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Camille Maadjhou Mba,1 Wilfred Mbacham,1 Eugène Sobngwi,2,3 Jean Claude Mbanya2,3 1Department of Physiological Sciences/Biochemistry, Faculty of Medicine and Biomedical Sciences, University of Yaoundé 1, Yaoundé, Cameroon; 2Department of Internal Medicine and Specialties, Faculty of Medicine and Biomedical Sciences, University of Yaoundé 1, Yaoundé, Cameroon; 3National Obesity Center and Endocrine and Metabolic Diseases Unit, Yaoundé Central Hospital, Yaoundé, CameroonCorrespondence: Camille Maadjhou MbaDepartment of Physiological Sciences/Biochemistry, Faculty of Medicine and Biomedical Sciences, University of Yaoundé 1, PO Box 1364, Yaoundé, CameroonEmail camilya91@yahoo.frPurpose: Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a key regulator of circulating LDL cholesterol. There are inconsistent data in some populations concerning the association between PCSK9, LDL and CRP. The emerging importance of the inhibition of PCSK9 for the treatment of hypercholesterolemia warrants investigations in different populations. The aim of this study from a Sub-Saharan African population was to evaluate the association between PCSK9 and hs-CRP levels and plasma lipid levels in patients with type 2 diabetes (T2D) and obese and lean controls.Patients and methods: A cross-sectional analytical study was conducted in a major hospital in Yaoundé, Cameroon in a cohort of 162 participants (53% females). There were 54 non-obese T2D patients matched for age and sex to 54 obese nondiabetic and 54 nondiabetic lean subjects. PCSK9 level was assessed by sandwich ELISA method and hsCRP by nephelometry.Results: PCSK9 and hs-CRP levels were significantly higher in obese and T2D subjects when compared to lean controls (pr=0.56, p=0.02 and r=0.2 and p=0.1, respectively). Multilinear regression analysis identified BMI as an independent predictor for PCSK9 levels and this association was maintained after adjustment for confounders; adjusted β-coefficient; 36.1 (95% CI; 29.2–47.4). We did not find an association between PCSK9 and any plasma lipid levels in obese and T2D subjects, nor between PCSK9 and hs-CRP levels.Conclusion: Obese and type 2 diabetes subjects have higher PCSK9 levels when compared to lean controls, suggesting that these metabolic states potentially impact PCSK9 levels in Cameroonian patients.Keywords: PCSK9, LDL-cholesterol, type 2 diabetes, obesity more...

Competing Interests: The authors declare no conflict of interest related to this Opinion paper. OA has served as a paid consultant to the World Health Organization, including its Global Malaria Program, and was founding director of the Affordable Medicines Facility for Malaria. PY is a globally recognized expert in supply chain management. RP has served as Director of the United States President’s Malaria Initiative. WM is Executive Director of the Multilateral Initiative on Malaria. more...

Introduction: in areas with intense perennial malaria transmission, limited data is available on the impact of environmental conditions especially rainfall on naturally acquired immunity against promising malaria vaccine candidates. For this reason, we have compared IgG antibody responses specific to Plasmodium spp. derived MSP3 and UB05 vaccine candidates, in plasma of children living in two areas of Cameroon differing in rainfall conditions., Methods: data about children less than 5 years old was collected during the years 2017 and 2018. Next malaria asymptomatic P. falciparum (Pf) infected children were selected following malaria test confirmation. MSP3 and UB05 specific IgG antibody responses were measured in participant´s plasma using enzyme-linked immunosorbent assay (ELISA)., Results: interestingly, IgG antibody responses specific to UB05 were significantly higher (p<0.0001) in Pf-negative children when compared to their asymptomatic Pf-infected counterparts living in monomodal rainfall areas. In contrast, a significantly higher (p<0.0001) IgG response to MSP3 was observed instead in asymptomatic Pf-infected children in the same population. In addition, IgG responses specific to UB05 remained significantly higher in bimodal when compared to monomodal rainfall areas irrespective of children´s Pf infection status (p<0.0055 for Pf-positive and p<0.0001 for negative children). On the contrary, IgG antibody responses specific to MSP3 were significantly higher in bimodal relative to monomodal rainfall areas (P<0.0001) just for Pf-negative children., Conclusion: thus IgG antibody responses specific to UBO5 are a better correlate of naturally acquired immunity against malaria in Pf-negative Cameroonian children especially in monomodal rainfall areas., Competing Interests: The authors declare no competing interests., (Copyright: Loveline Ngu et al.) more...

Background: Accurate, cost-effective, and noninvasive alternative molecular methods are needed for detecting low malaria parasitemia. The currently-used nested polymerase chain reaction (nPCR) requires blood as well as skilled personnel in order to minimise the risk of bloodborne disease transmission. Therefore, this study is aimed at assessing the accuracy of a noninvasive and more affordable malaria diagnosis with saliva using the loop-mediated isothermal amplification (LAMP) technique., Methods: A cross-sectional study was conducted in the Centre and Southwest regions of Cameroon. Matched blood and saliva samples collected from symptomatic and asymptomatic participants were tested for malaria using rapid diagnostic tests, microscopy, PCR, and LAMP. Statistics were performed using R studio software at 95% confidence interval., Results: A total of 100 participants (65% symptomatic and 35% asymptomatic) aged between 1 and 74 years with a balanced gender distribution ratio of 1.08 were included in our study. The prevalence of malaria was 61%, 57%, 59%, 42%, 35%, 17%, and 16% for blood-RDT, blood-PCR, blood-LAMP, blood-RT-LAMP, saliva-PCR, saliva-RT-LAMP, and saliva-LAMP, respectively. Both saliva and blood showed a sensitivity of 43.90% and respective specificities of 68.75% and 57.62%. When using RT-LAMP, sensitivities of 49.38% and 48.21% and specificities of 94.11% and 66.67% were recorded for saliva and blood, respectively. Sensitivities of 70.23% and 73.49% and specificities of 62.5% and 76.47% were recorded, respectively, for saliva-LAMP and saliva-RT-LAMP when compared to saliva-PCR as the gold standard. Saliva-LAMP and saliva-RT-LAMP had a fair agreement ( к = 0.221 and 0.352, respectively) with saliva-PCR. Homemade LAMP and RT-LAMP technologies match the WHO recommendations and after proper validation in a larger sample size, could serve for malaria diagnosis in developing countries., Competing Interests: The authors declare that they have no competing interests., (Copyright © 2022 Palmer Masumbe Netongo et al.) more...

Background: Despite the introduction of efficacious interventions for malaria control, sub-Saharan Africa continues to bear the highest burden of malaria and its associated effects on vulnerable populations, such as pregnant women and children. This meta-ethnographic review contributes to literature on malaria in pregnancy interventions in sub-Saharan Africa by offering insights into the multiple factors that motivate or demotivate women from accessing MiP interventions., Methods: A meta-ethnographic approach was used for the synthesis. Original qualitative research articles published from 2010 to November 2021 in English in sub-Saharan Africa were searched for. Articles focusing on WHO's recommended interventions such as intermittent preventive treatment with sulfadoxine-pyrimethamine, long-lasting insecticidal nets and testing and treatment of Malaria in Pregnancy (MiP) were included. Selected articles were uploaded into Nvivo 11 for thematic coding and synthesis., Results: Twenty-seven original qualitative research articles were included in the analysis. Main factors motivating uptake of MiP interventions were: (1) well organized ANC, positive attitudes of health workers and availability of MiP services; (2) Women's knowledge of the effects of malaria in pregnancy, previous experience of accessing responsive ANC; (3) financial resources and encouragement from partners, relatives and friends and (4) favourable weather condition and nearness to a health facility. Factors that demotivated women from using MiP services were: (1) stock-outs, ANC charges and health providers failure to provide women with ample education on the need for MiP care; (2) perception of not being at risk and the culture of self-medication; (3) fear of being bewitched if pregnancy was noticed early, women's lack of decision-making power and dependence on traditional remedies and (4) warm weather, long distances to health facilities and the style of construction of houses making it difficult to hang LLINs., Conclusions: Health system gaps need to be strengthened in order to ensure that MiP interventions become accessible to women. Additionally, health managers need to involve communities in planning, designing and implementing malaria interventions for pregnant women. It is important that the health system engage extensively with communities to facilitate pregnant women and communities understanding of MiP interventions and the need to support pregnant women to access them., (© 2022. The Author(s).) more...

Background: Ghana has adopted and implemented intermittent preventive treatment using sulfadoxine-pyrimethamine (IPTp-SP) and insecticide-treated nets (ITNs) in an antenatal care (ANC) context to prevent malaria among pregnant women. However, the increased ANC attendance and its frequency facilitated by a free maternal health care policy in Ghana does not correspond with the uptake of IPTp-SP and ITN use among pregnant women. This study sought to elucidate the contextual health system factors influencing the delivery of IPTp-SP and ITN from a related quantitative study conducted in Ghana., Methods: This is the qualitative section of a mixed-methods study design, where audio recorded key informant interviews (KIIs) were conducted with health workers from across health facilities, districts, regional and national health directorates. The KIIs elicited information on health worker knowledge, perceptions, and rationale for the delivery practices of IPTp-SP and ITN revealed in the quantitative findings. The interviews were transcribed and imported into NVivo for analysis. Using the World Health Organization (WHO) Health Systems Framework as the theoretical basis, thematic analysis was conducted under broad themes of the building blocks. Findings are presented in narrative quotes, with a mindmap used to summarize the various health system factors and their interrelated relationship influencing the delivery of IPTp-SP and ITN., Results: Health system factors identified included health staff untrained on malaria delivery directives due to an ineffective trainer of trainer (ToT) system. Additionally, health worker confusion on when to commence SP (at quickening or ≥ 16 weeks) was found to result in delayed start of SP. Stock-outs in facilities due to procurement delays at the national level resulted in missed opportunities to deliver SP to eligible pregnant women at the ANC. Similarly, ITN stock outs led to eligible pregnant women not receiving one at ANC clinics., Conclusion: Poor health worker knowledge on policy directives, a consequence of ineffective training strategy led to delayed delivery of IPTp-SP to eligible pregnant women. Supply chain management challenges related to stock of SP and ITN resulted in missed opportunities to deliver the interventions to pregnant women attending ANC., (© 2022. The Author(s).) more...

Background: Procalcitonin is an inflammatory marker strongly associated with the presence of bacterial infection. It has been considered raised in severe malaria infection as opposed to uncomplicated malaria. There are suggestions that it may be raised only when there is concomitant unnoticeable bacterial infection during a malaria crisis. We aimed to assess the difference in plasma procalcitonin levels between children affected by severe and uncomplicated malaria., Methods: We assessed plasma procalcitonin levels in 83 children diagnosed with malaria with no clinical and biological evidence of concomitant bacterial infection. Severity of malaria was established using WHO guidelines. Procalcitonin was determined using the ELISA method. Non-parametric Mann-Whitney U test was used to compare medians across the 2 groups. Statistical significance was set for all p values < 0.05., Results: Of the 83 participants, 28 had uncomplicated malaria, and 55 had severe malaria. PCT levels were obtained in 24 and 40 subjects of each group, respectively, and were similar in both groups; [2.76 (2.52-2.93) vs 2.74 (2.52-2.98) ng/ml, p = 0.916]. The parasite density was lower in the uncomplicated malaria group than in the severe malaria group, but not statistically significant; [22,192 (9110-44 654) vs 31 684 (13 960-73 500) parasites/μl, p = 0.178]. There was no correlation between the parasite density in the general study population and PCT levels (r = 0.072, p = 0.572)., Conclusion: In the absence of overt bacterial infection, procalcitonin levels are not different between children affected with uncomplicated malaria and those with severe malaria. Therefore, bacterial infection should be thoroughly checked for in children with raised serum procalcitonin diagnosed with severe malaria., (© 2022. The Author(s).) more...

Haptoglobin is a protein involved in protecting the body from the harmful effects of free hemoglobin. The haptoglobin gene exhibits a polymorphism, and the different genotypes do not have the same capacity to combat the free hemoglobin effects. The present study aimed at determining the polymorphic distribution of haptoglobin in sickle cell patients (SCPs) from West Cameroon and their impact on the hematological parameters, as well as clinical manifestations of the disease severity. Haptoglobin genotype of 102 SCPs (SS) and 115 healthy individuals (60 AA and 55 AS) was determined by allele-specific polymerase chain reaction, and the complete blood count was determined using the AutoAnalyser. Results showed that the genotype Hp2-2 was significantly ( p  < 0.05) represented in SS patients (54%) than in controls AA and AS (27% and 29%, respectively), while Hp2-1 was mostly found ( p  < 0.05) in AS (42%) and AA (38%), against 15% in SS. The allelic distribution in SS patients was Hp 2 : 0.613, Hp 1S : 0.304, and Hp 1F : 0.084. In AA and AS controls, the proportions of the Hp 1 and Hp 2 alleles were similar (around 0.5 each), with 0.282 for Hp 1S and 0.218 for Hp 1F in AS and 0.283 for Hp 1S and 0.258 for Hp 1F in AA. The distribution of the haptoglobin genotypes did not reveal any significant difference across hematological parameters and clinical manifestations of disease severity in SCP and controls. SCP with Hp1S-1F genotype presented the highest level of hemoglobin. Although Hp2-2 was more frequent in SS patients, it appeared not to be related to the hematological parameters and to the disease's severity. Further investigations are necessary to explore the impact of Hp polymorphism such as antioxidant, lipid profile, and functionality of some tissues in SCP in Cameroon., Competing Interests: The authors declare no conflicts of interest regarding the publication of this paper., (Copyright © 2021 Christian Bernard Kengne Fotsing et al.) more...

Introduction: Malaria interventions including use of Sulfadoxine-Pyrimethamine as Intermittent Preventive Treatment (IPTp-SP) and distribution of Insecticide Treated Nets (ITNs) have been implemented through ante-natal clinic (ANC) services in Ghana. Yet, the high ANC attendance is not commensurate with the uptake of these interventions, with missed opportunities to deliver the interventions. This study sought to assess the health system factors affecting access and delivery of IPTp-SP and ITN as defined by the Ghana Malaria Policy Guideline to eligible pregnant women attending ANC clinic sessions., Methods: A quantitative cross-sectional study was conducted in the Volta Region of Ghana, with data collected across three levels of health care delivery facilities, including hospitals, health centres and Community-Based Health Planning Service (CHPS) compounds. Data collection included structured observation checklists to document the communication and interaction between the ANC health staff and pregnant women. Additionally, structured questionnaires were used to elicit information on cadre, trainings attended, knowledge and delivery practices of health workers on IPTp-SP and ITN. Stata 16 was used for data analysis, and a defined delivery algorithm was used to compute appropriate and inappropriate delivery practices, using the Ghana policy directive as a guide. Predictors of appropriate delivery were determined using logistic regression analysis., Results: Approximately 97% of the 680 ANC observations had complete information for analysis. Of these, 78% (511/657) were eligible for IPTp-SP after excluding women who have less than 16 weeks of gestation, G6PD deficient, malaria positive and have taken 5 doses of IPTp-SP prior to day of observation. Appropriate delivery of IPTp-SP was 76% (390/511). Despite the availability of SP, 15% (75/511) of all eligible women were not offered the medication and 37% (44/119) of inappropriate delivery was recorded during periods of stock out. ITNs were appropriately delivered to 59% (139) out of 237 eligible women. Thirty-two percent (77/237) of eligible women, mostly continuing ANC clients, were not given ITN despite stock availability., Conclusions: IPTp-SP was appropriately delivered to most of the eligible pregnant women compared to ITN. While stock out of both intervention could account for inappropriate delivery, despite stock availability, IPTp-SP and ITN were not delivered to some eligible women., (© 2021. The Author(s).) more...

Objective Inflammatory markers such as C-reactive protein and procalcitonin have been shown to be independent markers of cardiovascular diseases. We aimed to assess the correlation between serum levels of procalcitonin, C-reactive protein and cardiovascular risk in type 2 diabetes. Methods We carried out a cross-sectional study at a tertiary level reference hospital in Yaounde, Cameroon. We assessed the cardiovascular risk using the Action in Diabetes and Vascular Disease: Preterax and Diamicron-MR Controlled Evaluation (ADVANCE) cardiovascular risk prediction model in 80 adults with type 2 diabetes. Serum procalcitonin and C-reactive protein were measured in 80 and 76 subjects respectively, using a highly sensitive quantitative enzyme-linked immunosorbent assay (ELISA) method. Correlations were examined using Spearman's rank correlation test and the correlation coefficients were compared using the Z-test statistic. Results Females represented the majority of the study population (62.5%). The median duration of diabetes was 5 (3-10) years and 62.5% of participants had a high cardiovascular risk score. Median serum procalcitonin levels was significantly higher in females compared to male participants: 2.48 (1.76-3.01 ng/mL) vs 1.42 (0.86-1.87 ng/mL); p<0.001. There was no difference in the serum C-reactive protein levels between females and males: 1.20 (0.33-3.33) mg/L vs 0.85 (0.36-2.77) mg/L; p=0.669. Procalcitonin was moderately correlated with cardiovascular risk (r=0.58, p<0.001). The correlation was slightly higher in females (R=0.56, p<0.001) versus males (R=0.49, p=0.005) although not significantly different (Z-statistic=0.734, p=0.463). Serum C-reactive protein did not show a meaningful correlation with cardiovascular risk (R=0.23, p=0.050). At a threshold of 2 ng/ml, serum procalcitonin identified participants with a high cardiovascular risk score, with a sensitivity and specificity of 64% and 80% respectively. Conclusion Compared to C-reactive protein, procalcitonin may be a better surrogate marker for cardiovascular risk prediction in this population with type 2 diabetes., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2021, Katte et al.) more...

Background: The feasibility of antiretroviral therapy (ART) monitoring remains problematic in decentralized HIV clinic settings of sub-Saharan Africa. We assessed the rates and correlates of HIV-1 virological failure (VF) and drug resistance (DR) in 2 pre-test-and-treat urban clinic settings of Senegal., Methods: Consenting HIV-1-infected adults (⩾18 years) receiving first-line ART for ⩾12 months were cross-sectionally enrolled between January and March 2015, at the referral outpatient treatment center of Dakar (n = 151) and decentralized regional hospital of Saint-Louis (n = 127). In the 12 months preceding plasma specimens' collection patients at Saint-Louis had no viral load (VL) testing. Significant predictors of VF (VL ⩾ 1000 copies/ml) and DR (clinically relevant mutations) were determined using binomial logistic regression in R software., Results: Of the 278 adults on EFV-/NVP-based regimens, 32 (11.5% [95%CI: 8.0-15.9]) experienced VF. Failing and non-failing patients had comparable median time [interquartile] on ART (69.5 [23.0-89.5] vs 64.0 [34.0-99.0] months; P  = .46, Mann-Whitney U -test). Of the 27 viraemic isolates successfully genotyped, 20 (74.1%) carried DR mutations; most frequent were M184VI (55.6%), K103N (37.1%), thymidine analog mutations (29.6%), Y181CY (22.2%). The pattern of mutations did not always correspond to the ongoing treatment. The adjusted odds of VF was significantly associated with the decentralized clinic site ( P  < .001) and CD4 < 350 cells/mm 3 ( P  < .006). Strong correlates of DR also included Saint-Louis ( P  < .009), CD4 < 350 cells/mm 3 ( P  <. 001), and nevirapine-based therapies (comparator: efavirenz-based therapies; P  < .027). In stratification analyses by site, higher rate of VF at Saint-Louis (20.5% [95%CI: 13.8-28.5] vs 4.0% [95%CI: 1.5-8.5] in Dakar) was associated with nevirapine-based therapies (OR = 3.34 [1.07-11.75], P  = .038), self-reported missing doses (OR = 3.30 [1.13-10.24], P  = .029), and medical appointments (OR = 2.91 [1.05-8.47], P  = .039) in the last 1 and 12 months(s), respectively. The higher rate of DR at Saint-Louis (12.9% [95%CI: 7.6-20.1] vs 2.7% [95%CI: 0.7-6.7] in Dakar) was associated with nevirapine-based therapies (OR = 5.13 [1.12-37.35], P  = .035)., Conclusion: At decentralized urban settings, there is need for enhanced virological monitoring and adherence support. HIV programs in Senegal should intensify early HIV diagnosis for effective test-and-treat. These interventions, in addition to the superiority of efavirenz-based therapies provide a favorable framework for transitioning to the recommended potent drug dolutegravir, thereby ensuring its long-term use., Competing Interests: Declaration of conflicting interests:The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2021.) more...

Background: Co-infection with malaria and intestinal parasites is common in children in Africa and may affect their immune response to a malaria parasite infection. Prior studies suggest that co-infections may lead to increased susceptibility to malaria infection and disease severity; however, other studies have shown the reverse. Knowledge on how co-morbidities specifically affect the immune response to malaria antigens is limited. Therefore, this study sought to determine the prevalence of co-infection of malaria and intestinal parasites and its association with antibody levels to malaria merozoite antigens., Methods: A cross sectional study was carried out in two villages with high transmission of malaria in Cameroon (Ngali II and Mfou) where mass drug administration (MDA) had been administered at ~6-month intervals (generally with albendazole or mebendazole). Children aged 1-15 years were enrolled after obtaining parental consent. A malaria rapid diagnostic test was used on site. Four (4) ml of peripheral blood was collected from each participant to determine Plasmodium falciparum infections by microscopy, haemoglobin levels and serology. Fresh stool samples were collected and examined by wet mount, Kato-Katz method and modified Ritchie concentration techniques. A Multiplex Analyte Platform assay was used to measure antibody levels., Results: A total of 320 children were enrolled. The prevalence of malaria by blood smear was 76.3% (244/320) and prevalence of malaria and intestinal parasites was 16.9% (54/320). Malaria prevalence was highest in young children; whereas, intestinal parasites (IP+) were not present until after 3 years of age. All children positive for malaria had antibodies to MSP142, MSP2, MSP3 and EBA175. No difference in antibody levels in children with malaria-co infections compared to malaria alone were found, except for antibody levels to EBA-175 were higher in children co-infected with intestinal protozoa (p = 0.018), especially those with Entamoeba histolytica infections (p = 0.0026)., Conclusion: Antibody levels to EBA175 were significantly higher in children co-infected with malaria and E. histolytica compared to children infected with malaria alone. It is important to further investigate why and how the presence of these protozoans might modulate the immune response to malaria antigens., Competing Interests: The authors have declared that no competing interests exist. more...

Background: There has been a successful push towards parasitological diagnosis of malaria in Africa, mainly with rapid diagnostic tests (mRDTs), which has reduced over-prescribing of artemisinin-based combination therapies (ACT) to malaria test-negative patients. The effect on prescribing for test-positive patients has received much less attention. Malaria infection in endemic Africa is often most dangerous for young children and those in low-transmission settings. This study examined non-prescription of antimalarials for patients with malaria infection demonstrated by positive mRDT results, and in particular these groups who are most vulnerable to poor outcomes if antimalarials are not given., Methods: Analysis of data from 562,762 patients in 8 studies co-designed as part of the ACT Consortium, conducted 2007-2013 in children and adults, in Cameroon, Ghana, Nigeria, Tanzania, and Uganda, in a variety of public and private health care sector settings, and across a range of malaria endemic zones., Results: Of 106,039 patients with positive mRDT results (median age 6 years), 7426 (7.0%) were not prescribed an ACT antimalarial. The proportion of mRDT-positive patients not prescribed ACT ranged across sites from 1.3 to 37.1%. For patients under age 5 years, 3473/44,539 (7.8%) were not prescribed an ACT, compared with 3833/60,043 (6.4%) of those aged ≥ 5 years. The proportion of < 5-year-olds not prescribed ACT ranged up to 41.8% across sites. The odds of not being prescribed an ACT were 2-32 times higher for patients in settings with lower-transmission intensity (using test positivity as a proxy) compared to areas of higher transmission. mRDT-positive children in low-transmission settings were especially likely not to be prescribed ACT, with proportions untreated up to 70%. Of the 7426 mRDT-positive patients not prescribed an ACT, 4121 (55.5%) were prescribed other, non-recommended non-ACT antimalarial medications, and the remainder (44.5%) were prescribed no antimalarial., Conclusions: In eight studies of mRDT implementation in five African countries, substantial proportions of patients testing mRDT-positive were not prescribed an ACT antimalarial, and many were not prescribed an antimalarial at all. Patients most vulnerable to serious outcomes, children < 5 years and those in low-transmission settings, were most likely to not be prescribed antimalarials, and young children in low-transmission settings were least likely to be treated for malaria. This major public health risk must be addressed in training and practice., Trial Registration: Reported in individual primary studies. more...

In Cameroon, genome characterization of influenza virus has been performed only in the Southern regions meanwhile genetic diversity of this virus varies with respect to locality. The Northern region characterized by a Sudan tropical climate might have distinct genetic characterization. This study aimed to better understand the genetic diversity of influenza A(H3N2) viruses circulating in Northern Cameroon. Sequences of three gene segments (hemagglutinin (HA), neuraminidase (NA) and matrix (M) genes) were obtained from 16 A(H3N2) virus strains collected during the 2014 to 2016 influenza seasons in Garoua. The HA gene segments were analysed with respect to reference strains while the NA and M gene was analysed for reported genetic markers of resistance to antivirals. Analysis of the HA sequences revealed that majority of the virus strains grouped together with the 2016-2017 vaccine strain (3C.2a-A/Hong Kong/4801/2014) while 3/5 (60%) of the 2015 viral strains grouped together with the 2015-2016 vaccine strain 3C.3a-A/Switzerland/9715293/2013. Within clade 3C.2a, Northern Cameroon sequences mostly grouped in sub-clade A3 (10/16). Analysis of the coding regions of the NA and M genes showed that none had genetic markers of resistance to neuraminidase inhibitors but all strains possessed the S31N substitution of resistance to amantadine. Due to some discrepancies observed in this region with respect to the Southern regions of Cameroon, there is necessity of including all regions within a country in the sentinel surveillance of influenza. These data will enable to track changes in influenza viruses in Cameroon., (© 2019 Wiley Periodicals, Inc.) more...

Backround and Objective: Screening for diabetic retinopathy (DR) is cost-effective when compared with disability loss for those who go blind in the absence of a screening program. We aimed to evaluate the sensitivity and specificity of a smartphone-based device for the screening and detection of DR., Patients and Methods: A cross-sectional study of 220 patients with diabetes (440 eyes, all patients age 25 years or older) was completed. Tropicamide 0.5% was used for iris dilation followed by an indirect ophthalmoscopy using a 20-D lens. Retinal images were later obtained using a smartphone attached to an adaptable camera device. Retinal images permitted the visualization of the macular and papillary regions and were sent without compression via the internet to a retinal specialist for interpretation. Sensitivity and specificity were calculated for all cases and stages of DR., Results: Using our standard examination method, the prevalence of DR and macular edema were 13.6% and 6.4%, respectively. With the smartphone-based retinal camera, the prevalence of DR and macular edema were 18.2% and 8.2%, respectively. Sensitivity and specificity for the detection of all stages of DR was 73.3% and 90.5%, respectively. For the detection of macular edema, sensitivity was 77.8%, and specificity was 95%. For severe nonproliferative DR (NPDR), sensitivity and specificity were 80% and 99%, respectively; for proliferative DR (PDR), they were both 100%. In the early stages of DR, specificity was 89.8% for mild NPDR and 97.1% for moderate NPDR. Sensitivity was 57.1% and 42.9%, respectively., Conclusion: Screening for DR using a smartphone-based retinal camera has a satisfactory specificity at all DR stages. Its sensitivity seems to be high only in the stages of DR necessitating a specific therapeutic decision (eg, macular edema, severe NPDR, and PDR). A smartphone-based retinal camera may be a useful device to screen for DR in resource-limited settings. [Ophthalmic Surg Lasers Imaging Retina. 2019;50:S18-S22.]., (Copyright 2019, SLACK Incorporated.) more...

Background: Several studies have demonstrated the role of meteorological parameters in the seasonality of influenza viruses in tropical and subtropical regions, most importantly temperature, humidity, and rainfall., Objectives: This study aimed to describe the influence of meteorological parameters in the seasonality of influenza viruses in Northern Cameroon, a region characterized by high temperatures., Methods: This was a retrospective study performed in Garoua Cameroon from January 2014 to December 2016. Monthly proportions of confirmed influenza cases from six sentinel sites were considered as dependent variables, whereas monthly values of mean temperature, average relative humidity, and accumulated rainfall were considered as independent variables. A vector error correction model was used to determine the relationship between influenza activity and the meteorological variables., Results and Conclusion: Analysis showed that there was a statistically significant association between overall influenza activity and influenza A activity with respect to average relative humidity. A unit increase in humidity within a given month leads to more than 85% rise in the overall influenza and influenza A activity 2 months later. Meanwhile, none of the three meteorological variables could explain influenza B activity. This observation is essential in filling the gap of knowledge and could help in the prevention and control strategies to strengthen influenza surveillance program in Cameroon., (© 2018 The Authors. Influenza and Other Respiratory Viruses Published by John Wiley & Sons Ltd.) more...

In 2009, Influenza A(H1N1)pdm09 caused the first influenza pandemic of the 21st century with high mortality rates of about 284 500 deaths. This virus, however, continues to circulate as a seasonal influenza virus and to cause illness and deaths worldwide. In this study, we describe the genetic diversity of A(H1N1)pdm09 viruses collected between 2014 and 2016 in Cameroon. Three gene segments (HA, NA and M) of Cameroon strains were studied. The phylogenetic tree of the coding nucleotide sequences was generated by MEGA version 6.0 using a Maximum Likelihood method. The NA and M protein coding sequences were analyzed for the reported genetic markers of resistance against neuraminidase inhibitors and adamantanes, while predicted vaccine efficacy was estimated using the Pepitope method. Overall 39 strains were obtained. Phylogenetic analysis of the HA gene of influenza A(H1N1)pdm09 showed that Cameroon strains belonged to two major clades. The 2014 Cameroon sequences belonged to clade 6C while all sequences collected between 2015 and 2016 belonged to clade 6B. Majority of the samples had some mutations in the NA gene notably: I117M, N248D, and N369K while the amantadine-resistant M mutant, S31N, was found to be absent only in the two sequences collected in 2014. Overall, A/California/07/2009 vaccine strain showed a predicted vaccine efficacy of 24.55% to 35.77% against Cameroon A(H1N1)pdm09 strains circulating between 2014 and 2016. Our findings confirms the fast evolution of A(H1N1)pdm09 since its first introduction and highlights on the importance of influenza vaccine in reducing the burden caused by influenza in the community., Competing Interests: The authors have declared that no competing interests exist. more...

In May 2016, highly pathogenic avian influenza virus of the subtype A/H5N1 was detected in Cameroon in an industrial poultry farm at Mvog-Betsi, Yaoundé (Centre region), with a recorded sudden increase of deaths among chickens, and an overall mortality rate of 75%. The virus spread further and caused new outbreaks in some parts of the country. In total, 21 outbreaks were confirmed from May 2016 to March 2017 (six in the Centre, six in the West, eight in the South and one in the Adamaoua regions). This resulted in an estimated total loss of 138,252 birds (44,451 deaths due to infection and 93,801 stamped out). Only domestic birds (chickens, ducks and geese) were affected in farms as well as in poultry markets. The outbreaks occurred in three waves, the first from May to June 2016, the second in September 2016 and the last wave in March 2017. The topology of the phylogeny based on the haemagglutinin gene segment indicated that the causative H5N1 viruses fall within the genetic clade 2.3.2.1c, within the same group as the A/H5N1 viruses collected in Niger in 2015 and 2016. More importantly, the gene constellation of four representative viruses showed evidence of H5N1/H9N2 intra-clade reassortment. Additional epidemiological and genetic data from affected countries in West Africa are needed to better trace the origin, spread and evolution of A/H5N1 in Cameroon. RESEARCH HIGHLIGHTS HPAI A/H5N1 was detected in May 2016 in domestic chickens in Yaoundé-Cameroon. Twenty-one outbreaks in total were confirmed from May 2016 to March 2017. The causative H5N1 viruses fall within the genetic clade 2.3.2.1c. The viral gene constellation showed evidence of H5N1/H9N2 intra-clade reassortment. more...

Objective: Mycobacterium tuberculosis isolates that fail to hybridize to at least one rpoB wild-type or any mutation probe on the Genotype MTBDRplus strip are assumed to be rifampicin-resistant. However, the precise mutation(s) are unknown. We sought to identify the mutations in isolates with such hybridization patterns and determine if the mutations are associated with resistance to rifampicin., Methods: In this study, 275 M. tuberculosis isolates were screened with the Genotype MTBDRplus assay to identify isolates with the hybridization pattern. These isolates were sequenced and their minimum inhibitory concentrations (MIC) determined using the Bactec MGIT 960 system., Results: Among the 275 isolates tested, 15 (6%) isolates with the hybridization pattern were identified. Sequencing showed that failure to hybridize to rpoB wild-type probes resulted from the presence of 'disputed' rifampicin mutations, which are mutations not always associated with a rifampicin-resistant phenotype. All, except 3/15, isolates had a rifampicin-resistant phenotype (MIC > 1 μg/mL). One of the three isolates with a rifampicin-susceptible phenotype had the same mutation at position 526 (His526Leu) as another isolate that had a rifampicin-resistant phenotype., Conclusion: The recommendation of the Genotype MTBDRplus assay to assume rifampicin resistance based solely on failure to hybridize to rpoB wild-type probe allows the identification of important RIF-resistant isolates. About 20% (3/15) of such isolates could be missed by relying only on the standard MGIT 960 DST assay for drug susceptibility testing., (Copyright © 2017 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.) more...

Background: Hypertension holds a unique place in population health and health care because it is the leading cause of cardiovascular disease and the most common noncommunicable condition seen in primary care worldwide. Without effective prevention and control, raised blood pressure significantly increases the risk of stroke, myocardial infarction, chronic kidney disease, heart failure, dementia, renal failure, and blindness. There is an urgent need for stakeholders-including individuals and families-across the health system, researchers, and decision makers to work collaboratively for improving prevention, screening and detection, diagnosis and evaluation, awareness, treatment and medication adherence, management, and control for people with or at high risk for hypertension. Meeting this need will help reduce the burden of hypertension-related disease, prevent complications, and reduce the need for hospitalization, costly interventions, and premature deaths., Objective: This review aims to synthesize evidence on the epidemiological landscape and control of hypertension in Cameroon, and to identify elements that could potentially inform interventions to combat hypertension in this setting and elsewhere in sub-Saharan Africa., Methods: The full search process will involve several steps, including selecting relevant databases, keywords, and Medical Subject Headings (MeSH); searching for relevant studies from the selected databases; searching OpenGrey and the Grey Literature Report for gray literature; hand searching in Google Scholar; and soliciting missed publications (if any) from relevant authors. We will select qualitative, quantitative, or mixed-methods studies with data on the epidemiology and control of hypertension in Cameroon. We will include published literature in French or English from electronic databases up to December 31, 2016, and involving adults aged 18 years or older. Both facility and population-based studies on hypertension will be included. Two reviewers of the team will independently search, screen, extract data, and assess the quality of selected studies using suitable tools. Selected studies will be analyzed by narrative synthesis, meta-analysis, or both, depending on the nature of the data retrieved in line with the review objectives., Results: This review is part of an ongoing research program on disease prevention and control in the context of the dual burden of communicable and noncommunicable diseases in Africa. The first results are expected in 2017., Conclusions: This review will provide a comprehensive assessment of the burden of hypertension and control measures that have been designed and implemented in Cameroon. Findings will form the knowledge base relevant to stakeholders across the health system and researchers who are involved in hypertension prevention and control in the community and clinic settings in Cameroon, as a yardstick for similar African countries., Trial Registration: PROSPERO registration number: CRD42017054950; http://www.crd.york.ac.uk/PROSPERO/ display&#95;record.asp?ID=CRD42017054950 (Archived by WebCite at http://www.webcitation.org/6qYSjt9Jc)., (©Barthelemy Kuate Defo, Jean Claude Mbanya, Jean-Claude Tardif, Olugbemiga Ekundayo, Sylvie Perreault, Louise Potvin, Robert Cote, Andre Pascal Kengne, Simeon Pierre Choukem, Felix Assah, Samuel Kingue, Lucie Richard, Roland Pongou, Katherine Frohlich, Jude Saji, Pierre Fournier, Eugene Sobngwi, Valery Ridde, Marie-Pierre Dubé, Simon De Denus, Wilfred Mbacham, Jean-Philippe Lafrance, Dickson Shey Nsagha, Warner Mampuya, Anastase Dzudie, Lyne Cloutier, Christina Zarowsky, Agatha Tanya, Paul Ndom, Marie Hatem, Evelyne Rey, Louise Roy, Roxane Borgès Da Silva, Christian Dagenais, David Todem, Robert Weladji, Dora Mbanya, Elham Emami, Zakariaou Njoumemi, Laurence Monnais, Carl-Ardy Dubois. Originally published in JMIR Research Protocols (http://www.researchprotocols.org), 29.05.2017.) more...

Background: In sub-Saharan Africa, intense perennial Plasmodium species transmission coincides with areas of high prevalence of the human immunodeficiency virus type 1 (HIV) infection. This implies that antiretroviral naïve HIV-infected people living within these regions are repeatedly exposed to Plasmodium species infection and consequently malaria. Natural killer (NK) cells are known to contribute to malaria immunity through the production of IFN-γ after exposure to Plasmodium falciparum -infected erythrocytes (infected red blood cells [iRBC]). However, in antiretroviral naïve HIV-1 infection, these functions could be impaired. In this study we assess the ability of NK cells from antiretroviral naïve HIV-1-infected people to respond to iRBC., Method: Magnetically sorted NK cells from antiretroviral naïve HIV-1-infected people were tested for their ability to respond to iRBC following in vitro coculture. NK cell IFN-γ production after coculture was measured through multiparametric flow cytometry analysis., Results: Our data show a significant reduction ( p = 0.03) in IFN-γ production by NK cells from antiretroviral naïve HIV-1-infected people after coculture with iRBCs. This was in contrast to the NK cell response from healthy controls, which demonstrated elevated IFN-γ production. NK cell IFN-γ production from untreated HIV-1-infected participants correlated inversely with the viral load ( r = -0.5, p = 0.02) and positively with total helper CD4 + T-cell count ( r = 0.4, p = 0.04). Thus, antiretroviral naïve HIV-1 infection can dampen NK cell-mediated immunity to P. falciparum infection in malaria-intense regions. This could in effect escalate morbidity and mortality in people chronically infected with HIV-1., (Copyright © 2017 by S. Karger AG, Basel.) more...