International Centre of Insect Physiology and Ecology

BackgroundThis study investigated indigenous knowledge-based production practices and utilization of stingless bee honey (SBH) among rural communities in Ethiopia’s humid Afromontane Forest zones of the Southwest (Kaffa, Sheka, Majang, Jimma) and the semi-arid Borena Zone in the South. SBH is an important medicinal, nutritional and cultural resource for these communities, yet information on local production systems, species used, harvest practices and threats are limited.MethodsA cross-sectional survey was conducted among 253 respondents selected from communities identified as potential stingless bee producers and users in the humid Afromontane Forest districts of the Southwest and the semi-arid forest district of southern Ethiopia. Data were collected using a combination of structured interviews and direct field observations to collect comprehensive information on local production practices, species distribution, harvesting techniques, utilization patterns, and the major challenges associated with stingless bee honey (SBH) production.ResultsThe findings show that SBH harvesting is primarily conducted by men (93.3%), with most harvesters also engaged in agriculture and livestock production. Traditional ecological knowledge is predominantly passed down from elders (78.7%). Educational levels vary, with primary education being the most common. The majority of SBH is obtained from wild colonies (97.6%), with limited efforts toward domestication (2.4%). In Yabello, honey is collected from three species: Plebeina armata, Meliponula beccarii, and Hypotrigona species, known locally as “Dama Damu Guracha,” “Dama Damu Dimma,” and “Tunale,” respectively, in the Oromifa language. In the Southwest region (Kaffa, Sheka, Majang, and Jimma), M. beccarii and H. trigona are identified as the primary species, each with distinct local names depending on the zone. Communities in the study area possess traditional knowledge and skills that are primarily focused on digging around colonies to create nesting spaces. However, there are significant seasonal variations in harvesting times across different zones. The peak harvesting periods in Kaffa, Sheka, Majang, and Jimma zones occur in April, while in the Borena Zone, it extends from April to June. Colonies are located by observing and tracking the movement of worker bees. Harvesting techniques differ, with the majority (74.3%) employing squeezing methods, while 21.3% use a combination of squeezing and colony destruction. SBH is mainly harvested once a year, predominantly for medicinal purposes (94.9%). There are notable differences in production volume across regions, with the highest estimated yield from Sheka Zone (4.8 ± 8 kg) over the past 12 months and the lowest from Majang (1.2 ± 1.6 kg). The honey is consumed in various ways, often before meals, for its medicinal properties, such as treating asthma, colds, and respiratory diseases. The study also highlights major threats to meliponine colonies, including predators, land-use changes, unsustainable harvesting practices, and agrochemical use, with 83% of respondents concerned about the potential endangerment of these bees. Despite the longstanding tradition of SBH production, only 1.9% of respondents have received training in meliponiculture.ConclusionIndigenous knowledge of stingless bee honey production remains a vital component of local culture and livelihoods in Ethiopia. However, the practice faces serious challenges due to limited training, lack of modern meliponiculture practices, and environmental pressures. Strengthening conservation efforts, providing technical training, and integrating traditional knowledge with modern practices are essential for sustaining stingless bee populations and promoting the sustainable production of this valuable honey.

The rise of multidrug-resistant (MDR) pathogens and the overharvesting of medicinal plants such as Prunus africana highlight the need for sustainable discovery platforms. In this study, the antimicrobial potential of 23 endophytic bacterial strains isolated from P. africana was evaluated. Stronger activity against Gram-negative than Gram-positive pathogens was observed (p < 0.001). Multivariate analysis identified six endophytic bacterial isolates that exhibited antimicrobial activity against all six tested pathogens. These were Ralstonia pickettii, Bacillus altitudinis, Stenotrophomonas maltophilia, Bacillus paramycoides, Sphingopyxis chilensis, and Virgibacillus halophilus. Gas chromatography-mass spectrometry (GC-MS) profiling of their ethyl acetate extracts revealed 74 metabolites, including terpenoids (e.g., 5-cedranone), phenolic acids (e.g., 4-hydroxybenzoic acid), diketopiperazines, and fatty acids (hexadecanoic, octadecanoic acids). The metabolomes showed biosynthetic congruence with the host plant producing analogous antimicrobial compounds alongside unique metabolites. These findings demonstrate that P. africana endophytes represent a sustainable, cultivable source of antibacterial agents active against Gram-negative pathogens, addressing both drug discovery and conservation needs.

Despite the significant impact of long-lasting insecticidal nets (LLINs) and indoor residual spraying (IRS) on malaria, 597,000deaths from malaria were still recorded in 2023. Additional measures are clearly needed to complement current tools. We assessed the efficacy of insecticide-treated window screens (a piece of PermaNet 3.0 containing deltamethrin + piperonyl butoxide) versus untreated window screening and eave tube inserts treated withβ-cyfluthrin as household interventions againstAnopheles gambiaesensu lato. Between August and October 2022, five experimental houses in Kolongonouan village, central Côte d'Ivoire, were used under semi-field conditions to evaluate the following interventions: (i) standard control house with small openings in the eaves and no window screens (SCH); (ii) insecticide-treated screening (ITS) of windows with small openings in the eaves (ITS op); (iii) ITS of windows with eaves blocked to prevent mosquito entry via eaves (ITS blq); (iv) insecticide treatment applied to the eaves using In2Care eave tubes, without window screening (ET); and (v) untreated window screening together with insecticide-treated eave tubes (SET). The efficacy of these treatments on the indoor and outdoor density of naturally recruiting Anopheles gambiae mosquitoes was assessed by human landing catches from 6:00pm to 8:00am. The impact of these treatments on mosquito mortality and blood-feeding rates was further assessed using release-recapture experiments, in which large enclosures were built around individual houses and approximately 100 non-blood-fed femaleAn. gambiae were released each night over 15 nights. In addition, for the ITS blq treatment, the importance of physical integrity was assessed by evaluating the effect of damaging the screening with two or four 4cm × 4cm holes in each screened window. Insecticide-treated window screening plus eave blocking (ITS blq) significantly reduced by 31.8% the number of An. gambiae entering houses overnight relative to standard control houses (SCH) (P < 0.001). The use of untreated screening + eave tubes (SET) induced a similar reduction (27.0%, P < 0.001). The house entry reduction magnitude for eave tubes alone (ET) was lower (23.5%), though it remained significant relative to the control (P < 0.001). The impact of the ITS op (insecticide-treated window screening with open eaves) was lower and nonsignificant (18.1%; P = 0.4019). There were no significant differences in house entry rates between ET, ITS blq, and ITS op (P > 0.05). The peak in mosquito abundance within houses occurred between 11:00pm and 3:00am. There were no significant differences between treatments in the numbers of mosquitoes collected outdoors. In the release-recapture experiments, all treatments significantly reduced the blood-feeding rate and increased the mortality of An. gambiae, with again a similar impact for ITS blq and SET. Damaging the ITS with two holes still led to a significant reduction in blood-feeding rate, but protection was lost with four holes. Mortality rate also declined with increasing levels of damage, although it remained significantly higher than that with the untreated window screening. This study demonstrated that the combination (insecticide-treated window screening and blocking of eave access) reduced mosquito entry, increased mortality, and lowered blood-feeding rates of An. gambiae to levels comparable to insecticide-treated eave tubes combined with untreated window screening (SET). A previous cluster randomized controlled trial of SET in this area demonstrated a significant reduction in malaria incidence and prevalence. Insecticide-treated window screens could therefore yield a similar epidemiological impact while potentially being simpler and less expensive to implement. Larger-scale epidemiological trials involving communities are needed to test this assumption and further optimize the approach.

Microsporidia MB is an endosymbiotic microbe found in Anopheles mosquito populations. This symbiont can block Plasmodium transmission in mosquitoes, and it can spread through mosquito populations and be sustained over generations by vertical and horizontal transmission. These characteristics make Microsporidia MB a potential candidate for symbiont-based malaria vector control. However, the mechanistic basis of interactions between Microsporidia MB and Anopheles arabiensis is poorly characterized. We investigated how the presence of Microsporidia MB affects transcriptomics profiles and the gut microbiota composition and diversity in non-blood-fed and blood-fed (24-, 48- and 72-hours post blood meal) An. arabiensis mosquitoes. We observed that mosquito infection with Microsporidia MB upregulated farnesoic acid O-methyltransferase, a gene linked to juvenile hormone biosynthesis in the non-blood-fed mosquitoes. In addition, blood feeding in Microsporidia MB positive mosquitoes was associated with an activation of immune-related genes 24h after a blood meal, where several genes including the lipopolysaccharide tumor necrosis factor gene were upregulated. Interestingly, we also observed that Microsporidia MB positivity was associated with a microbiota shift to favor the proliferation of microbes including Pseudomonas and Serratia 24h post blood meal. There were indications of immune system activation in Microsporidia MB positive mosquitoes up to 48h after a blood meal where factors such as the peptidoglycan recognition SC2-like and lysozyme c-1 were upregulated. Notably, an upregulated immune system at this time point was associated with downregulation of genes associated with metabolism and the restoration of Serratia, Pseudomonas and other key microbes to relative abundances similar to those recorded in non-blood-fed mosquitoes. At the 72-hour time point, Microsporidia MB positive mosquitoes exhibited a downregulation of genes associated with immunity, including cecropins and defensins, while metabolic processes were predominantly upregulated. Our results provide insights into the effect of Microsporidia MB infection on the An. arabiensis gene expression and gut microbiota profiles. This work will contribute to mechanistic insights into symbiont-mediated malaria transmission blocking.

<title>Abstract</title> Global biodiversity is declining at unprecedented rates, yet most monitoring indicators remain vertebrate-centric. Here, we introduce an insect-based biodiversity intactness (IBI) indicator, demonstrated across Africa, that integrates large-scale insect occurrence records with Earth Observation data and a pre-human baseline of potential insect diversity. The IBI reveals gradients of ecosystem intactness across all major African agro-ecological zones and detects sensitivity to land-use mosaics such as agroforestry. Unlike vertebrate-based indices, it captures fine-scale ecological variation and reflects the importance of residual vegetation within agro-ecological systems. Block-based cross-validation provides transparent uncertainty estimates, enabling the IBI to scale from local assessments to continental monitoring. Beyond the African case study, the framework is globally transferable, offering a standardized insect-based measure for biodiversity monitoring and policy reporting under the Kunming–Montreal Global Biodiversity Framework.

We study the impact of fall armyworm (FAW) infestation on nutrition security outcomes in eastern Uganda, measuring nutrition security by dietary diversity scores of vulnerable household members--children under 5 years and their mothers. We use different regression models and aim to take the endogeneity of FAW infestation seriously. We also analyse FAW's impact pathway to nutrition status and ask whether impacts are caused by reduced maize yields and sales or increased costs associated with insecticide use. The main results are that high FAW infestation reduces maize yields and sales, and adversely affects dietary diversity.

Abstract For animals living in a noisy world, the volume of potentially relevant information exceeds attentional capacity, but relying on the same cue in multiple contexts might be a solution to this problem. This solution has been suggested by findings from research on Evarcha culicivora, a mosquito-specialist jumping spider in which both sexes rely on red-coloured cues in the context of identifying blood-carrying Anopheles mosquitoes as preferred prey. In a second context, males also attend to the red-coloured faces of other males that are displayed in male–male interactions. Here, as a third context, we present evidence that the presence of a male’s red face is also used as a mate-choice cue for females. In a Y-shaped arena, we gave females the choice between two size-matched stationary male specimens enclosed in glass vials. With colour as the only variable, significantly fewer females chose (i.e. approached and tapped) the vials that housed males with their red facial coloration concealed by application of black liquid eyeliner when the alternative was sham-treated males that had their red facial coloration intact. Our findings suggest that, for E. culicivora, relying on the same colour in three different contexts may function as a way to minimize attentional load.