South Cameroon Research Articles

Archean tectonics in the sangmelima granite-greenstone terrains, Ntem Complex (NW Congo craton), southern Cameroon.

Structural study of in the Sangmelima granite-greenstone terrains (SGB) provide a new overview of the evolution of the Ntem Complex (South Cameroon), the northwestern part of the Congo Craton. The regional deformation is marked by a strong steep dips foliation and steeply plunging mineral-stretching. D1-related structures are folding and shearing by a D2 deformation that is synchronous with extraction granitic dykes. D1–D2 structures were developed during regional E-W sub-horizontal shortening under ductile conditions associated with steeply dipping principal stretching in a transpressive regime, progressive strain localization along strike-slip shear zones. Syn-D1 mineral assemblages and high strain microstructures suggest that ductile deformation D1 occurred under high-grade metamorphic conditions, whereas D2 microstructures suggest a brittle deformation. The strain patterns in the SGB recorded a long-lasting Archean tectonic history within the Archean Ntem Complex (ca. 2.83–2.72Ga). Finally, some Archean structures were reactivated during a brittle deformation (D3), likely during the Eburnean event.

English

Ecotourism is often perceived as a strategy for sustainable biodiversity conservation for protected areas. In Cameroon, there is dearth of information on the impacts of ecotourism on biodiversity conservation of protected areas. The main thrust of this study is to examine local population's perceptions of the impact of ecotourism on biodiversity conservation in and around the Campo Ma'an National Park (CMNP). Data were collected from both primary and secondary sources. Primary data were gotten from household survey (N=124), focus group discussions (N=8) and key informant interviews (N=16). From the findings, 44.4% of the local population perceived ecotourism activities contributing to biodiversity conservation of CMNP against 55.6% with contrary views. Spearman rank correlation coefficients and Chi-square test statistics indicated that, variables plausibly influencing local population's perception of ecotourism impact on biodiversity conservation in and around CMNP were age (p<0.10), gender (p<0.50), main occupation (p<0.10), secondary occupation (p<0.10), time spent in the community (p<0.50), and number of children (p<0.50). From the logistic regression model, the main variables affecting the local population's perception were age, gender and time spent in the community. This study recommends the development of ecotourism friendly policies that can accelerate Public Private Partnership for a participatory and sustainable ecotourism approach for biodiversity conservation and livelihood enhancement in and around the CMNP. It also recommends the development of a gender sensitive ecotourism that will fair opportunities for rural women to benefit from ecotourism activities.   Key words: Ecotourism, biodiversity conservation, perception, adjacent population, national parks, Campo Ma'an National Park, South Cameroon.

Four new genera of Schizopteridae (Hemiptera: Heteroptera) from the Afrotropical and Neotropical regions.

Despite a recent surge of taxonomic work on the dipsocoromorphan family Schizopteridae, new genus-level taxa remain to be documented and described. The curation of Malaise and Yellow Pan Trap sample residues from Central and South America and Cameroon resulted in the discovery of five undescribed species that based on combined molecular and morphological phylogenetic analyses represent four phylogenetically isolated lineages within non-hypselosomatine Schizopteridae. To accommodate these new species, we here describe the four new genera Caucanannus gen. n. (Colombia, Ecuador, and Brazil) with Caucanannus perplexus sp. n. and Caucanannus novissimis sp. n.; Kamakonocoris gen. n. (Cameroon) with Kamakonocoris carinata sp. n.; Perittonannus gen. n. (Costa Rica) with Perittonannus antiquus sp. n.; and Rimanannus gen. n. (Cameroon) with Rimanannus camerunensis sp. n. The four genera are characterized by distinctive wing venation and male and female genitalic features. We provide habitus photographs and document morphological details using digital macrophotography as well as light compound microscopic and scanning electron microscopic images. Maps and measurements are also included.

Ratios and determinants of maternal mortality: a comparison of geographic differences in the northern and southern regions of Cameroon

BackgroundWhile maternal mortality has declined worldwide in the past 25 years, this is not the case for Cameroon. Since there is a predominantly young population in this country, high maternal mortality ratios may persist. Maternal mortality ratios vary within countries, yet it is unknown if the North and South, the most distinct parts of Cameroon, differ in terms of ratios and determinants of maternal mortality.MethodsThis study explored ratios and determinants of maternal mortality in women of childbearing age (15–49 years) and assessed differences between the North and South. We used the Cameroon Demographic and Health Surveys (2004 and 2011) to extract a sample of 18,665 living or deceased women who had given birth. Multivariable logistic regression was used to explore the relationship between maternal mortality and sociocultural, economic and healthcare factors.ResultsMaternal mortality ratios were different for the two regions and increased in the North in 2011 compared to 2004. In the North, any level of education and being Muslim were protective against maternal mortality. Meanwhile, the odds of maternal mortality decreased with increasing age, and having secondary or higher education in the South. Domestic violence and ethnicity were associated with maternal death in the South. Increasing parity was protective of maternal death in both the North and South.ConclusionsMaternal mortality ratios and determinants varied between women of childbearing age in the North and South of Cameroon. These reinforce recommendations for region specific strategies that will improve health communication, community education programs, curb domestic violence and train more community health workers to connect pregnant women with the health system. Programs to reduce maternal death among women with low parity and little or no education should be national priority.

International Cooperation in the Fight against Infectious Diseases: a Case for Legal Epidemiology in Kenya

As of May 21, more than 323,256 people worldwide have died and counting of COVID-19, the highly infectious respiratory disease caused by the coronavirus. The number of people, who have tested positive for COVID-19, has exceeded 4.9 million and counting, according to data compiled by the World Health Organization (WHO).The coronavirus disease 2019 (COVID-19) outbreak in the WHO African Region has rapidly evolved over the past few weeks, as reflected by the significant upsurge in the number of cases, and the rapid geographical expansion of the disease. Since the last situation report by the Johns Hopkins University on 18 March 2020 (External Situation Report 3), 11 new countries in the WHO African Region including Angola, Cape Verde, Chad, Eritrea, Niger, Madagascar, Mali, Mauritius, Mozambique, Uganda, and Zimbabwe have confirmed 1 371 and counting COVID-19 cases. As of 25 March 2020, a cumulative total of 1 716 confirmed cases have been reported across 38 countries in the region, bringing the total number of reported deaths to 30, which corresponds to a case fatality ratio of 1.8% among reported confirmed cases.The most affected countries in the WHO African Region are: South Africa (5647 cases and counting), Algeria (4006 cases and counting), Burkina Faso (645 cases and counting), Senegal (933 cases and counting), Cameroon (1832 cases and counting), and Cote d’Ivoire (1275 and counting) [13].This paper seeks to lay a theoretical foundation for a broader intellectual discourse on the emerging challenges presented by pandemics while discussing and examining how law as a social determinant of health and a factor in the cause, distribution and prevention of disease and injury in populations within Africa and Kenya in particular can be utilized in understanding trends in health laws, study the impact and effectiveness of laws in health, informing and supporting best practices and developing an evidence base of what works in the prevention of infectious diseases and in particular COVID – 19 in Africa (Kenya).

Environmental Sanitation Factors and human Behaviour Associated with Intestinal Parasitic Infections in Rural Communities of Cameroon

Introduction: Intestinal parasitic infections still constitute major public health threats in many areas in Cameroon. To improve control measures, epidemiological data from environmental and human aspects are necessary to draw concrete control strategies to better follow-up the population at risk.
 Aim of the Study: This study aimed to investigate environmental risk factors related to infections in the Lolodorf health district, a high risk area of south Cameroon.
 Methods: A total of 325 participants who gave their informed consent were recruited for the study. Stool samples were collected and examined microscopically in search of helminth eggs and protozoan cysts using the Kato Katz and concentration Formol-ether techniques. Questionnaires were filled by participants to evaluate the risk factors.
 Results: Overall, 117 (42.9%) among the 325 participants harbored at least one parasite species with 75 (27.5%) having single infections and 42 (15.4%) having multiple infections. Ascaris lumbricoides (11.0%), Trichuris trichiura (26.4%), Hookworms (12.5%), Entamoeba coli (10.6%) and Entamoeba histolytica / Entamoeba dispar (1,5%) were diagnosed. Females were more infected (48.7%; p=0.04) compared to males (35.2%). Infection rate varied significantly according to villages (p=0.001). Univariate analysis revealed the following: gender (48.7%; p= 0.04), agricultural activities (47.7%; p= 0.04) and absence of treatment (50.8%: p=0.02) to be risk factors correlated to infection. Other factors such as age (49.3%), family size (47.8%), absence of toilets (53.5%), irregular use of shoes (48.6%), not wearing shoes (60.0%), irregular hand washing before meals (48.4%) and eating raw food (45.5%) had high infestation rates though with no significance. Multivariate logistic regression analysis showed that people who had never received any treatment had high risks of being infected (p=0.01; OR =0.17; 95% CI = 0.06 to 0.5).
 Conclusion: Improved sanitation, water supply and regular and extended deworming in the entire communities are fundamental issues in controlling intestinal parasitic infections.

Sharing Knowledge With Young and Established Students of Immunology by the Neapolitan Gulf at the Ruggero Ceppellini Advanced School.

In his Origin, Charles Darwin led the foundations to debunk the long-held belief that man and animals derive from separate lineages, landing the final blow in The Descent of Man. The discovery in the mid-1980's that fertilized mammal eggs must have male components to generate healthy offspring had similarly dramatic consequences on other religious beliefs, as discussed in “Genetics: immaculate misconception” (1). In the Catholic calendar, the 8th of December is dedicated to the Virgin Mary. The occasion was celebrated with loud fireworks cracking during the second night of the 25th course of the EFIS-EJI Ruggero Ceppellini Advanced School of Immunology, held at Castellammare di Stabia, near Naples, 7th−9th December 2014. A faculty of 13 gathered together with 60 attendants from 19 countries to discuss the theme Maternal Immune System in Pregnancy. While the conclusions of the course were not quite as dramatic as Darwin's and Surani's, new exciting concepts were discussed that had already emerged at a previous meeting held in Cambridge in 2013 to celebrate the 60th anniversary of Peter Medawar's famous article on the “immunological paradox” of pregnancy (2). I had the honor of directing both events, together with Ashley Moffett, and learned a great deal. This brief article is a report on the activities during that 25th course, as well as an opportunity to celebrate the importance of the Ceppellini School to connect young immunologists with leader scientists in their fields, as well as to spur new collaborations. With the generous support of the EFIS-EJI, the Bill and Melinda Gates Foundation, and the International Union of Immunological Societies, a record number of travel fellowships was offered to 13 participants from African countries, including South Africa, Kenya, Nigeria, Gabon, and Cameroon. This was appropriate because it is in Sub-Saharan Africa (SSA) that maternal morbidity and mortality is highest due to pregnancy complications, such as the hypertensive disorder of pregnancy pre-eclampsia, still birth or intrauterine growth restriction (3).

Quantitative Interpretation of Gravity Anomalies in the Kribi-Campo Sedimentary Basin (South Cameroon) Based on Spectral Analysis and 2.5D Modelling: Structural Implications

Ground gravity survey was recently carried out in the Lolabe-Campo area, which constitutes the southern onshore portion of the Kribi-Campo sub-basin in South Cameroon. The obtained gravity data were processed and interpreted in order to elucidate the subsurface geology of the area in which preliminary studies highlighted the presence of an intrusive igneous body. In order to determine the nature and the characteristics of this body, spectral analysis, ideal body solution and 2.5D modelling methods were applied to the gravity data. The results suggest that the emplacement, breaking up and separation of the intrusive igneous body were the outcome of two tectonic events corresponding to an upward vertical translational tectonic movement followed by an anticlockwise rotational faulting tectonic movement. From a density contrast of 0.13 g&#183cm&#453, the two isolated bodies have an estimated density of 2.80 g&#183cm&#453 which is comparatively higher than the average density of 2.67 g&#183cm&#453 of the autochthonous rocks. These two blocks are completely surrounded by both sedimentary and metamorphic formations and are confined between the depths of 0.6 km and 3.5 km. The highly dense nature of the rocks and their location around the Atlantic Ocean led to the conclusion that the two intrusive bodies are composed principally of gabbro. The disposition and shape of the open zone resulting from the separation of the blocks are suggestive of a trap for the accumulation of hydrocarbons and mineral resources.

Seroprevalence of Chronic Viral Hepatitis B in School Children Aged Less Than 10 Years in the Region of Southern Cameroon

Introduction: Chronic viral hepatitis remain a public health problem worldwide. Being the seventh leading cause of the deaths, it accounts for 1.4 million deaths annually, with 47% related to hepatitis B and 48% to hepatitis C. In Cameroon, screening for hepatitis B surface antigen (HBsAg) is mandatory by the sixth month of pregnancy. This study aimed at evaluating the carriage rate of HBsAg among pupils in the south region, 10 years after the introduction of the pentavalent vaccine in the expanded immunization programme. Material and methods: This study was conducted in schools in Ebolowa (and its neighborhoods), south of Cameroon, during the five months period from November 1st 2015 to March 17th 2016. Eight schools were randomly selected. All children less than 10 years old were enrolled in our study. Children not meeting our selection criteria, or whose data forms were appropriately filled were excluded. Sampling was done by a laboratory technician of the Ebolowa regional hospital and transferred to the laboratory of the Yaounde University Teaching Hospital for analysis. Data was analyzed using the Epi info software. Results: A total of 471 pupils met our selection criteria with a male to female ration of 0.94 (243 females against 228 males). Five children were HBsAg positive, giving an overall prevalence of 1.06%. Among the 471 pupils, only 166 were appropriately vaccinated as per the extended immunization programme, yielding 35.24% coverage. Conclusion: Despite the low immunization coverage rate, there is a positive impact on the prevalence of hepatitis B among children. Everything being equal, improving the immunization coverage as per the EPI will certainly yield lower rates of infection among children, and thus in the long run, within the general population.

Determinants of survival of HIV-infected children aged 6 months to 15 years on follow-up in the town of Ebolowa, Cameroon from 2008 to 2018

Introductionla survie des enfants infectés par le VIH demeure un défi dans les pays en voie de développement. Au Cameroun, la mortalité liée au VIH chez les enfants de moins de 15 ans en 2018 était de 20%. Paradoxalement, la région du Sud Cameroun, malgré une séroprévalence élevée chez les enfants de 4,1% et une couverture en traitement antirétroviral faible de l´ordre de 64%, ne fait pas partie des régions du Cameroun les plus touchées par la mortalité pédiatrique liée au VIH/SIDA. L´objectif de ce travail était de déterminer le taux de survie et identifier ses déterminants chez les enfants âgés de 6 mois à 15 ans, infectés par le VIH.Méthodesune étude de cohorte à collecte de données rétrospective et prospective a été menée de janvier 2008 à décembre 2018 dans trois formations sanitaires prenant en charge les enfants VIH positifs, à Ebolowa dans la région du Sud Cameroun. L´étude s´est faite en deux temps, une phase de collecte rétrospective pour la sélection des dossiers médicaux des enfants VIH positifs répondant aux critères d´inclusion dans les registres de consultation, et une phase de collecte prospective qui nous a permis d´avoir auprès des parents, les informations sur le devenir des enfants. Un consentement éclairé parental a été obtenu au cours de cette deuxième phase. Les données sociodémographiques, cliniques, paracliniques, thérapeutiques, ainsi que le devenir des enfants ont été collectées. Les temps moyens de survie, ainsi que les facteurs associés à la survie ont été déterminés à l´aide du modèle de Kaplan Meier. La régression à risque proportionnel de Cox, nous a permis d´identifier les déterminants de la survie. Notre critère de jugement était le décès. Le niveau de significativité a été fixé à 5%.Résultatsau total, 186 enfants ont été enrôlés. La durée médiane de suivi était de 18,5 mois. Le taux de survie était de 66,7%. La majorité des décès (67%) est survenue avant le sixième mois de suivi. Après analyse multivariée, l´âge inférieur à 2 ans [aHR: 18,6 (6,48-53,59); p=0,001], l´anémie sévère [aHR: 7,69 (1,02-57,9); p=0,04], et la présence d´infections opportunistes [aHR: 4,52 (2,51-8,14); p=0,05] étaient indépendamment et significativement associés à la survie.Conclusionen plus du traitement antirétroviral précoce, un bon suivi clinique et paraclinique est nécessaire pour améliorer la survie des enfants infectés par le VIH.

Roadmap for the Transformation of the South Cameroon Interconnected Network (RIS) into Smart-Grid

This article comes as a contribution to the development of a specific roadmap with the intention to transform the RIS into a smart grid, based on examples experimented in other countries, surveys, interviews with resource people and the master plan of energy development in Cameroon. To set up this roadmap, an audit of the current network reveals many dysfunctions such as regular power outages, imbalances, losses power. The proposed roadmap is structured around three stages which can be summarized as follows: in the short term, the establishment of a reflection committee, his Functional organizational chart and its timeline of activities have been proposed; in the medium term, the deployment of certain equipment such as smart meters; finally, in the long term, the complete transformation of the current network into a smart grid. This will make it possible to integrate the renewable energies which are in development in African countries. It can serve as a guide for the deployment of smart grids in countries of the sub-region of Africa and in Cameroon in particular. The lack of related studies and the non-popularization of results by those who have already worked on those issues, make this paper a greater contribution for energy policy and development, mostly for sub-Saharan African countries.

Status of Insecticide Resistance and Its Mechanisms in Anopheles gambiae and Anopheles coluzzii Populations from Forest Settings in South Cameroon

A key factor affecting malaria vector control efforts in Cameroon is the rapid expansion of insecticide resistance in Anopheles gambiae s.l (An. gambiae) populations; however, mechanisms involved in insecticide resistance in forest mosquito populations are still not well documented yet. The present study was conducted to screen molecular mechanisms conferring insecticide resistance in An. gambiae s.l. populations from the South Cameroon forest region. WHO bioassays were conducted with F0 An. gambiae females aged three to four days from forest (Sangmelima, Nyabessan, and Mbandjock) and urban sites (Yaoundé (Bastos and Nkolondom)), against pyrethroids (permethrin 0.75% and deltamethrin 0.05%) and carbamates (bendiocarb 0.1%). Members of the An. Gambiae s.l. species complex were identified using molecular diagnostic tools. TaqMan assays were used to screen for target site mutations. The expression profiles of eight genes implicated in insecticide resistance were assessed using RT-qPCR. Cuticle hydrocarbon lipids were measured to assess their potential implication in insecticide resistance. Both An. Gambiae and An. coluzzii were detected. An. gambiae was highly prevalent in Sangmelima, Nyabessan, Mbandjock, and Nkolondom. An. coluzzii was the only species found in the Yaoundé city center (Bastos). Low mortality rate to both pyrethroids and bendiocarb was recorded in all sites. High frequency of L1014F allele (75.32–95.82%) and low frequencies of L1014S (1.71–23.05%) and N1575Y (5.28–12.87%) were recorded. The G119S mutation (14.22–35.5%) was detected for the first time in An. gambiae populations from Cameroon. This mutation was rather absent from An. coluzzii populations. The detoxification genes Cyp6m2, Cyp9k1, Cyp6p4, Cyp6z1, as well as Cyp4g16 which catalyzes epicuticular hydrocarbon biosynthesis, were found to be overexpressed in at least one population. The total cuticular hydrocarvbon content, a proxy of cuticular resistance, did not show a pattern associated with pyrethroid resistance in these populations. The rapid emergence of multiple resistance mechanisms in An. Gambiae s.l. population from the South Cameroon forest region is of big concern and could deeply affect the sustainability of insecticide-based interventions strategies in this region.

Amphibian chytrid fungus in Africa – realigning hypotheses and the research paradigm

AbstractThe amphibian chytrid fungus Batrachochytrium dendrobatidis (Bd), responsible for numerous amphibian declines and extinctions, was previously thought to originate from the African continent. This was based on infected museum specimens from early 20th century South Africa, Cameroon and Uganda. Further research on archived specimens from other continents eventually revealed early 20th century records also in Brazil and Japan. Recent robust analysis of genomic diversity and phylogeny of Bd has shown origin from Asia to be more plausible. This raises the issue that the threat of Bd for African amphibians as a novel pathogen has been underestimated. There are now cases where dramatic amphibian declines in disparate mountains on the continent could be attributed to Bd, and this necessitates an urgent realigning of hypotheses and the research agenda for amphibian conservation on the continent. Notably, hotspots of amphibian host naivety include West Africa where this pathogen has so far not been detected. We discuss research gaps that amphibian conservationists might focus on, notably more genomic sequencing of the BdCAPE (the less virulent) lineage to determine its date of emergence, and assessing the susceptibility of different amphibian species to infection, disease and decline to better prioritize conservation actions.

Volume recovery and estimation of commercial volumes of Okan (Cylicodiscus gabunensis Harms) in southern Cameroon

The objective of this study was to quantify the volume of residues and develop volume equations for estimation of commercial outside-bark volumes of Okan (Cylicodiscus gabunensis) at different logging stages. Two hundred and five stems with diameter at breast height (DBH) varying between 65 and 167 cm were cut and scaled (by successive logs) and followed at forest management unit 09 004b in South Cameroon. The relationships between the scaled volumes and the measured dendrometric variables were established using weighted regressions. The largest proportion (>63%) of the total volume of discarded waste was observed at the stump. Modelling the proportion of stem residues, although resulting in a low R2 value, was best described by considering log length and quality class. Commercial volumes were estimated using DBH, the proportion of waste, grade quality and commercial length. Although difficult to estimate, commercial length offers better results compared with the use of grade quality. These results can contribute to better management of Okan’s commercial timber stocks in South Cameroon.

Influence of Crown Effects in Losses: Application on South Cameroon Interconnected Network

Influence of Crown Effects in Losses: Application on South Cameroon Interconnected Network

Malaria Transmission around the Memve'ele Hydroelectric Dam in South Cameroon: A Combined Retrospective and Prospective Study, 2000⁻2016.

Dam constructions are considered a great concern for public health. The current study aimed to investigate malaria transmission in the Nyabessan village around the Memve’ele dam in South Cameroon. Adult mosquitoes were captured by human landing catches in Nyabessan before and during dam construction in 2000–2006 and 2014–2016 respectively, as well as in the Olama village, which was selected as a control. Malaria vectors were morphologically identified and analyzed for Plasmodium falciparum circumsporozoite protein detection and molecular identification of Anopheles (A.) gambiae species. Overall, ten malaria vector species were identified among 12,189 Anopheles specimens from Nyabessan (N = 6127) and Olama (N = 6062), including A. gambiae Giles (1902), A. coluzzii Coetzee (2013), A. moucheti Evans (1925), A. ovengensis Awono (2004), A. nili Theobald (1903), A. paludis Theobald (1900), A. zieanni, A. marshallii Theobald (1903), A. coustani Laveran (1900), and A. obscurus Grünberg (1905). In Nyabessan, A. moucheti and A. ovengensis were the main vector species before dam construction (16–50 bites/person/night-b/p/n, 0.26–0.71 infective bites/person/night-ib/p/n) that experienced a reduction of their role in disease transmission in 2016 (3–35 b/p/n, 0–0.5 ib/p/n) (p < 0.005). By contrast, the role of A. gambiae s.l. and A. paludis increased (11–38 b/p/n, 0.75–1.2 ib/p/n) (p < 0.01). In Olama, A. moucheti remained the main malaria vector species throughout the study period (p = 0.5). These findings highlight the need for a strong vector-borne disease surveillance and control system around the Memve’ele dam.

A-103 Epidemiology and origin of HTLV-1 and related viruses infection

HTLV-1, which is the etiological agent of Adult T cell Leukemia/lymphoma and of Tropical Spastic Paraparesis/HTLV-1 Associated Myelopathy, is not a ubiquitous virus. Indeed, this retrovirus, whose origin is the STLV-1, endemic in many species of Old-World non human primates (NHPs), is present throughout the world with clusters of high endemicity located often nearby areas where the virus is nearly absent. The main endemic areas are the Southwestern part of Japan, Sub-Saharan Africa and South America, the Caribbean area and foci in the Middle East and Australo-Melanesia. The origin of this puzzling geographical or sometimes rather ethnic repartition is probably linked to a founder effect in some groups with the persistence of a high viral transmission rate. Despite different socio-economic and cultural environment, the HTLV-1 prevalence increases gradually with age, especially among women in nearly all highly endemic areas. The number of HTLV-1 infected carriers in the world is estimated to be at least 5–10 millions individuals.1 This is very probably underestimated. In most of the high endemic areas, HTLV-1 is mainly disseminated and maintained in the human population through intra-familial transmission (mother-to-child and by sexual intercourses). More rarely, transmission may also occur by transfusion or intra-venous drug use. In Central Africa, the relative contribution of each of the different transmission routes for HTLV-1/STLV-1 (inter-humans vs inter-species/NHP-Humans) still remains largely unexplored. We have thus performed epidemiological studies in order to get better knowledge on the possible still ongoing STLV-1 retroviral transmission from NHPs to human in a natural setting. These studies were done in populations of high-risk individuals living in villages or settlements in the rain-forest of South Cameroon and Gabon. Bantu and Pygmy groups, who still actively hunt diverse NHP species, inhabit this region. These hunters are thus frequently exposed to the body fluids of these NHPs. Furthermore, many of the NHPs species living in these areas are infected with simian retroviruses, including various STLV-1 strains as well as STLV-3 and STLV-4 strains, and simian foamy viruses. State of the art serologies and different specific and generic PCR studies were performed to detect and characterize the different HTLV infecting these individuals. The main findings were the following: (1) A severe bite by an ape (gorilla ++) or a monkey is a major risk factor for HTLV-1 infection in hunters, of South Cameroon2 and Gabon.3,4 (2) HTLV-3, a new human retrovirus discovered in 2005 by our team, is present in hunters of NHPs from these areas (Richard et al, in preparation). (3) HTLV-4 infections (the second and third discovered strains) of zoonotic origin were characterized in 2 hunters living in Gabon, severely bitten by a gorilla during hunting activities.5 Interspecies transmission, from apes and monkeys to humans, of different STLV and simian foamy viruses are still ongoing in Central Africa. These studies reinforce the fact that apes, especially gorilla, should be considered as keystone reservoirs for human/disease infections (HIV-1P group, HTLV-1b, origin of P. falciparum…). 1. Gessain A, Cassar O. Epidemiological aspects and world distribution of HTLV-1 infection. Front Microbiol. 2012;3:388. 2. Filippone C, et al, and Gessain A. A severe bite from a nonhuman primate is a major risk factor for HTLV-1 infection in hunters from Central Africa. Clin Infect Dis. 2015;60:1667–1676. 3. Kazanji M, et al, and Gessain A. Origin of HTLV-1 in hunters of nonhuman primates in Central Africa. J Infect Dis. 2015;211:361–365. 4. Doren-Djuicy D, et al submitted 2018. 5. Richard L, et al, and Gessain A. Zoonotic transmission of 2 human T lymphotropic virus type 4 strains in hunters bitten by gorillas in Central Africa. Clin Infect Dis. 2016;63:800–803.

Mine versus Wild: a plant conservation checklist of the rich Iron-Ore Ngovayang Massif Area (South Cameroon)

Background and aims – The rapid expansion of human activities in South Cameroon, particularly mining in mountainous areas, threatens this region’s exceptional biodiversity. To comprehend the effects of land-use change on plant diversity and identify conservation priorities, we aim at providing a first comprehensive plant checklist of the Ngovayang Massif, focusing on the two richest plant families, Orchidaceae and Rubiaceae.Location – The Ngovayang Massif Area (NMA) is located in the South Region of Cameroon. It is covered by lowland and submontane rainforest (100 to 1110 m elevation).Methods – We compiled a dataset of 6116 georeferenced herbarium specimens, of which 2787 belong to Rubiaceae and Orchidaceae. We used rarefaction methods to explore sampling and diversity patterns, and investigated the altitudinal distribution of rare and/or threatened taxa.Key results – The NMA, which houses about 1500 vascular plant taxa, is the richest documented area for Rubiaceae in Atlantic Central Africa (ACA) and the fifth for Orchidaceae, with respectively 281 and 111 taxa. Among these taxa, 178 (45%) are endemic to ACA and 67 (17%) are considered globally threatened according to IUCN categories and criteria. We show that higher elevation areas (&gt; 750 m), which are also the main areas targeted for mining, are the richest in endangered and/or rare species. Three new records for Cameroon are reported here.Conclusion – The NMA represents an Important Plant Area of Cameroon as confirmed by its exceptional plant diversity (&gt; 20% of the total Flora of Cameroon), by the concentration of many threatened and/or restricted range species (10 taxa are strict endemics of the massif) as well as by the threat on rare habitats (i.e. the submontane vegetation above ~750 m elevation). A management plan involving in situ and ex situ conservation actions is urgently needed to reduce the potential threats of future mining activities.

Geophysical Data Processing for the Delineation of Tectonic Lineaments in South Cameroon

The processing of aeromagnetic and gravity data of the Northern part of Congo Craton (South Cameroon region), between latitudes 2&amp;deg;30&amp;rsquo;-3&amp;deg;30&amp;rsquo; N and longitudes 12&amp;deg;-13&amp;deg; E, permitted the determination of the structural features ccurring within the Precambrian basement (Ntem Complex) southwards and the Pan-African belt (Yaounde Group) northwards. The maxima of the Horizontal Gradient within the study area, were obtained using the Blakely and Simpson method (1986). Those maxima were used to trace the magnetic lineaments of the study area. Furthermore, the Total Horizontal derivative of the Tilt derivative applied on the residual grid of Bouguer anomaly guaranteed the enhancement of linear structures which were automatically extracted using the CET Grid Analysis algorithm. The superimposition of both magnetic and gravity lineaments allowed us to display the structural framework of the area, whose major trending directions are E-W, ENE-WSW, and NE-SW. These major lineament directions are likely to be linked to one or more than a single tectonic event such as the ENE-WSW/NE-SW trends, considered as the subduction direction of the Congo craton beneath the Pan-African belt. These trends may be linked to the Eburnean orogeny and are also said to be connected to the Central African Shear Zone (CASZ). The geophysical lineaments identified in the study are defined as potential targets along which mineralization may have been formed, considering the economic potential of the area.

Evaluation of NTFPs in the Secondary Forest of Minko’o Village, in the South Cameroon

Non-timber forest products (NTFPs) and some forest tree species are an important source of livelihood to communities. Unfortunately, their potential and uses are much unknown by the population or organization responsible for conservation. It is for this reason that this study was carried out in the village of Minko’o to assess this potential, and to show their importance. A socio-economic survey was carried out in the village and GPS coordinates of the identified NTFPs and forest trees was recorded from the farms/plantations and forest visited. A total of 20 households were surveyed in order to identify the different NTFPs and their utility for the population. Our findings revealed that 50% of the harvest of NTFPs and forest species is done by picking and 45% by collection. Some NTFPs and forest products were known and used by the people. Some of these resources were not known and therefore under exploited. It is the case of Cola (Cola nitida), Soursop (Persea muricata), Akom (Terminalia superba), Mfo (Enantia Chlorantha), Kassimang (Spondias purpurea). Most of NTFPs were grown by the populations and the preferred NTFP was the avocado tree. The forest tree species are mainly used for medicinal purposes. Other trees were used for construction.