presentation and refer patients for psychological support.

Growing Importance of Camel Milk in Human Health

Milk is considered as a complete food as it is rich in proteins, fats, minerals, and vitamins that are essential for human nutrition. Camel milk, a dietary staple in hot and arid regions for millennia, has recently gained attention for its nutritional richness and therapeutic properties. With a global camel population of 35 million, countries in East and Central Africa harbor the largest populations, with Ethiopia ranking second in production after Somalia. Beyond its significance in pastoralist communities, camel milk exhibits diverse health benefits, including anti-aging, anti-inflammatory, and immunomodulatory effects. Its unique chemical composition, including high levels of vitamin C, essential minerals, and protective proteins like lactoferrin, lactoperoxidase, immunoglobulins, and lysozyme, makes it a potential alternative to bovine milk. Camel milk lacks β-lactoglobulin, which causes allergic to cow milk proteins. Notably, camel milk's role in managing conditions such as diabetes, allergies, autism, cancer, tuberculosis, hepatitis, and arthritis. Moreover, its hypoallergenic nature and antimicrobial properties make it a promising functional food. Insulin-like proteins, which imitate insulin's role in controlling blood sugar levels and hence improve glucose uptake, contribute to its efficacy. Camel milk has cosmetic effects due to the presence of α-hydroxy acids, which help to plump the skin and smooth fine lines. Despite its importance, camel milk remains underappreciated, necessitating further research and awareness efforts to unlock its full therapeutic potential and promote its consumption. This paper aims to shed light on the diverse health benefits of camel milk.

Genetic surveillance reveals low, sustained malaria transmission with clonal replacement in Sao Tome and Principe.

Despite efforts to eliminate malaria in Sao Tome and Principe (STP), cases have recently increased. Understanding residual transmission structure is crucial for developing effective elimination strategies. This study collected surveillance data and generated amplicon sequencing data from 980 samples between 2010 and 2016 to examine the genetic structure of the parasite population. The mean multiplicity of infection (MOI) was 1.3, with 11% polyclonal infections, indicating low transmission intensity. Temporal trends of these genetic metrics did not align with incidence rates, suggesting that changes in genetic metrics may not straightforwardly reflect changes in transmission intensity, particularly in low transmission settings where genetic drift and importation have a substantial impact. While 88% of samples were genetically linked, continuous turnover in genetic clusters and changes in drug-resistance haplotypes were observed. Principal component analysis revealed some STP samples were genetically similar to those from Central and West Africa, indicating possible importation. These findings highlight the need to prioritize several interventions such as targeted interventions against transmission hotspots, reactive case detection, and strategies to reduce the introduction of new parasites into this island nation as it approaches elimination. This study also serves as a case study for implementing genetic surveillance in a low transmission setting.

Challenges towards an AIDS-free generation in Africa and Asia.

To review the latest data on prevention of HIV vertical transmission in Asia and Africa and discuss strategic directions to achieve an AIDS free generation by 2030. Progress in vertical transmission elimination efforts in Africa and Asia have stalled in the last decade, with 130 000 new infections in 2022. Main causes of vertical transmissions vary; in Asia-Pacific due to its low-burden, thus low testing coverage, but high overall vertical transmission rates, in South and East Africa due to new HIV infections during pregnancy and breast/chestfeeding, whereas in Western and Central Africa due to low antiretroviral therapy (ART) coverage. Long-acting injectable ART and neutralizing antibodies for treatment and prevention show promise in supporting efforts to further reduce vertical transmissions. Integrated and more accessible pre- and postnatal care is needed to achieve an AIDS-free generation. Much can be implemented to address existing HIV service gaps; including strengthening of HIV prevention services for youth and women of childbearing age and pregnant people, early detection and treatment, and the delivery of integrated services that can reach and retain pregnant and postpartum people living with HIV in care.

Variability in flood frequency in sub-Saharan Africa: The role of large-scale climate modes of variability and their future impacts

Sub-Saharan Africa (SSA) is strongly affected by flood hazards, endangering human lives and economic stability. However, the role of internal climate modes of variability in driving fluctuations in SSA flood occurrence remains poorly documented and understood. To address this gap, we quantify the relative and combined contribution of large-scale climate drivers to seasonal and regional flood occurrence using a new 65-year daily streamflow dataset, sea-surface temperatures derived from observations, and 12 Single Model Initial-condition Large Ensembles (SMILEs) from the Coupled Model Intercomparison Project Phases 5 and 6. We find significant relationships between floods and large-scale climate variability across SSA, with climatic drivers accounting for 30–90 % of the variability in floods. Notably, western, central, and the summer-rain region of southern Africa display stronger teleconnections to large-scale climate variability in comparison to East Africa and the winter-rain region of South Africa, where regional circulation patterns and human activities may play a more important role. In southern and eastern Africa, floods are mainly influenced by teleconnections with the Pacific and Indian Oceans, while in western and central Africa, teleconnections with the Atlantic Ocean and Mediterranean Sea play a larger role. We also find that the number of floods is projected to fluctuate by ± 10–50 % during the 21st century in response to different sequences of key modes of climate variability. We also note that the relative contributions of large-scale climate variability to future flood risks are generally consistent across all SMILEs. Our findings thus provide valuable information for long-term disaster risk reduction and management.

High Rates of Miscarriage and Stillbirth among Pregnant Women with Clade I Mpox (Monkeypox) Are Confirmed during 2023-2024 DR Congo Outbreak in South Kivu Province.

Mpox (monkeypox) is a neglected tropical disease that has received increased attention since the multi-nation outbreak that began in 2022. The virus is endemic in West and Central Africa, where the Democratic Republic of the Congo (DRC) is the most affected country. Clade I monkeypox virus (MPXV) infection is endemic in the DRC and has an overall case fatality rate of 10.6% among children and adults. A study conducted in Sankuru Province, DRC, from 2007 to 2011 demonstrated that 75% of pregnant women with mpox had miscarriages or stillbirth. Further analysis of a stillborn fetus showed that MPXV could infect both the placenta and fetus, causing congenital infection. No additional cases of Clade I MPXV in pregnant women were reported until a new outbreak occurred in South Kivu Province during 2023 and 2024. Eight pregnant women having Clade I MPXV infection were identified, of whom four had either miscarriages or stillbirth, representing a 50% fetal mortality rate. These reports confirm previous data from the DRC that indicate the capability of Clade I MPXV to affect the fetus, causing congenital infection and fetal loss in a high percentage of cases. In this article, we review both past and new data from the DRC on the effects of Clade I MPXV during pregnancy and discuss the association of mpox with fetal loss.

Solar irrigation potential in Sub-Saharan Africa: a crop-specific techno-economic analysis

In this study, we introduce an integrated modeling framework that combines a hydrologic model, a biophysical crop model, and a techno-economic model to assess solar irrigation potential in Sub-Saharan Africa (SSA) based on seven commonly grown food crops-maize, wheat, sorghum, potato, cassava, tomato, and onion. The study involves determining the irrigation requirements, location-specific capital investment costs, crop-specific profitability, and the cropland area under various cost scenarios (low and high) and soil fertility (low, moderate, near-optimal, and optimal) scenarios. Our research reveals considerable potential for solar irrigation, with profitability and viable cropland areas that vary according to crop type, irrigation system cost scenarios, and soil fertility levels. Our assessment shows that approximately 9.34 million ha of SSA’s current rainfed cropland are hydrologically and economically feasible for solar irrigation. Specifically, maize and onion display the lowest and highest viability, spanning 1–4 million ha and 29–33 million ha, respectively, under optimal soil fertility conditions. In terms of profitability, maize and onion rank as the least and most economically viable crops for solar irrigation, yielding average annual returns of $50-$125/ha and $933-$1450/ha, respectively, under optimal soil fertility conditions. The lower and upper bounds of profitability and cropland range correspond to high-cost and low-cost scenarios, respectively. Furthermore, our study reveals distinct regional differences in the economic feasibility of solar irrigation. Eastern Africa is more economically favorable for maize, sorghum, tomato, and cassava. Central Africa stands out for onion cultivation, whereas West and Southern Africa are more profitable for potato and wheat, respectively. To realize the irrigation benefits highlighted, an energy input of 940-2,168 kWh/ha/yr is necessary, varying by crop and geographic sub-region of the SSA sub-continent. Our model and its results highlights the importance of selecting the right crops, applying fertilizers at the appropriate rates, and considering regional factors to maximize the benefits of solar irrigation in SSA. These insights are crucial for strategic planning and investment in the region’s agricultural sector.

Prevalence and Modes of Transmission of Hepatitis C Virus Infection: A Historical Worldwide Review.

Hepatitis C virus infection affects over 58 million individuals and is responsible for 290,000 annual deaths. The infection spread in the past via blood transfusion and iatrogenic transmission due to the use of non-sterilized glass syringes mostly in developing countries (Cameroon, Central Africa Republic, Egypt) but even in Italy. High-income countries have achieved successful results in preventing certain modes of transmission, particularly in ensuring the safety of blood and blood products, and to a lesser extent, reducing iatrogenic exposure. Conversely, in low-income countries, unscreened blood transfusions and non-sterile injection practices continue to play major roles, highlighting the stark inequalities between these regions. Currently, injection drug use is a major worldwide risk factor, with a growing trend even in low- and middle-income countries (LMICs). Emerging high-risk groups include men who have sex with men (MSM), individuals exposed to tattoo practices, and newborns of HCV-infected pregnant women. The World Health Organization (WHO) has proposed direct-acting antiviral (DAA) therapy as a tool to eliminate infection by interrupting viral transmission from infected to susceptible individuals. However, the feasibility of this ambitious and overly optimistic program generates concern about the need for universal screening, diagnosis, linkage to care, and access to affordable DAA regimens. These goals are very hard to reach, especially in LMICs, due to the cost and availability of drugs, as well as the logistical complexities involved. Globally, only a small proportion of individuals infected with HCV have been tested, and an even smaller fraction of those have initiated DAA therapy. The absence of an effective vaccine is a major barrier to controlling HCV infection. Without a vaccine, the WHO project may remain merely an illusion.

Correction: Response of regional circulation features to the Indian Ocean dipole and influence on Central Africa climate

Correction: Response of regional circulation features to the Indian Ocean dipole and influence on Central Africa climate

Species and Speciation in the Termite-Cultivated Fungus Termitomyces

Termitomyces is a genus of basidiomycete fungi cultivated by termites of the subfamily Macrotermitinae. This symbiosis originated in central Africa, and subsequently, the fungus-growing termites have colonized almost the entire African continent including Madagascar as well as significant parts of Asia. Around 40 species of Termitomyces have been described based on morphology of the sexual fruit bodies, which are associated with some 330 species of fungus-growing termites distributed over 11 genera. However, the total number of fungal species may be higher as not all species regularly produce mushrooms, and morphological variation does not seem to be a reliable criterion for species delimitation in this group. In this study we estimated the total number of species based on ITS-barcode criteria and assessed host specificity and geographic differentiation to infer patterns of speciation. We estimated the total number of phylogenetic species using two methods of DNA sequence-based species delimitation; Automatic Barcode Gap Discovery (ABGD) and the Generalized Mixed Yule Coalescent (GMYC) model on a large dataset of over 1,500 ITS sequences from laboratory cultures, fungarium specimens and the public database NCBI Genbank. This resulted in an estimated 87 species hypotheses using ABGD and 94 species hypotheses using the GMYC model. A phylogenetic reconstruction was performed on representative sequences of the 87 species hypotheses identified by ABGD (the most conservative estimate) constrained by a well-supported phylogeny based on whole-genome data to address host specificity and geographical differentiation. Five main clades were recovered which generally were associated with species of one or two host genera, except for samples collected from the genera Microtermes and Ancistrotermes, which formed two separate non-sister clades. We did not find any evidence for long-term host fidelity as would be expected for species with strict uniparental vertical symbiont transmission. We found strict geographic separation between African and Asian species of Termitomyces and infer a minimum of seven inter-continental migrations. We show that epigeous fruiting of the T. microcarpus group has a single evolutionary origin in Africa and that fruiting in species of this group likely is induced by the fungus rather than by the host-termite species. In contrast, fruiting in the symbionts of some species of Microtermes and Macrotermes may be suppressed by the host-termite species, since mushrooms of certain fungal species are found when those species are associated with some termite-host genera, but never when associated with other host genera. We discuss some examples of incongruence between morphological and phylogenetic species concepts and give suggestions to improve the taxonomy of the genus Termitomyces.

Projected changes in population exposure to extreme precipitation events over Central Africa under the global warming levels of 1.5 °C and 2 °C: insights from CMIP6 simulations

Projected changes in population exposure to extreme precipitation events over Central Africa under the global warming levels of 1.5 °C and 2 °C: insights from CMIP6 simulations

Potato Breeding for Late Blight Resistance in Central and East Africa

Potato late blight is a disease of great loss, which can go beyond 75% in Central and Eastern Africa. With this in mind, in order to limit the excessive use of synthetic fungicides, the use of resistant varieties is a better alternative. This study focuses on the synthesis of works already carried out in the improvement of potato resistance to late blight in Central and East Africa in order to have a general overview. For this purpose, 76 documents were consulted, including 67 scientific articles, eight books, and a web page. The literature has shown that the improvement of potato resistance to late blight in these areas is mainly based on conventional methods throughout the breeding scheme. These studies are mainly led by the International Potato Center. This review covers yield losses due to late blight, the biology of Phytophthora infestans, late blight management methods, the genetics of late blight resistance, genetic resources for late blight resistance in Central and East Africa, screening methods and breeding approaches for potato late blight resistance.

A plea for urgent action: Addressing the critical shortage of cardiothoracic surgical workforce in the COSECSA region.

The College of Surgeons of East, Central, and Southern Africa (COSECSA) comprises 14 countries, many of which currently grapple with an increasing burden of cardiothoracic surgical (CTS) diseases. Health and economic implications of unaddressed CTS conditions are profound and require a robust regional response. This study aimed to define the status of CTS specialist training in the region (including the density of specialists, facilities, and active training posts), examine implications, and proffer recommendations. A desk review of COSECSA secretariat documents and program accreditation records triangulated with information from surgical societies was performed in May 2022 and September 2023 as part of education quality improvement. A modified nominal group process involving contextual experts was used to develop a relevant action framework. Only 6 of 14 (43%) of COSECSA countries offered active training programs with annual intake of only 18 trainees. Significant training gaps existed in Burundi, Botswana, Malawi, Rwanda, South Sudan, Zambia, and Zimbabwe. Country specialist density ranged from 1 per 400,000 (Namibia) to 1 per 8,000,000 (Ethiopia). Overall, the region had 0.2 CTS specialists per million population as compared with 7.15 surgeons per million in High-Income Countries. Surgical education experts proposed an action framework to address the training crisis including increasing investments in CTS education, establishing regional centers of excellence, retention incentives and opportunities for women, and leveraging international partnerships. Proactive investments in infrastructure, human resources, training, and collaborative efforts by national governments, regional intergovernmental organizations, and international partners are critical to expanding regional CTS training.

40 years of forest dynamics and tree demography in an intact tropical forest at M’Baïki in central Africa

A vast silvicultural experiment was set up in 1982 nearby the town of M’Baïki in the Central African Republic to monitor the recovery of tropical forests after disturbance. The M’Baïki experiment consists of ten 4-ha Permanent Sample Plots (PSPs) that were assigned to three silvicultural treatments in 1986 according to a random block design. In each plot, all trees with a girth at breast height greater than 30 cm were spatially located, numbered, measured, and determined botanically. Girth, mortality and newly recruited trees, were monitored almost annually over the 1982–2022 period with inventory campaigns for 35 years. The data were earlier used to fit growth and population models, to study the species composition dynamics, and the effect of silvicultural treatments on tree diversity and aboveground biomass. Here, we present new information on the forest stand structure dynamics and tree demography. The data released from this paper cover the three control plots and constitute a major contribution for further studies about the biodiversity of intact tropical forests.