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Background: With growing use of parasitological tests to detect malaria and decreasing incidence of the disease in Africa; it becomes necessary to increase the understanding of causes of non-malaria acute febrile illness (NMAFI) towards providing appropriate case management. This research investigates causes of NMAFI in pediatric out-patients in rural Guinea-Bissau. Methods: Children 0-5 years presenting acute fever (≥38°) or history of fever, negative malaria rapid diagnostic test (mRDT) and no signs of specific disease were recruited at the out-patient clinic of 3 health facilities in Bafatá province during 54 consecutive weeks (dry and rainy season). Medical history was recorded and blood, nasopharyngeal, stool and urine samples were collected and tested for the presence of 38 different potential aetiological causes of fever. Results: Samples from 741 children were analysed, the protocol was successful in determining a probable aetiological cause of acute fever in 544 (73.61%) cases. Respiratory viruses were the most frequently identified pathogens, present in the nasopharynx samples of 435 (58.86%) cases, followed by bacteria detected in 167 (22.60%) samples. Despite presenting negative mRDTs, P. falciparum was identified in samples of 24 (3.25%) patients. Conclusions: This research provides a description of the aetiological causes of NMAFI in West African context. Evidence of viral infections were more commonly found than bacteria or parasites. [ABSTRACT FROM AUTHOR]

Infection with viruses of animal origin pose a significant threat to human populations. Simian foamy viruses (SFVs) are frequently transmitted to humans, in which they establish a life-long infection, with the persistence of replication-competent virus. However, zoonotic SFVs do not induce severe disease nor are they transmitted between humans. Thus, SFVs represent a model of zoonotic retroviruses that lead to a chronic infection successfully controlled by the human immune system. We previously showed that infected humans develop potent neutralizing antibodies (nAbs). Within the viral envelope (Env), the surface protein (SU) carries a variable region that defines two genotypes, overlaps with the receptor binding domain (RBD), and is the exclusive target of nAbs. However, its antigenic determinants are not understood. Here, we characterized nAbs present in plasma samples from SFV-infected individuals living in Central Africa. Neutralization assays were carried out in the presence of recombinant SU that compete with SU at the surface of viral vector particles. We defined the regions targeted by the nAbs using mutant SU proteins modified at the glycosylation sites, RBD functional subregions, and genotype-specific sequences that present properties of B-cell epitopes. We observed that nAbs target conformational epitopes. We identified three major epitopic regions: the loops at the apex of the RBD, which likely mediate interactions between Env protomers to form Env trimers, a loop located in the vicinity of the heparan binding site, and a region proximal to the highly conserved glycosylation site N8. We provide information on how nAbs specific for each of the two viral genotypes target different epitopes. Two common immune escape mechanisms, sequence variation and glycan shielding, were not observed. We propose a model according to which the neutralization mechanisms rely on the nAbs to block the Env conformational change and/or interfere with binding to susceptible cells. As the SFV RBD is structurally different from known retroviral RBDs, our data provide fundamental knowledge on the structural basis for the inhibition of viruses by nAbs. Trial registration: The study was registered at www.clinicaltrials.gov: https://clinicaltrials.gov/ct2/show/NCT03225794/. Author summary: Foamy viruses are the oldest known retroviruses and have been mostly described to be nonpathogenic in their natural animal hosts. Simian foamy viruses (SFVs) can be transmitted to humans, in whom they establish persistent infection, as have the simian viruses that led to the emergence of two major human pathogens, human immunodeficiency virus type 1 (HIV-1) and human T lymphotropic virus type 1 (HTLV-1). Such cross-species transmission of SFV is ongoing in many parts of the world where humans have contact with nonhuman primates. We previously showed high titers of neutralizing antibodies (nAbs) in the plasma of most SFV-infected individuals. These antiviral antibodies can inhibit cell-free virus entry. Here, we have identified three sites on viral envelope that are targeted by nAbs. We propose that nAbs block the Env conformational change and/or interfere with binding to susceptible cells. We did not observe escape mechanism common in other retroviruses. Our data support the capacity of nAbs to prevent SFV spread. [ABSTRACT FROM AUTHOR]

Background Central Africa is one of the largest areas of high endemicity for human T-cell leukemia virus-1 (HTLV-1). However, no preventive measures are yet implemented to reduce its transmission, which can be sexual, from mother-to-child, or through contaminated blood products. Rare zoonotic transmissions from nonhuman primates (NHPs) have also been reported in this region. Here we investigated the HTLV-1 prevalence and associated risk factors in a rural population in Cameroon. Methods From 2019 to 2021, we performed a cross-sectional survey in the eastern region of Cameroon. HTLV-1 infection was first screened by ELISA, then tested by western blot and envelope gene targeted polymerase chain reaction. Risk factors associated with HTLV-1 infection were identified by logistic regression in univariable and multivariable analyses. Results Among 3400 participants, HTLV-1 prevalence was 1.1% (95% confidence interval [CI],.7–1.5). Factors independently associated with HTLV-1 infection were Pygmy ethnicity (adjusted odd ratio [aOR], 2.9; 95% CI, 1.3–6.2), history of surgery (aOR, 6.3; 95% CI, 2.2–17.8), and NHP bite (aOR, 6.6; 95% CI, 2.2–19.8). Conclusions These results suggest both iatrogenic and zoonotic transmission of HTLV-1 in Cameroon. Further studies are needed to assess the risk of nosocomial transmission of HTLV-1, to guide public health authorities in implementing preventive measures to control HTLV-1 transmission. [ABSTRACT FROM AUTHOR]

Objectives: To formatively evaluate the HIGHER Women consortium’s Mentor Protégée Program (MPP) and derive lessons for successful African women scientist mentorship. Design: Desk review of program documents and cross-sectional surveys of mentors and protégées. Setting: All 10 regions of Cameroon Participants: Women working in health research participating in the MPP. Interventions: Building health research skills and providing support for women to cope within the African psychosocial environment using a holistic approach. Main outcome measures: Formed mentor-protégés duos applying the MPP with measurable accomplishments. Results: The consortium counted 121 members with 103 protégées and 18 mentors. Of 103 protégées, 35 responded to the 2018 survey, while 77 responded to the 2022 survey. Mentioned benefits of the program included an increase in scientific peer-reviewed journal publications and presentations at national and international conferences. In the 2022 survey, a Pearson correlation showed an r of 0.41, which, although not statistically significant (p = .592), suggests a positive correlation between the increased number of peer-reviewed articles and increased number of years as HIGHER Women protégées. Conclusions: Mentorship programs can help over time to bridge the gender gaps within Africa as well as the gaps between African-led research and the rest of the world while making a meaningful contribution to enhancing the quality, diversity, and productivity of researchers. A mentoring program such as the HIGHER Women MPP can be improved by leveraging local and international partners to foster the mentoring program’s sustainability, scalability, and expanded reach. [ABSTRACT FROM AUTHOR]

Early predictions forecasted large numbers of severe acute respiratory syndrome coronavirus (SARS-CoV-2) cases and associated deaths in Africa. To date, Africa has been relatively spared. Various hypotheses were postulated to explain the lower than anticipated impact on public health in Africa. However, the contribution of pre-existing immunity is yet to be investigated. In this study, the presence of antibodies against SARS-CoV-2 spike (S) and nucleocapsid (N) proteins in pre-pandemic samples from Africa, Europe, South and North America was examined by ELISA. The protective efficacy of N specific antibodies isolated from Central African donors was tested by in vitro neutralization and in a mouse model of SARS-CoV-2 infection. Antibodies against SARS-CoV-2 S and N proteins were rare in all populations except in Gabon and Senegal where N specific antibodies were prevalent. However, these antibodies failed to neutralize the virus either in vitro or in vivo. Overall, this study indicates that cross-reactive immunity against SARS-CoV-2 N protein was present in Africa prior to the pandemic. However, this pre-existing humoral immunity does not impact viral fitness in rodents suggesting that other human immune defense mechanisms could be involved. In Africa, seroprevalence studies using the N protein are over-estimating SARS-CoV-2 circulation. [ABSTRACT FROM AUTHOR]

Enterovirus A71 (EV-A71) is a non-polio enterovirus that currently represents a major public health concern worldwide. In Africa, only sporadic cases have been reported. Acute flaccid paralysis and environmental surveillance programs have been widely used as strategies for documenting the circulation of polio and non-polio enteroviruses. To date, little is known about the molecular epidemiology of enterovirus A71 in Africa where resources and diagnostic capacities are limited. To fill this gap in Senegal, a total of 521 non-polio enterovirus isolates collected from both acute flaccid paralysis (AFP) and environmental surveillance (ES) programs between 2013 and 2020 were screened for enterovirus A71 using real-time RT-PCR. Positive isolates were sequenced, and genomic data were analyzed using phylogeny. An overall rate of 1.72% (9/521) of the analyzed isolates tested positive for enterovirus A71. All positive isolates originated from the acute flaccid paralysis cases, and 44.4% (4/9) of them were isolated in 2016. The nine newly characterized sequences obtained in our study included eight complete polyprotein sequences and one partial sequence of the VP1 gene, all belonging to the C genogroup. Seven out of the eight complete polyprotein sequences belonged to the C2 subgenotype, while one of them grouped with previous sequences from the C1 subgenotype. The partial VP1 sequence belonged to the C1 subgenotype. Our data provide not only new insights into the recent molecular epidemiology of enterovirus A71 in Senegal but also point to the crucial need to set up specific surveillance programs targeting non-polio enteroviruses at country or regional levels in Africa for rapid identification emerging or re-emerging enteroviruses and better characterization of public health concerns causing acute flaccid paralysis in children such as enterovirus A71. To estimate the real distribution of EV-A71 in Africa, more sero-epidemiological studies should be promoted, particularly in countries where the virus has already been reported. [ABSTRACT FROM AUTHOR]

The burden of encephalitis and its associated viral etiology is poorly described in Africa. Moreover, neurological manifestations of COVID-19 are increasingly reported in many countries, but less so in Africa. Our prospective study aimed to characterize the main viral etiologies of patients hospitalized for encephalitis in two hospitals in Dakar. From January to December 2021, all adult patients that met the inclusion criteria for clinical infectious encephalitis were enrolled. Cerebrospinal fluids, blood, and nasopharyngeal swabs were taken and tested for 27 viruses. During the study period, 122 patients were enrolled. Viral etiology was confirmed or probable in 27 patients (22.1%), with SARS-CoV-2 (n = 8), HSV-1 (n = 7), HHV-7 (n = 5), and EBV (n = 4) being the most detected viruses. Age groups 40–49 was more likely to be positive for at least one virus with an odds ratio of 7.7. The mortality was high among infected patients, with 11 (41%) deaths notified during hospitalization. Interestingly, SARS-CoV-2 was the most prevalent virus in hospitalized patients presenting with encephalitis. Our results reveal the crucial need to establish a country-wide surveillance of encephalitis in Senegal to estimate the burden of this disease in our population and implement strategies to improve care and reduce mortality. [ABSTRACT FROM AUTHOR]

A new species of freshwater crab of the genus Potamonemus Cumberlidge & Clark, 1992 is described from Mount Manengouba Reserve and Bakossi National Park in the tropical rainforests of southwestern Cameroon, Central Africa. Potamonemus man sp. nov. is recognized by characters of the carapace and chelipeds. In addition, a phylogenetic analysis based on partial sequences of three mitochondrial DNA genes (COI, 12S rRNA, and 16S rRNA) that included representatives of all other freshwater crab genera found in Cameroon recovered each of the new species as a distinct lineage. A diagnosis and illustrations of the new species are provided, and it is compared to the other species of Potamonemus. Brief notes are provided on the ecology of the new species and the two other species of Potamonemus. An identification key to the species of Potamonemus is provided. The conservation status of the genus is discussed. [ABSTRACT FROM AUTHOR]

Ventricular noncompaction or hypertrabeculation is rare and unclassified cardiomyopathy that mostly affects the left ventricle. We report the case of biventricular hypertrabeculation in a 54‐year‐old woman who presented with congestive heart failure de novo associated with arrhythmia in a low‐income setting. We also discussed the therapeutic challenges. [ABSTRACT FROM AUTHOR]

Senegal's status as a leading democracy on the African continent is a contested one, challenged in new ways in each election and yet maintained over time through high levels of citizen participation and vigorous competition. The February 2019 presidential elections was no exception. With the benefit of incumbency advantages, Macky Sall won in the first round against a narrowed set of competitors. His victory reflects three major trends in sub-Saharan Africa today: the politicization and delegitimation of institutions of electoral administration, the rising popularity of "youth" candidates, and the drive toward postelection executive centralization. [ABSTRACT FROM AUTHOR]

Buea gen. nov. is established to accommodate the freshwater crab Potamonemus asylos, from south-western Cameroon, Central Africa. This new genus is defined based on molecular evidence combined with morphological characters of the mandible and the first and second gonopods. Buea asylos comb. nov. is endemic to Cameroon, and is here compared with, and distinguished from, other freshwater crabs occurring in that country. Buea gen. nov. is the fifth freshwater crab genus known from Cameroon. The removal of P. asylos from Potamonemus leaves this genus with two species, P. mambilorum and P. sachsi, both of which are illustrated here and compared with the new genus. An amended key to the Potamonautinae genera is provided. Zoobank ID (LSID) This published work and the nomenclatural acts it contains have been registered in ZooBank, the online registration system for the ICZN. The ZooBank Life Science Identifiers (LSIDs) can be resolved and the associated information viewed through any standard web browser by appending the LSID to the prefix . [ABSTRACT FROM AUTHOR]

Background: The burden of respiratory syncytial virus (RSV) infection remains poorly defined in Africa. To address this, we carried out a descriptive and retrospective pilot study, with a focus on the epidemiology of RSV in Senegal after 4 years of surveillance. Methodology and Results: From January 2012 to October 2015 swabs were collected from consenting ILI outpatients. Viral detection was performed using RV16 kit enabling direct subtyping of RSV-A and B. For the molecular characterization of HRSV, the second hypervariable region of the Glycoprotein (G) gene was targeted for sequencing. We enrolled 5338 patients with 2803 children younger than five years of age (52.5%). 610 (11.4%) were positive for RSV infection: 276 (45.2%) were group A infections, 334 (54.8%) were group B infections and 21 (3.4%) were A/B co-infections. RSV detection rate is significantly higher (P < 0.0001) in children below 5 years. We noted that the annual distribution of RSV varied substantially by season and for the predominant subtype. Globally, results show a clear circulation pattern in the second half of each year; between June and September and possibly extended into November. The majority of RSV-A strains from Senegal clustered with strains that were previously assigned NA1 and novel ON1 genotype sequences. RSV-B sequences from Senegal clustered with the BA9 genotype. At the amino acid level, RSV-A strains from Senegal show proximity with the genotype ON1 characterized by a 72 nt insertion in G, resulting in 24 extra amino acids of which 23 are duplications of aa 261–283. Conclusion: Globally our results show a clear circulation pattern of RSV in the second half of each year, between June and September and possibly extending into November, with children under 5 being more susceptible. Molecular studies identified the novel strains ON1 and BA9 as the major genotypes circulating in Senegal between 2012 and 2015. [ABSTRACT FROM AUTHOR]

Background: Among Influenza neuraminidase inhibitors (NAIs), oseltamivir corresponds to the most widely used agent to treat influenza disease. However since 2001, several cases of resistance to NAIs have been reported for circulating seasonal A(H1N1) Influenza viruses. A direct resistance mechanism may be invoked, involving critical mutations in the viral NA gene that prevent the drug binding to its target. Same phenomenon is reported for adamantanes drugs and mutations in the M2 channel protein gene of Influenza viruses. Methods: Reverse-Transcription/Restriction Fragment Length Polymorphism (RT-PCR/RFLP) method, phenotypic testing for oseltamivir resistance, and sequencing of NA, HA and M2 genes were used in this study. Phylogenetic analyses were performed using BioEdit and Mega 5 softwares for alignment of sequences and phylogenetic trees building respectively. Results: Using a simple RT-PCR/RFLP method, we found that the 86 seasonal A(H1N1) isolates from 2008 bear the oseltamivir resistance-associated mutation (H274Y) in the NA gene. In contrast all isolates isolated in Senegal in 2007 were sensitive to oseltamivir. These results were first confirmed by finding high IC50 values using a phenotypic testing for oseltamivir resistance, and secondly by sequencing the whole NA gene. Regarding M2 gene, no mutation associated to adamantanes resistance was characterized of the isolates Conclusions: The present work provides evidence of circulation of drug-resistant seasonal A(H1N1) viruses during the 2008 influenza season (July to September) in Senegal. The results are in favor of multiple introductions of oseltamivir resistant viruses (ORV) A(H1N1) in Senegal. Phylogenetic analyses of isolates with complete sequences of N1 and HA1 genes showed that they belong to clade 2B and suggest sequential introductions in Africa. [ABSTRACT FROM AUTHOR]

Background: Injuries are quickly becoming a leading cause of death globally, disproportionately affecting sub-Saharan Africa, where reports on the epidemiology of injuries are extremely limited. Reports on the patterns and frequency of injuries are available from Cameroon are also scarce. This study explores the patterns of trauma seen at the emergency ward of the busiest trauma center in Cameroon's capital city. Materials and methods: Administrative records from January 1, 2007, through December 31, 2007, were retrospectively reviewed; information on age, gender, mechanism of injury, and outcome was abstracted for all trauma patients presenting to the emergency ward. Univariate analysis was performed to assess patterns of injuries in terms of mechanism, date, age, and gender. Bivariate analysis was used to explore potential relationships between demographic variables and mechanism of injury. Results: A total of 6,234 injured people were seen at the Central Hospital of Yaoundé's emergency ward during the year 2007. Males comprised 71% of those injured, and the mean age of injured patients was 29 years (SD = 14.9). Nearly 60% of the injuries were due to road traffic accidents, 46% of which involved a pedestrian. Intentional injuries were the second most common mechanism of injury (22.5%), 55% of which involved unarmed assault. Patients injured in falls were more likely to be admitted to the hospital ( p < 0.001), whereas patients suffering intentional injuries and bites were less likely to be hospitalized ( p < 0.001). Males were significantly more likely to be admitted than females ( p < 0.001) Discussion: Patterns in terms of age, gender, and mechanism of injury are similar to reports from other countries from the same geographic region, but the magnitude of cases reported is high for a single institution in an African city the size of Yaoundé. As the burden of disease is predicted to increase dramatically in sub-Saharan Africa, immediate efforts in prevention and treatment in Cameroon are strongly warranted. [ABSTRACT FROM AUTHOR]

Bush fire is a widespread and recurrent feature of the African dry savannas and contributes largely to changes in the composition of vegetation communities. However, the impact on seed regeneration in local species has received little attention. This study evaluates the effects of managed bush fire on seed viability and germination capacity for 10 species of West African acacia (sensu lato), taking into consideration fire intensity (related to the quantity of combustible biomass) and seed location (in, on or above the soil) at the time of the fire.The results indicate that the behavior of different species is related to their taxonomic position. Acacia species belonging to the sub-genus Aculeiferum are characterized by their lack of integument inhibition. The consequences of the passage of fire, depending on the intensity of heat shock, are limited to seed survival: they either retain viability or die. Seeds from the sub-genera Acacia and Faidherbia albida have a hard integument that needs to be scarified in order for germination to ensue. In our study, we show that on the whole, heat shocks cannot scarify the integument of the seeds without resultant lethal damage to their embryos. This is true regardless of seed status (naked or protected by seed pods), seed location (in, on or under the soil) and fire intensity. The only species to manifest an improvement in germination capacity, under certain selective experimental fire conditions, and in relation to the non-scarified control are A. raddiana, A. seyal and A. sieberiana. Nevertheless, germination remains substantially inferior to that obtained after scarification by removal of a small piece of integument.It thus seems conceivable to conclude that, contrary to what takes place in Mediterranean climate ecosystems and the wet tropics, fire does not encourage the in situ germination of different Acacia species. This finding implies that in dry savanna areas, it is not possible to regard fire as an accessory to reforestation or natural regeneration of these species. [Copyright &y& Elsevier]

Thirty isolates of armillaria heimii from western, eastern and southern Africa were cultured for fruit body production in the laboratory. Most isolates fruited easily. Investigation of single-spore progenies revealed that all the isolates do not have the same sexual behavior: some are heterothallic and unifactorial while others are homothallic. Two African isolates belonging to the species armillaria mellea also appeared homothallic. Unifactorial heterothallism has not previously been described in armillaria species. Homothallic behavior has been reported only in a rare European species Armillaria ectypa.

Background: The association of macrophage activation syndrome and primary Sjögren's syndrome has been rarely reported in the literature. We report the first observation of this association in Africa, south of the Sahara, and we discuss the diagnosis and therapeutic challenge.Case Presentation: A 26-year-old Mauritanian and Berber woman was followed for primary Sjögren's syndrome. After a voluntary cessation of her usual background treatment, she was admitted to our department for an outbreak of her illness. A clinical examination revealed anemic syndrome, peripheral polyarthritis, coughing rales at both pulmonary bases, and fever at 39.5 °C. On biologic examination, there was bicytopenia with anemia at 5.70 g/dl, lymphopenia at 796/mm3, a biological inflammatory syndrome with a sedimentation rate at 137 mm in the first hour, C-reactive protein at 97 mg/l, hyperferritinemia at 1778 mg/l (9 normal value), and hypergammaglobulinemia at 20.7 g/l of polyclonal appearance. The triglycerides were 1.95 g/l (1.4 normal value) and the lactate dehydrogenase level was 491 IU/l (1.5 normal value). Cytological examination of a medullary puncture revealed an image of hemophagocytosis. An infectious screening was negative. Thoracic computed tomography showed non-specific interstitial lung disease. A diagnosis of macrophage activation syndrome complicating primary Sjögren's syndrome was selected with a probability of 97.2%, according to H-Score. The evolution was favorable under a treatment including etoposide (VP-16).Conclusion: Macrophage activation syndrome is a rare entity, rarely reported during primary Sjögren's syndrome. Its spontaneous evolution is invariably fatal. There is no consensus on therapeutic treatment. Etoposide is a therapeutic option especially in forms refractory to corticosteroid therapy. [ABSTRACT FROM AUTHOR]

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