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Abstract Background In sub-Saharan Africa, understanding of the immune process associated with the COVID-19 pandemic remains scarce. This study aimed to investigate the relationship between plasma neopterin concentrations and COVID-19 infection, focusing on changes over time and age-related changes in immune response. Methods A retrospective case study was conducted during the first wave of COVID-19 from March to August 2020. Whole blood and associated symptoms and comorbidities were collected from patients of all ages and sexes. Concentrations of plasma neopterin were measured using a commercial competitive neopterin ELISA (Neopterin ELISA, IBL International GmbH, Germany). Results We analyzed data for 325 patients: 38% (n = 124) with COVID-19, and 62% (n = 201) without COVID-19, as a control group. We found that plasma neopterin concentrations were significantly higher in the COVID-19 group (mean value 45.1 nmol/L (SD 19)) than in the control group (mean value 33.8 nmol/L (SD 13)) (p = 0.004). In addition, neopterin levels decreased gradually over time in patients with COVID-19 (p

We report the first outbreak of a pathogenic avian influenza virus that occurred on 13 April 2022 in the locality of Meyang, in Gabon, causing the death of 17,498 laying hens. Molecular analysis revealed that the mass mortalities observed in laying hens were associated with serotype H5N1 whose strain belonged to clade 2.3.4.4b. The gabonese Influenza A/H5N1 strains identified showed 99% nucleotide similarity with the Nigerian, Benin and Lesotho strains. The presence of this virus could seriously compromise the development of poultry farming in this country and could threaten public health.

In monotocous mammals, most individuals experience the birth of a younger sibling. This period may induce losses in maternal care and can be physiologically, energetically and emotionally challenging for the older sibling, yet has rarely been studied in wild primates. We used behavioural data collected from a natural population of mandrills to investigate changes in maternal care and mother–juvenile relationship throughout the transition to siblinghood (TTS), by comparing juveniles who recently experienced the birth of a younger sibling, to juveniles who did not. We found that the TTS was associated with an abrupt cessation of the weaning process for the juvenile, and to a decrease in maternal affiliation. Juveniles’ reactions were sex-specific, as males associated less with their mother, while females tended to groom their mother more often after the birth of their sibling. Despite the substantial loss of maternal care, juveniles did not show an increase in conflict or anxiety-related behaviours. This study contributes to explain why short interbirth intervals often pose a risk to juveniles’ survival in monotocous primates. Our results contrast existing studies and further highlight the importance of examining the TTS in species and populations with various life histories and ecologies.

Groundwater is a major resource for drinking water, especially in developing countries, where it is less expensive to treat than surface water. Today, the resource is highly susceptible to pollution, particularly as a result of human activity. This review was based on a literature review and critical analysis of models for estimating the groundwater vulnerability. The results show that the deepest porous aquifers are the least susceptible to pollution, whereas those in karstic and fissured environments are susceptible, whatever their depth. Pollution usually arises from human activity. Critical analysis of the literature shows that existing methods are developed in specific environmental contexts. Given the variability of factors in space and time, these methods do not take the intrinsic realities of all natural settings into account adequately and are not perfectly applicable in all environments. This highlights the need to develop appropriate models for each environment, such as that of the highlands in countries such as Cameroon. HIGHLIGHTS The deepest porous aquifers are less susceptible to pollution than karstic and fissured aquifers.; Existing methods are developed in specific environmental contexts, to solve given problems.; The variability of factors in space and time means that pre-existing methods are not suitably valid in all natural settings.;

Termites are one of the most common pests that damage wood and other cellulosic materials. Although Africa has more varieties of termite species than any other continent, few entomological studies have been conducted in Gabon. Identifying termites poses significant difficulties for entomologists. The aim of this study was to evaluate the reliability and confirm the significance of MALDI-TOF MS in identifying fresh termites collected in equatorial Africa.A total of 108 termites were collected from 13 termite nests during a field mission in 2021 in Lekedi and Bongoville, Gabon. Termites were morphologically identified and subjected to MALDI-TOF MS, then molecular analyses using the COI and 12S rRNA genes.Four termite species were morphologically identified in this study: Pseudacanthotermes militaris, Macrotermes muelleri, Macrotermes nobilis, and Noditermes indoensis. However, when using molecular biology, only three species were identified, namely Macrotermes bellicosus, P. militaris, and N. indoensis, because the specimens initially identified as M. muelleri and M. nobilis were found to be M. bellicosus.The MALDI-TOF MS spectral profiles of the termites were all of good quality, with intra-species reproducibility and inter-species specificity. The spectra of 98 termites were blind tested against our upgraded database, which included the spectra of ten termite specimens. All tested spectra were correctly matched to their respective species, with log score values (LSVs) ranging from 1.649 to 2.592. The mean LSV was 2.215 ± 0.203, and the median was 2.241. However, 95.91% (94/98) of our spectra had LSVs above 1.8. This study demonstrates how a proteomic approach can overcome termites' molecular and morphological identification limitations and serve as a useful taxonomic tool.

Résumé: Depuis toujours, ce thème que nous avons abordé tourmente notre esprit. Ainsi, en raison de l’ambiguïté de ces trois concepts, nous avons essayé de vulgariser l’essentiel de leur quintessence. Tout d’abord, le destin est étudié sous l’angle divin. Pour le dire en d’autres termes, le destin comme une providence, une chose qui émane de Dieu. De plus, il est inéluctable, fatal et inchangeable. Ensuite, la destinée semble être l’opposé du destin. Dans cette partie, nous étions dans l’obligation de constater que certaines personnes tentent à s’insurger contre la volonté divine jusqu’à vouloir changer le cours de leurs vies. Pour d’autres, ils cherchent le succès à tout prix, d’où l’importance de souligner quelques pratiques illicites auxquelles ils s’adonnent. Puis, la grâce. Cette dernière a connu une multitude de façons d’être interprétée : la Grâce de Dieu et celle du diable que nous considérons comme envieuse et éphémère, etc. En fin de compte, les points communs, les ambivalences ainsi que la complémentarité entre ces notions susmentionnées nous ont permis de mettre en lumière les enjeux. En effet, tout au long de cette étude, les productions d’auteurs philosophiques tels que les existentialistes, les essentialistes mais également la bible nous ont servi de tremplin afin de mieux rendre ce texte véhément. Mots-clés : destin ; destinée ; grâce ; convergence ; divergence

Natural coagulants can be an alternative solution to minimise the environmental pollution and health risks caused by the use of chemical coagulants. The main objective of this research was to evaluate the performance of groundnut extract for turbidity removal from water. For this, the active coagulant agents were extracted from the deshelled nuts and used in a series of water treatment tests performed at low, medium, and high turbidity levels using synthetic turbid water. The groundnut extract showed good coagulative abilities, close to those of Al2(SO4)3. The best performance was obtained at medium turbidity (150 NTU), where the extract removed 89% of the turbidity using a 500 mg/L dosage. However, it was not as efficient as Al2(SO4)3, whose coagulation was better at every turbidity level. The use of the groundnut extract does not modify the water's pH significantly and the floc size decreases as turbidity increases, although they are bigger than those produced by Al2(SO4)3. Its flocculation and sedimentation processes are also quick (each less than 10 min) and quicker than those with Al2(SO4)3. Hence, the groundnut extract is a viable alternative to chemical coagulants. HIGHLIGHTS Groundnut extract can be used efficiently to treat water at any turbidity level.; Its application does not modify the pH of water significantly.; The treatment process is quick, less than 15 min.;

The purpose of this work was to show that the change in land use impacts the quality of free groundwater and therefore the health of the population in the city of Bafoussam. Land use was dominated by housing (about 42%) followed by agricultural areas (33%) and green space. The socio-economic diagnosis by the guided survey showed that 62.5% of the population consumes CAMWATER water with malaria as the dominant water-related disease. The collection of water samples analysed by the colorimetric and photometric assay has allowed us to obtain a dominant water facies of the chloride and sulphate–calcium–magnesium type. The mapping of areas potentially vulnerable to pollution by ArcGIS 10.8 software presents the low-lying areas, downstream of agricultural sites, close to industries and neighbourhoods with strong urban disorder as the most vulnerable to pollution and therefore retained as actors of diffuse groundwater pollution in the city of Bafoussam. Thus, the change in land use and the increase in agglomeration degrade the quality of groundwater in this city. HIGHLIGHTS The quality of Bafoussam's groundwater is deteriorating as time goes by.; The growing urbanization of the city of Bafoussam is uncontrolled and anarchic.; The industrial and demographic development influences the quality of groundwater in the city of Bafoussam.; Concentrations of chemical elements exceeding those recommended by the WHO are mainly related to the overall hygiene quality of the population.;

The Human Immunodeficiency Virus/Acquired Immunodeficiency Syndrome (HIV/AIDS) is still one of the main causes of death in sub-Saharan Africa. Antiretroviral therapies (ARTs) have significantly improved the health conditions of people living with HIV/AIDS (PLWHA). Consequently, a significant drop in morbidity and mortality, along with a reduced incidence of opportunistic infections (OIs), has been observed. However, certain atypical and biological profiles emerge in ART patients post-examination. The objective of this study was to identify the risk factors that contributed to the onset of OIs in HIV patients undergoing ART in Gabon. Epidemiological and biological data were obtained from medical records (2017 to 2019) found at the outpatient treatment centre (CTA) of Franceville in Gabon. Samples for blood count, CD4, and viral load analysis at CIRMF were collected from PLWHA suffering from other pathogen-induced conditions. A survey was carried out and data were analysed using Rstudio 4.0.2 and Excel 2007 software. Biological and socio-demographic characteristics were examined concerning OIs through both a univariate analysis via Fisher’s exact tests or chi2 (χ2), and a multivariate analysis via logistic regression. Out of the 300 participants initially selected, 223 were included in the study, including 154 (69.05%) women and 69 (30.95%) men. The mean age was 40 (38.6; 41.85), with individuals ranging from 2 to 77 years old. The study cohort was classified into five age groups (2 to 12, 20 to 29, 30 to 39, 40 to 49, and 50 to 77 years old), among which the groups aged 30 to 39 and 40 to 49 emerged as the largest, comprising 68 (30.5%) and 75 (33.6%) participants, respectively. It was noted that 57.9% of PLWHA had developed OIs and three subgroups were distinguished, with parasitic, viral, and bacterial infections present in 18%, 39.7%, and 55.4% of cases, respectively. There was a correlation between being male and having a low CD4 T-cell count and the onset of OIs. The study revealed a high overall prevalence of OIs, and extending the study to other regions of Gabon would yield a better understanding of the risk factors associated with the onset of these infections.

The work presented here aims to carry out a physical characterisation of soils to understand their hydrodynamic behaviour and estimate the susceptibility of each group of soils to microbiological pollution. The field work associated with the laboratory work consisted of monitoring the hydrodynamic behaviour of previously identified and selected well waters, measuring the permeabilities of the soil samples and analysing the bacteriological parameters of the sampled well waters. At the end of this work, the piezometric data show a dominant SE-NW and ENE-OSW flow direction. The water levels do not vary significantly between the wet and dry seasons. The granulometric analysis of the soils reveals CU>3 showing a spread out granulometry with very low permeabilities of the order of 1.58×10−7 m/s and moderately high permeabilities of the order of 1.86×10−5 m/s. The microbiological data show pollution of human origin with a high bacterial load in the rainy season represented by a maximum of 240 CFU of Escherichia coli exceeding the WHO standards for drinking water. The majority of the polluted samples come from soils developed on granites and basalts, which are the most susceptible to pollution, making the groundwater vulnerable. HIGHLIGHTS Wells on ignimbritic formations are shallow in the rainy season compared to the dry season.; The permeability of soils on granitic formations is of the order of 10−5 m/s, classified as moderately high.; There is microbiological pollution of human origin in the town of Bafoussam.; Soils on granitic and basaltic formations are more susceptible to pollution and therefore make groundwater vulnerable to pollution.;

Background and Aim: Gastrointestinal parasites identified in the wild can negatively affect host fitness, lower performance, and growth. On the other side, sympatric mammals that share habitat and resources may also cross-transmit parasites, which are often zoonotic and can contribute to morbidity and mortality. This study aimed to characterize the diversity of gastrointestinal parasites circulating in mammalian hosts in Moukalaba-Doudou National Park. Materials and Methods: We screened a total of 25 fecal samples collected from nine wild mammalian species, namely, western gorilla (Gorilla gorilla gorilla), chimpanzee (Pan troglodytes), putty-nosed monkey (Cercopithecus nictitans), African forest elephant (Loxodonta cyclotis), African buffalo (Syncerus caffer), blue duiker (Philantomba monticola), bay duiker (Cephalophus dorsalis), and red river hog (Potamochoerus porcus) as well as people working as trackers (Homo sapiens) using direct microscopic observations following a sedimentation technique to concentrate the fecal material. Results: Of the total 25 fecal samples screened, 15 (60%) were positive for parasitic gastrointestinal infection. Based on the morphology of parasite eggs and cysts, we identified a rich diversity of nematodes, protozoans, trematodes, and cestodes, including unidentified strongyles (73%), Oesophagostomum spp. (53%), Ancylostoma spp. (27%), Trichuris spp. (13%), Ascaris spp. (13%), Mammomonogamus spp. (13%), Strongyloides spp. (47%), Balantidium coli (20%), Entamoeba coli (20%), Endolimax nana (6%), Fasciola hepatica (6%), Paramphistomum spp. (13%), and Taenia spp. (6%). Conclusion: All parasites were found at least once in one of the hosts, and most were potentially zoonotic and responsible for several diseases of public health concern. Because of the small sample size, our findings should not be considered conclusive. Nevertheless, they highlight the diversity of gastrointestinal parasites in this area.

Intersexual dominance, which is measured by the probability that members of one sex elicit submission of members of the other sex during agonistic interactions, is often skewed in favor of males. However, even in sexually dimorphic species, several factors may influence intersexual dominance. Here, we use an 8-year dataset to examine the dynamics of intersexual dominance in wild-living mandrills (Mandrillus sphinx). Mandrills exhibit an extreme male-biased sexual size dimorphism but females show pronounced kin-differentiated social relationships and occasionally form coalitions against males. We established intersexual hierarchies across consecutive 6-month time blocks, representing either mating or birth seasons. Although females appeared to outrank 11% of males, they elicited male submission in only 2% of agonistic interactions against males. This discrepancy is likely due to the temporary residency of most males in the exceptionally large mandrill groups, the sexually coercive male mating strategies and the scarce number of agonistic interactions within most dyads, that may limit hierarchical inferences. In a second step, we found that the intersexual hierarchy mixes the intrasexual ones respecting their respective order. Females outranked mostly young and old males during the mating (vs. birth) season and social integration was positively correlated to dominance status in both sexes. In a third step, we found that females win more conflicts against young or old males which are closer to them in the intersexual hierarchy. These results extend our understanding of female-male dominance relationships by indicating that female mandrills occasionally outrank males who are considerably larger than them, and that a combination of demographic and social factors can influence the intersexual hierarchy.

The first detection of canine parvovirus type-2 (CPV-2) was in the early 1970s, when it was known to cause severe gastroenteritis in dogs. However, it has evolved over the years into CPV-2a within 2 years, into CPV-2b after 14 years, into CPV-2c after 16 years and more recently CPV-2a-, 2b- and 2c-like variants reported in 2019, with a global distribution. Reports on the molecular epidemiology of this virus are missing in most African countries. The report of clinical cases among vaccinated dogs in Libreville in Gabon triggered the execution of this study. The objective of this study was to characterize circulating variants from dogs showing clinical signs suggestive of CPV that were examined by a veterinarian. A total of eight (8) fecal swab samples were collected, and all had positive PCR results. Sequencing, Blast analysis and assembly of two whole genomes and eight partial VP2 sequences were performed, and the sequences submitted to GenBank. Genetic characterization revealed the presence of CPV-2a and CPV-2c variants with predominance of the former. Phylogenetically, the Gabonese CPVs formed distinct groups similar to Zambian CPV-2c and Australian CPV-2a sequences. The antigenic variants CPV-2a and CPV-2c have not yet been reported in Central Africa. However, these CPV-2 variants circulate in young, vaccinated dogs in Gabon. These results suggest additional epidemiological and genomic studies are required in order to evaluate the occurrence of different CPV variants in Gabon and effectiveness of the commercial vaccines used against protoparvovirus in the country.

Antrocaryon klaineanum is traditionally used for the treatment of back pain, malaria, female sterility, chlamydiae infections, liver diseases, wounds, and hemorrhoid. This work aimed at investigating the bioactive compounds with antileishmanial and antiplasmodial activities from A. klaineanum. An unreported glucocerebroside antroklaicerebroside (1) together with five known compounds (2–6) were isolated from the root barks of Antrocaryon klaineanum using chromatographic techniques. The NMR, MS, and IR spectroscopic data in association with previous literature were used for the characterization of all the isolated compounds. Compounds 1–4 are reported for the first time from A. klaineanum. The methanol crude extract (AK-MeOH), the n-hexane fraction (AK-Hex), the dichloromethane fraction (AK-DCM), the ethyl acetate fraction (AK-EtOAc), and compounds 1–6 were all evaluated for their antiparasitic effects against Plasmodium falciparum strains susceptible to chloroquine (3D7), resistant to chloroquine (Dd2), and promastigotes of Leishmania donovani (MHOM/SD/62/1S). The AK-Hex, AK-EtOAc, AK-MeOH, and compound 2 were strongly active against Dd2 strain with IC50 ranging from 2.78 ± 0.06 to 9.30 ± 0.29 µg/mL. Particularly, AK-MeOH was the most active—more than the reference drugs used—with an IC50 of 2.78 ± 0.06 µg/mL. The AK-EtOAc as well as all the tested compounds showed strong antileishmanial activities with IC50 ranging from 4.80 ± 0.13 to 9.14 ± 0.96 µg/mL.

Although antibiotic resistance is a major issue for both human and animal health, very few studies have investigated the role of the bacterial host spectrum in its dissemination within natural ecosystems. Here, we assessed the prevalence of methicillin resistance among Staphylococcus aureus (MRSA) isolates from humans, non-human primates (NHPs), micromammals and bats in a primatology center located in southeast Gabon, and evaluated the plausibility of four main predictions regarding the acquisition of antibiotic resistance in this ecosystem. MRSA strain prevalence was much higher in exposed species (i.e., humans and NHPs which receive antibiotic treatment) than in unexposed species (micromammals and bats), and in NHP species living in enclosures than those in captivity—supporting the assumption that antibiotic pressure is a risk factor in the acquisition of MRSA that is reinforced by the irregularity of drug treatment. In the two unexposed groups of species, resistance prevalence was high in the generalist strains that infect humans or NHPs, supporting the hypothesis that MRSA strains diffuse to wild species through interspecific transmission of a generalist strain. Strikingly, the generalist strains that were not found in humans showed a higher proportion of MRSA strains than specialist strains, suggesting that generalist strains present a greater potential for the acquisition of antibiotic resistance than specialist strains. The host spectrum is thus a major component of the issue of antibiotic resistance in ecosystems where humans apply strong antibiotic pressure.

Malaria parasites infect a wide range of vertebrate hosts, such as reptiles, birds and mammals (i.e., primates, ungulates, bats, and rodents). Four Plasmodium species and their subspecies infect African Muridae. Since their discoveries in the 1940s, these rodent Plasmodium species have served as biological models to explore many aspects of the biology of malaria agents and their interactions with their hosts. Despite that, surprisingly, little is known about their ecology, natural history and evolution. Most field studies on these parasites, performed from the 1940s to the early 1980s, showed that all rodent Plasmodium species infect only one main host species, the thicket rat. In the present study, we re-explored the diversity of Plasmodium parasites infecting rodent species living in peridomestic habitats in Gabon, Central Africa. Using molecular approaches, we found that at least two Plasmodium species (Plasmodium vinckei and Plasmodium yoelii) circulated among five rodent species (including the invasive species Mus musculus). This suggests that the host range of these parasites might be larger than previously considered. Our results also showed that the diversity of these parasites could be higher than currently recognized, with the discovery of a new phylogenetic lineage that could represent a new species of rodent Plasmodium. Keywords: Rodent, Malaria, Plasmodium, Central Africa, Mus musculus, Host range

COVID-19 is an emerging respiratory disease; it was declared a global pandemic by the World Health Organization. This survey aimed to describe the knowledge, attitudes, perception and practices of the Gabonese public towards COVID-19. This study was performed on 1016 participants. All participants filled in the questionnaire voluntarily, reporting demographic characteristics and answering questions assessing their level of knowledge, attitudes, perceptions and practice towards COVID-19. Among participants, there were 535 men and 476 women. The mean age of the participants was 33.2 ± 16.7 years old. Almost all participants (98.1%) said that they had heard about COVID-19 but only 2.8% knew the pathogenic agent responsible for COVID-19. More than 80% knew that the disease could be transmitted by greeting infected people (87.3%), kissing an infected person (90.0%), touching an infected doorknob (83.5%) and attending meetings (83.9%). The mean knowledge score was higher among younger than older participants, higher among participants living in urban areas than those living in rural areas and higher among participants with higher levels of education than those with lower levels of education. In general, respondents had good knowledge of COVID-19 and a positive attitude towards using protective measures; however, there were differences according to gender, age group, place of residence, professional group and level of education.

Oesophagostomosis is a zoonotic disease caused by nematodes of the genus Oesophagostomum in the intestinal walls of many species, including ruminants, pigs, humans, and nonhuman primates. Although great apes appear to tolerate the parasite in the wild, they can develop a clinical form that can lead to death in captivity and the natural environment. At the Primatology Centre of the International Centre for Medical Research in Franceville (CIRMF) in Gabon, we recorded 4 deaths of chimpanzees (Pan t. troglodytes) caused by Oesophagostomum spp. between 2015 and 2019. In each case, coprological analysis was positive for strongylid eggs and abdominal ultrasound revealed nodules about 4 cm in diameter on the intestinal and abdominal walls. Albendazole treatments administered by mouth in two doses of 400 mg six months apart resulted in the disappearance of the parasite in coprological samples but the chimpanzees still died. Autopsies carried out on all four chimpanzees revealed a rupture of the cysts and a discharge of pus into the abdomen in each case. We report surgical management involving the removal of Oesophagostomum spp. cysts from a chimpanzee following coprological analysis and abdominal ultrasound examination. Surgical exploration confirmed the fragility of the cystic walls, the rupture of which we avoided. This 5th new case of Oesophagostomum ssp. nodules recovered without complications following the operation and could rejoin his group. We suggest that surgical intervention should be considered in similar cases in captive primates, especially chimpanzees.

There are two independent molecules in the asymmetric unit of the title compound, C16H15NO4, which was isolated from fruits of Zanthoxylum leprieurii. The atoms of the three rings of each molecule are close to coplanar with the largest deviations from the least-squares planes being 0.084 (3) Å and 0.069 (2) Å. Each molecule features an intramolecular O—H...·O hydrogen bond. In the crystal, C—H...·O hydrogen-bonding interactions link the molecules into a three-dimensional network.

Parasites constitute a major selective pressure which has shaped animal behaviour through evolutionary time. One adaption to parasites consists of recognizing and avoiding substrates or cues that indicate their presence. Among substrates harbouring infectious agents, faeces are known to elicit avoidance behaviour in numerous animal species. However, the function and mechanisms of faeces avoidance in non-human primates has been largely overlooked by scientists. In this study, we used an experimental approach to investigate whether aversion to faeces in a foraging context is mediated by visual and olfactory cues in two cercopithecoid primates: mandrills (Mandrillus sphinx) and long-tailed macaques (Macaca fascicularis). Visual and olfactory cues of faeces elicited lower food consumption rates in mandrills and higher food manipulation rates in long-tailed macaques. Both results support the infection-avoidance hypothesis and confirm similar tendencies observed in other primate species. More studies are now needed to investigate the divergence of avoidance strategies observed in non-human primates regarding food contamination.

In this paper present data on the description of rodent species living around human dwelling in some villages of Gabon and their malaria parasites. Rodents are known to colonize various environments, such as forest; domestic or peridomestic environment. They are known to be the hosts of many parasites. Data presented here the circulation of malaria parasites in Gabonese rodents was shown; the estimation of pairwise genetic distances (p-distance) between rodents malaria parasites. We also provide data on rodent species diversity in Gabon. Three hundred and forty-five samples from rodents conserved in biobank of International Center of Medical Researches of Franceville (CIRMF) were used for the study. These samples were collected in six villages of southeastern of Gabon between 2009 and 2016 for routine monitoring of infectious disease. Such data can be used to describe and understanding the evolution and systematics of malaria parasite. This data set support the main findings presented in the research article [1]. Keywords: Molecular tools, Plasmodium, Rodents, Gabon, Cytochrome-b and tissues