The shifts in intergenerational relations in Cameroon and their potential impact on the health of older adults.

INTRODUCTION: Africa is experiencing a gradual demographic shift due to rising life expectancy and increasing urbanisation. In sub-Saharan Africa, elderly individuals typically reside with their children. The rise in life expectancy by almost a decade and the prevalence of precarious living conditions raise concerns about the sustainability of the healthcare system, which has traditionally relied on intergenerational solidarity. METHODS: The research aims to analyse the evolving role of older adults in Cameroonian society and to examine the potential impact of this change on intergenerational relationships and the health of older adults. A qualitative methodology was employed, using intergenerational focus groups in Cameroon. RESULTS: Traditionally, older adults held a central role in knowledge transmission through discourse. However, the modernisation of society is challenging this position.The emergence of new technologies, particularly communication tools, is leading to a questioning of older adults' experiential knowledge. Societal changes are contributing to a decline in respect for older adults in discourse. Older adults deplore these societal changes and fear for their place in society while young people are questioning the central role of older people in society. DISCUSSION: These changes could reduce the sense of usefulness of older people, with negative consequences for their health. Several studies have highlighted the impacts of ageism on the health of older adults in industrialised countries. However, there are little data on the impact of the marginalisation of older adults on their health in industrialising societies. Further research is needed to study the impact on the health of older adults.

Strategic HIV Case Findings among Infants at Different Entry Points of Health Facilities in Cameroon: Optimizing the Elimination of Mother-To-Child Transmission in Low- and- Middle-Income Countries.

BACKGROUND: HIV case finding is an essential component for ending AIDS, but there is limited evidence on the effectiveness of such a strategy in the pediatric population. We sought to determine HIV positivity rates among children according to entry points in Cameroon. METHODS: A facility-based survey was conducted from January 2015 to December 2019 among mother-child couples at various entry points of health facilities in six regions of Cameroon. A questionnaire was administered to parents/guardians. Children were tested by polymerase chain reaction (PCR). Positivity rates were compared between entry points. Associations were quantified using the unadjusted positivity ratio (PR) for univariate analyses and the adjusted positivity ratio (aPR) for multiple Poisson regression analyses with 95% confidence intervals (CIs). p-values < 0.05 were considered significant. RESULTS: Overall, 24,097 children were enrolled. Among them, 75.91% were tested through the HIV prevention of mother-to-child transmission (PMTCT) program, followed by outpatient (13.27%) and immunization (6.27%) services. In total, PMTCT, immunization, and outpatient services accounted for 95.39% of children. The overall positivity was 5.71%, with significant differences (p < 0.001) between entry points. Univariate analysis showed that inpatient service (PR = 1.45; 95% CI: [1.08, 1.94]; p = 0.014), infant welfare (PR = 0.43; 95% CI: [0.28, 0.66]; p < 0.001), immunization (PR = 0.56; 95% CI: [0.45, 0.70]; p < 0.001), and PMTCT (PR = 0.41; 95% CI: [0.37, 0.46]; p < 0.001) were associated with HIV transmission. After adjusting for other covariates, only PMTCT was associated with transmission (aPR = 0.66; 95% CI: [0.51, 0.86]; p = 0.002). CONCLUSIONS: While PMTCT accounts for most tested children, high HIV positivity rates were found among children presenting at inpatient, nutrition, and outpatient services and HIV care units. Thus, systematic HIV testing should be proposed for all sick children presenting at the hospital who have escaped the PMTCT cascade.

Characterization of HIV-1 Reservoirs in Children and Adolescents: A Systematic Review and Meta-Analysis Toward Pediatric HIV Cure.

OBJECTIVE: To conduct a comprehensive, systematic review of the profile of HIV-1 reservoirs in children and adolescents with perinatally acquired HIV infection. STUDY DESIGN: Randomized and nonrandomized trials, cohort studies, and cross-sectional studies on HIV reservoirs in pediatric populations, published between 2002 and 2022, were included. Archived-drug resistance mutations (ADRMs) and the size of reservoirs were evaluated. Subgroup analyses were performed to characterize further the data, and the meta-analysis was done through random effect models. RESULTS: Overall, 49 studies from 17 countries worldwide were included, encompassing 2356 perinatally infected participants (48.83% females). There are limited data on the quantitative characterization of viral reservoirs in sub-Saharan Africa, with sensitive methodologies such as droplet digital polymerase chain reaction rarely employed. The overall prevalence of ADRMs was 37.80% (95% CI 13.89-65.17), with 48.79% (95% CI 0-100) in Africa, 42.08% (95% CI 6.68-82.71) in America, 23.88% (95% CI 14.34-34.90) in Asia, and 20.00% (95% CI 10.72-31.17) in Europe, without any difference between infants and adolescents (P = .656). Starting antiretroviral therapy (ART) before 2 months of age limited the levels of HIV-1 DNA (P = .054). Participants with long-suppressed viremia (>5 years) had lower levels of HIV-1 DNA (P = .027). Pre- and post-ART CD4 ≤29% and pre-ART viremia ≥5Log were all found associated with greater levels of HIV-1 DNA (P = .038, P = .047, and P = .041, respectively). CONCLUSIONS: The pooled prevalence of ADRMs is high in perinatally infected pediatric population, with larger proviral reservoir size driven by delayed ART initiation, a shorter period of viral suppression, and immunovirological failures. Thus, strategies for pediatric HIV functional cure should target children and adolescents with very early ART initiation, immunocompetence, and long-term viral suppression.

Inflammatory profile of vertically HIV-1 infected adolescents receiving ART in Cameroon: a contribution toward optimal pediatric HIV control strategies.

Antiretroviral therapy (ART) has improved the lifespan of people living with HIV. However, their immune system remains in a state of sustained activation/inflammation, which favors viral replication and depletion of helper T-cells with varying profiles according to ART-response. We herein sought to ascertain the inflammatory profile of adolescents living with perinatal HIV-1 infection (ALPHI) receiving ART in an African context. In this cross-sectional and comparative study among ART-experienced ALPHI in Yaoundé-Cameroon, HIV-1 RNA was measured by Abbott Real-time PCR; CD4 cells were enumerated using flow cytometry; serum cytokines were measured by ELISA; HIV-1 proviral DNA was genotyped by Sanger-sequencing; and archived drug resistance mutations (ADRMs) were interpreted using Stanford HIVdb.v9.0.1. Overall, 73 adolescents were enrolled (60 ALPHI and 13 HIV-1 negative peers) aged 15 (13-18) years; 60.00% were female. ART median duration was 92 (46-123) months; median viral load was 3.99 (3.17-4.66) RNA Log10 (copies)/mL and median CD4 count was 326 (201-654) cells/mm3. As compared to HIV-negative adolescents, TNFα was highly expressed among ALPHI (p<0.01). Following a virological response, inflammatory cytokines (IFNγ and IL-12), anti-inflammatory cytokines (IL-4 and IL-10) and inflammation-related cytokines (IL-6 and IL-1ß) were highly expressed with viral suppression (VS) vs. virological failure (VF), while the chemokine CCL3 was highly expressed with VF (p<0.01). Regarding the immune response, the inflammatory cytokine TNFα was highly expressed in those that are immunocompetent (CD4≥500 cell/mm3) vs. immunocompromised (CD4<500 cell/mm3), p ≤ 0.01; while chemokine CCL2 was highly expressed in the immunocompromised (p<0.05). In the presence of ADRMs, IL-4 and CCL3 were highly expressed (p=0.027 and p=0.043 respectively). Among ART-experienced ALPHI in Cameroon, the TNFα cytokine was found to be an inflammatory marker of HIV infection; IFNγ, IL-1ß, IL-6, and IL-12 are potential immunological markers of VS and targeting these cytokines in addition to antiretroviral drugs may improve management. Moreover, CCL3 and CCL2 are possible predictors of VF and/or being immunocompromised and could serve as surrogates of poor ART response.

Polyoxygenated Stigmastane-Type Steroids from Vernonia kotschyana Sch. Bip. ex Walp. and Their Chemophenetic Significance.

Four polyoxygenated stigmastanes (1-4) alongside known analogues (7-8) and flavonoids (5-6) were isolated from a dichloromethane/methanol (1:1, v/v) extract of the whole plant of Vernonia kotschyana Sch. Bip. ex Walp. (Asteraceae). Their structures were determined by means of spectroscopic and spectrometric analysis. The relative stereochemistry of the new compounds was established and confirmed via biosynthesis evidence and cyclization of 1 under acidic conditions. A plausible biosynthetic pathway to the new compounds and the chemophenetic significance of the isolated constituents were also discussed. The crude extract, fractions, and compounds (1-3) were assessed for their antibacterial activity against five highly prevalent bacterial strains. The fractions and compounds showed low to moderate activity with minimal inhibitory concentrations (MICs) > 125 µg/mL.

Constituents of the Stem Bark of Symphonia globulifera Linn. f. with Antileishmanial and Antibacterial Activities.

The chemical investigation of the n-hexane fraction from the methanol extract of the stem bark of Symphonia globulifera Linn f., which displayed good in vitro activity against Leishmania donovani NR-48822 promastigotes (IC50 43.11 µg/mL), led to the isolation of three previously unreported polyprenylated benzophenones, guttiferone U (1), V (2)/W (3), and a new tocotrienol derivative named globuliferanol (4), along with 11 known compounds (5-15). Their structures were elucidated based on their NMR and MS data. Some isolated compounds were assessed for both their antileishmanial and cytotoxic activities against L. donovani and Vero cells, respectively. Guttiferone K (5) exhibited the best potency (IC50 3.30 µg/mL), but with low selectivity to Vero cells. The n-hexane fraction and some compounds were also assessed in vitro for their antibacterial activity against seven bacterial strains. All the samples exhibited moderate to potent antibacterial activity (MICs ≤ 15.6 µg/mL) against at least one of the tested strains.

Constituents of the Stem Bark of Trichilia monadelpha (Thonn.) J. J. De Wilde (Meliaceae) and Their Antibacterial and Antiplasmodial Activities.

The chemical investigation of the EtOH extract from the stem bark of Trichilia monadelpha (Thonn.) J. J. De Wilde afforded two new limonoids (1 and 2): 24-acetoxy-21,25-dihydroxy-21,23-epoxytirucall-7-en-3-one (1) and (6R)-1-O-deacetylkhayanolide E (2), together with eleven known compounds (3-13), including additional limonoids, flavonoids, triterpenoids, steroids, and fatty acid. Their structures were determined using 1D- and 2D-NMR experiments, ESI mass spectrometry, and single crystal X-ray diffraction analysis. The antibacterial and antiplasmodial activities of the extracts, sub-extracts, fractions, and some of the isolated compounds were evaluated in known pathogenic strains, including Staphylococcus aureus and Plasmodium falciparum. Fraction E (n-Hex/EtOAc 30:70, v/v) showed significant activity against S. aureus ATCC 25923 with a MIC value of 3.90 µg/mL, while one of its constituents (epicatechin (9)) exhibited significant activity with MIC values of 7.80 µg/mL. Interestingly, grandifotane A (6) (IC50 = 1.37 µM) and khayanolide D (5) (IC50 = 1.68 µM) were highly active against the chloroquine-sensitive/sulfadoxine-resistant plasmodium falciparum 3D7 strain, unlike their corresponding plant extract and fractions.

Maternal Socio-Demographic Factors and Mother-to-Child Transmission of HIV in the North Region of Cameroon.

Background and Objective: Socio-demographic factors are important risk factors for HIV infection. Maternal socio-demographic factors associated with HIV transmission from mother to child are not well elucidated to our knowledge. This study aimed to assess the maternal socio-demographic factors associated with HIV vertical transmission. Methods: A matched case-control study was conducted among children under 15 years of age born to HIV-infected mothers; using a structured questionnaire. The study was conducted in four health facilities in the North Region of Cameroon from July 2015 to October 2016. HIV- infected children were the cases, and HIV-uninfected children were the controls. One case was matched to nearly 4 controls according to age and sex. A total of 113 HIV-infected mothers of children under 15 years of age were purposively enrolled in the study. A questionnaire was administered to mothers and socio-demographic characteristics were collected. Blood samples were collected from the mother and her child for the determination or confirmation of HIV status. Univariate and multiple logistic regressions were used to assess associations between socio-demographic variables and HIV transmission from mother to child. Results: A total of 113 HIV-infected mothers and 113 children under 15 years of age were enrolled in this study. The majority of the mothers were between the age ranges of 25 years to 34 years. Of the 113 HIV-infected mothers, 69 (61%) were Muslims, 33 (32.1%) were not educated, 88 (77.8%) were unemployed, 80 (70.9%) were married, out of which 49 (61.6%) were engaged in a monogamous union. Of the 113 children (49.6%) were female, 25 (22.1%) were HIV-infected and 88 (77.9%) were HIV-exposed uninfected. At the univariate level, mothers who achieved a primary level of education were less likely to transmit HIV to infants compared to uneducated mothers [OR=0.28; CI (0.08-0.95); p=0.04]; and widows had a higher likelihood of HIV transmission to infants compared to married mothers [OR=4.65; CI (1.26-17.20); p=0.02]. Using multiple logistic regression, the maternal primary education level [aOR=0.32; CI (0.08-0.90); p=0.03] and widowerhood [aOR=7.05; CI (1.49-33.24); p=0.01] remained highly associated with the likelihood of HIV transmission to infants. Conclusion and Global Health Implications: Uneducated mothers and widows had a higher likelihood of mother-to-child transmission of HIV. Our findings should prompt reinforcement of prevention strategies targeting uneducated women and widows.

The mother-to-child transmission of HIV-1 and profile of viral reservoirs in pediatric population: A systematic review with meta-analysis of the Cameroonian studies.

BACKGROUND: The mother-to-child transmission of HIV-1 (MTCT) remains on the major route of HIV-transmission among pediatric populations in Africa. Though a prevention of MTCT (PMTCT) high-priority country, data on the MTCT burdens in Cameroon remains fragmented. OBJECTIVE: We sought to assess the pooled MTCT rate, its risk-factors, and to characterize viral reservoirs of infected-children in Cameroon. METHODS: All relevant observational cohort and cross-sectional studies conducted in Cameroon were searched from PubMed, African Journals Online, Google scholar, ScienceDirect and academic medical education databases. Heterogeneity and publication bias were respectively assessed by the I2 statistic and the Egger/funnel plot test. Meta-analysis was performed using the random effects model. MTCT rate >5% was considered as "high". This review was registered in the Prospero database, CRD42021224497. RESULTS: We included a total of 29 studies and analyzed 46 684 children born from HIV-positive mothers. The overall rate of MTCT was 7.00% (95% CI = 6.07-8.51). According to regions, the highest burden was in Adamaoua-region (17.51% [95% CI:14.21-21.07]) with only one study found. PMTCT option-B+ resulted in about 25% reduction of MTCT (8.97% [95% CI: 8.71-9.24] without option-B+ versus 2.88% [95% CI: 5.03-9.34] with option-B+). Regarding risk-factors, MTCT was significantly associated with the absence of PMTCT-interventions both in children (OR:5.40 [95% CI: 2.58-11.27]) and mothers (OR: 3.59 [95% CI: 2.15-5.99]). Regarding viral reservoirs, a pro-viral DNA mean of 3.34±1.05 log10/mL was observed among 5/57 children and archived HIV drug resistance mutations were identified in pro-viral DNA marker among 21/79 infected-children. CONCLUSION: In spite of the dropdown in MTCT following option-B+ implementation, MTCT remains high in Cameroon, with substantial disparities across regions. Thus, in this era of option-B+, achieving MTCT elimination requires interventions in northern-Cameroon. The variation in pro-viral load in infected-children underlines the relevance of characterizing viral reservoirs for possible infection control in tropical settings.

Antibacterial constituents of Rumex nepalensis spreng and its emodin derivatives.

The CH2Cl2-MeOH (1:1) extract of roots of Rumex nepalensis (Polygonaceae) displayed significant antibacterial activity against five bacterial strains with MICs (62.5-31.2 µg.mL-1). The EtOAc soluble fraction displayed a significant activity against the same strains with MICs (31.2-3.9 µg.mL-1). The purification of the EtOAc fraction yielded one new phenylisobenzofuranone derivative, berquaertiide (1), along with 19 known compounds (2-20). Their structures were elucidated based on the analysis of their NMR and MS data. All the isolated compounds were assessed for their antibacterial activity. Compound 2 was the most active against all the tested strains (15.7 to 1.9 µg.mL-1), while compounds 3-7 displayed good activities on at least one of the tested strains. In addition, seven analogues (21-27) of compound 2 were prepared and further assessed for their antibacterial activity. Compounds 26 and 27 were most active than 2 against Salmonella enterica and Klebsiella pneumoniae with MIC (125 and 15.6 µg.mL-1, respectively).

Protection level of anti-hepatitis B vaccine and immunoglobulin in a pediatric Cameroonian population.

Despite the availability for nearly twenty years of an effective vaccine, hepatitis B remains one of the most frequent viral diseases throughout the world. Mother-to-child transmission is one of the primary routes of transmission in children. To assess the vaccine response in children born to HBV infected mothers. HBsAg-positive consenting mothers registered in the antenatal care (ANC) service database of Centre Hospitalier Dominicain St-Martin de Porres, Yaounde were enrolled with their children. Socio-demographic characteristics were collected using a tested questionnaire. The 5 markers of hepatitis B were tested and the quantification of anti-HBsAg antibodies was done by indirect ELISA method. The data collected was analyzed using Microsoft excel and Epi-info softwares. Out of 5,996 women registered, 143 were identified as HBsAg positive (2.38% prevalence) and none was HBeAg positive. Of these 143 HBsAg positive women, 50 were enrolled in the study. Of the 50 positive mothers, 78 children were included with a mean age ± standard deviation of 2.33±2.86 years. No child was infected with HBV, but all have been exposed to the virus (HBeAb-positive). Overall 64 (82.05%) received at birth both anti-HBs immunoglobulin (HBIG) and a dose of vaccine, while 14 (17.95%) received only the birth dose of vaccine. 72 (92.31%) children received all three recommended doses of vaccine. Vaccine responders were 62.82% (above 10 IU/ml), while 37.18% of children were non-responders; representing a higher risk group if not boosted. The coverage of the anti-HBV vaccine in children in this study was 92.31%. The protection level of 62.82% is below the 95% recommended rate by WHO. The factors sustaining this suboptimal protection should be investigated.

Protection level of anti­hepatitis B vaccine and immunoglobulin in a pediatric Cameroonian population

Despite the availability for nearly twenty years of an effective vaccine, hepatitis B remains one of the most frequent viral diseases throughout the world. Mother to child transmission is one of the primary routes of transmission in children. To assess the vaccine response in children born to HBV infected mothers. HBsAg positive consenting mothers registered in the antenatal care (ANC) service database of Centre Hospitalier Dominicain St Martin de Porres, Yaounde were enrolled with their children. Socio demographic char acteristics were collected using a tested questionnaire. The 5 markers of hepatitis B were tested and the quantification of anti HBsAg antibodies was done by indirect ELISA method. The data collected was analyzed using Microsoft excel and Epi info softwares. Out of 5,996 women registered, 143 were identified as HBsAg positive (2.38% prevalence) and none was HBeAg positive. Of these 143 HBsAg positive women, 50 were enrolled in the study. Of the 50 positive mothers, 78 children were included with a mean age ± standard deviation of 2.33±2.86 years. No child was infected with HBV, but all have been exposed to the virus (HBeAb positive). Overall 64 (82.05%) received at birth both anti HBs immunoglobulin (HBIG) and a dose of vaccine, while 14 (17.95%) received only the birth dose of vaccine. 72 (92.31%) children received all three recommended doses of vaccine. Vaccine responders were 62.82% (above 10 IU/ml), while 37.18% of children were non responders; representing a higher risk group if not boosted. The coverage of the anti HBV vaccine in children in this study was 92.31%. The protection level of 62.82% is below the 95% recommended rate by WHO. The factors sustaining this suboptimal protection should be investigated

Bioactive Arylnaphthalide Lignans from Justicia depauperata.

Eleven previously undescribed arylnaphthalide lignans (1-11) together with seven known compounds were isolated from the whole plant of Justicia depauperata. The structures of 1-11 were elucidated by spectroscopic analysis and mass spectrometry. Compounds 6 (IC50 = 4.1 µM) and 9 (IC50 = 9.5 µM) displayed cytotoxic activity against the KB-3-1 cervical carcinoma cell line. This report provides an insight into the conformational equilibria occurring in the arylnaphthalide lignan constituents of this plant.

Assessment of cardiovascular risk factors among HIV-infected patients aged 50 years and older in Cameroon.

Background: Increasing the longevity of people living with HIV (PLHIV) around the world has been accompanied by an increase in the prevalence of cardiovascular disease (CVD) risk factors and morbidity. The impact of these trends on the epidemiology of CVD among PLHIV is less clear. The aim of this study was to assess the risk factors for CVD, and to estimate these risks at 10 years in PLHIV aged 50 and above. Methods: This was a descriptive and analytical study carried out at Mvog Ada District Hospital in Yaounde, Cameroon from January 2020 to January 2021. Descriptive bivariate analyses were used to present the data. The data are presented as frequencies and percentages for categorical variables, and in terms of means and standard deviations for continuous variables where appropriate. The 10-year CVD risk score was calculated using two tools: the validated Framingham risk score (FRS) (low < 10%, moderate 10-20% and high ≥ 20%) and SCORE score (SSC) (low < 3%, moderate 3-4% and high ≥ 5%). Multiple logistic regression models were constructed to examine the respective relationships between the binary dependent variable high CVD risk (FRS ≥ 20%) and the population group, alcohol consumption (more than 10 glasses of beer per week, or more than 35.7 cl/day) and hypertriglyceridemia (independent variables). A p-value less than or equal to 0.05 was considered statistically significant. Results: A total of 112 people aged 50 and above were enrolled in the study out of 180 people registered at the HIV care unit, that is a participation rate of 62.22%. The average age of the participants was 57.3 ± 6.4 years, and the female/male ratio was 1.6. The majority of participants (53.57%) had normal glycaemia levels (<1.10 g/L), 4.46% were diabetic and 46.40% had high blood pressure. The adherence rate for ARV treatment was 98.20%; most participants (77.20%) were alcohol consumers, and 28.10% of participants had hypertriglyceridemia. The estimates of overall cardiovascular risk in 10 years presented 50.90% of participants with low risk, 33% with moderate risk and 16.10% with high risk. Conclusions: Our study indicated an overall risk of cardiovascular events in 10 years is 16.10%, with the main conditional risk factor being hypertriglyceridemia and alcohol consumption, which appeared to triple the risk of CVD among PLHIV.

Expression profiles of miR3181 and miR199a in plasma and placenta of virally suppressed HIV-1 infected Cameroonian pregnant women at delivery.

Human immunodeficiency virus (HIV)-1 infection during pregnancy reduces the transplacental transfer of protective maternal antibodies needed to confer immunity during early postnatal life. However, the mediation of MicroRNA in this dysregulation is not well understood MicroRNAs 3181 and 199a have been shown to mediate neonatal Fc receptor (FcRn)-like transmembrane antibody transfer and endocytosis respectively but their expression levels in the placenta and plasma in women living with HIV have not been extensively investigated. The objective of this study was to determine how the expression levels of miR-3181 and miR-199a in the placenta and plasma are affected in women chronically infected with HIV who are on antiretroviral therapy (ART) and are virally suppressed at delivery. In this pilot case-control study, plasma and placenta biopsies were obtained from 36 (18 HIV+ and 18 HIV-) Cameroonian women at delivery. MicroRNAs 3181 and 199a expression levels were measured using RT-qPCR, data was analyzed using SPSS22.0 and R 3.60, and p values below 0.05 were considered statistically significant. All the HIV-infected women were on known ART regimens and were virally suppressed. There was no significant difference in the levels of miR-3181 (p>0.05) in the placenta and plasma amongst HIV-infected and HIV uninfected women. The expression levels of miR-199a were significantly greater in the plasma compared to the placenta of HIV+ (p = 0.00005) and HIV- (p = 0.027) women. Moreover, there was a significantly higher (p = 0.02) level of miR-199a in the plasma of women with HIV and their uninfected counterparts. Linear regression models adjusted for systolic pressure showed no significant difference (p>0.05) in the levels of miR-199a and miR-3181 in both the placenta and plasma due to HIV infection. Our findings suggest that even though ART uptake and viral suppression might help in maintaining miR3181 and miR199a levels in the placenta of women with HIV at comparative levels to those of their HIV negative counterparts, the significantly higher levels of miR-199a in the plasma of women with HIV compared to the placenta might highlight lurking systemic dangers and requires further investigation.

Diagnostic performance of a colorimetric RT -LAMP for the identification of SARS-CoV-2: A multicenter prospective clinical evaluation in sub-Saharan Africa.

BACKGROUND: Management and control of the COVID-19 pandemic caused by the severe acute respiratory syndrome coronavirus SARS-CoV-2 is critically dependent on quick and reliable identification of the virus in clinical specimens. Detection of viral RNA by a colorimetric reverse transcription loop-mediated isothermal amplification (RT-LAMP) is a simple, reliable and cost-effective assay, deployable in resource-limited settings (RLS). Our objective was to evaluate the intrinsic and extrinsic performances of RT-LAMP in RLS. METHODS: This is a multicenter prospective observational study of diagnostic accuracy, conducted from October 2020 to February 2021 in four African Countries: Cameroon, Ethiopia, Kenya and Nigeria; and in Italy. We enroled 1657 individuals who were either COVID-19 suspect cases, or asymptomatic and presented for screening. RNA extracted from pharyngeal swabs was tested in parallel by a colorimetric RT-LAMP and by a standard real time polymerase chain reaction (RT-PCR). FINDINGS: The sensitivity and specificity of index RT LAMP compared to standard RT-PCR on 1657 prospective specimens from infected individuals was determined. For a subset of 1292 specimens, which underwent exactly the same procedures in different countries, we obtained very high specificity (98%) and positive predictive value (PPV = 99%), while the sensitivity was 87%, with a negative predictive value NPV = 70%, Stratification of RT-PCR data showed superior sensitivity achieved with an RT-PCR cycle threshold (Ct) below 35 (97%), which decreased to 60% above 35. INTERPRETATION: In this field trial, RT-LAMP appears to be a reliable assay, comparable to RT-PCR, particularly with medium-high viral loads (Ct < 35). Hence, RT-LAMP can be deployed in RLS for timely management and prevention of COVID-19, without compromising the quality of output.

Alteration of the gut fecal microbiome in children living with HIV on antiretroviral therapy in Yaounde, Cameroon.

Multiple factors, such as immune disruption, prophylactic co-trimoxazole, and antiretroviral therapy, may influence the structure and function of the gut microbiome of children infected with HIV from birth. In order to understand whether HIV infection altered gut microbiome and to relate changes in microbiome structure and function to immune status, virological response and pediatric ART regimens, we characterized the gut microbiome of 87 HIV-infected and 82 non-exposed HIV-negative children from Yaounde, a cosmopolitan city in Cameroon. We found that children living with HIV had significantly lower alpha diversity in their gut microbiome and altered beta diversity that may not be related to CD4+ T cell count or viral load. There was an increased level of Akkermansia and Faecalibacterium genera and decreased level of Escherichia and other Gamma proteobacteria in children infected with HIV, among other differences. We noted an effect of ethnicity/geography on observed gut microbiome composition and that children on ritonavir-boosted protease inhibitor (PI/r)-based ART had gut microbiome composition that diverged more from HIV-negative controls compared to those on non-nucleoside reverse-transcriptase inhibitors-based ART. Further studies investigating the role of this altered gut microbiome in increased disease susceptibility are warranted for individuals who acquired HIV via mother-to-child transmission.

Protective Effect of the Combination of Wild-Type Genotypes (G/G and G/G) of CCR2-64V and SDF1-3A' Genes in Serodiscordant Couples in Yaounde-Cameroon.

BACKGROUND: There is growing evidence that polymorphisms in chemokine and chemokine receptor genes influence susceptibility to HIV infection and disease progression. However, not much is documented about the influence of these polymorphisms in HIV serodiscordant couples in Cameroon. OBJECTIVE: The objective of this study therefore was to determine the prevalence and the effect of the polymorphisms of CCR5-Δ32, CCR5 promoter 59029 A/G, CCR2-64I and SDF1-3'A gene in HIV serodiscordant couples in comparison to HIV negative seroconcordant and HIV positive seroconcordant couples in Yaoundé-Cameroon. METHODS: A total of 96 couples were recruited from five hospitals, of which 60 couples were HIV serodiscordant (test group), 18 HIV negative seroconcordant and 18 HIV positive seroconcordant couples were used as controls. Their genotypes for CCR5-Δ32, CCR5 promoter, CCR2 and SDF1 were analyzed using polymerase chain reaction (PCR) and restriction fragment length polymorphism. RESULTS: The allelic frequencies of these genes in the studied population were: 0%, 26.30%, 15.30% and 1.62% respectively for CCR5-Δ32, CCR5 promoter, CCR2 and SDF1. The frequency of the combination of CCR5 promoter and SDF1- (A/A+ G/G) wild-type genotype was higher in HIV-infected partners (82.92%) compared to uninfected partners (56.1%) in HIV serodiscordant couples (p= 0.0001). The combination of wild-type CCR2 and SDF1 genotypes (G/G + G/G) was higher among uninfected partners (80.48%) in HIV serodiscordant couples compared to the infected partners (60.97) (p= 0.005). CONCLUSION: HIV negative partner protection against HIV/AIDS infection may be attributed to the combination of wild-type genotypes (G/G and G/G) of CCR2 and SDF1 genes in HIV serodiscordant couples.

Enhanced passive surveillance dengue infection among febrile children: Prevalence, co-infections and associated factors in Cameroon.

Dengue virus (DENV) causes a spectrum of diseases ranging from asymptomatic, mild febrile to a life-threatening illness: dengue hemorrhagic fever. The main clinical symptom of dengue is fever, similar to that of malaria. The prevalence of dengue virus infection, alone or in association with other endemic infectious diseases in children in Cameroon is unknown. The aim of this study was to determine the prevalence of dengue, malaria and HIV in children presenting with fever and associated risk factors. Dengue overall prevalence was 20.2%, Malaria cases were 52.7% and HIV cases represented 12.6%. The prevalence of dengue-HIV co-infection was 6.0% and that of Malaria-dengue co-infection was 19.5%. Triple infection prevalence was 4.3%. Dengue virus infection is present in children and HIV-Dengue or Dengue- Malaria co-infections are common. Dengue peak prevalence was between August and October. Sex and age were not associated with dengue and dengue co-infections. However, malaria as well as HIV were significantly associated with dengue (P = 0.001 and 0.028 respectively). The diagnosis of dengue and Malaria should be carried out routinely for better management of fever.

Highlighting a population-based re-emergence of Syphilis infection and assessing associated risk factors among pregnant women in Cameroon: Evidence from the 2009, 2012 and 2017 national sentinel surveillance surveys of HIV and syphilis.

BACKGROUND: Syphilis and HIV can be transmitted from pregnant women to their children and they remain a public health problem in Africa. Our study aimed to determine the trends of seroprevalence of HIV/syphilis co-infection and syphilis infection overtime through the national surveillance system in Cameroon and to explore associated risk factors. METHODS: We conducted cross-sectional studies of HIV and syphilis, targeting each year 7000 first antenatal care (ANC-1) attendees at the same sites during the 2009, 2012 and 2017 sentinel surveillance surveys. Pregnant women were enrolled at their ANC-1, sociodemographic and clinical information were collected. HIV and Syphilis test were performed by serial algorithm as per the national guidelines. Trends were assessed for HIV, syphilis and HIV/syphilis by estimating seroprevalence from cross-sectional studies. Associated risk factors were explored using multinomial logistic regression with 4 outcomes: HIV/syphilis co-infection, HIV infection only, syphilis infection only and no infection. RESULTS: Overall, 6 632, 6 521 and 6 859 pregnant women were enrolled in 2009, 2012 and 2017 respectively. In 2017, a total of 3 901 pregnant women enrolled were tested for syphilis. Almost half of them (47.9%) were living in urban area and were aged less than 25 years (44.7%). While HIV epidemic was on a decline (from 7.6% (95% CI: 6.99-8.28) in 2009 to 5.7% (95% CI: 4.93-6.4) in 2017), a huge significant increase of syphilis prevalence was observed (from 0.6% (95% CI:0.40-0.80) in 2009 to 5.7% (95% CI:4.93-6.40) in 2017). Pregnant women residing in rural areas were more likely to be infected with syphilis than those living in the urban area (aOR = 1.8 [95% CI: 1.3-2.4]). Unmarried pregnant women were three time more likely to be infected by HIV/Syphilis Co-infection than married, cohabiting, widow or divorced pregnant women (aOR = 2.8 [95% CI: 1.3-2.4]). Furthermore; living in Northern region was associated with a lower risk of being infected with HIV (aOR = 0.6 [95% CI: 0.5-0.9]) and Syphilis infection (aOR = 0.6 [95% CI: 0.4-0.9]). CONCLUSION: The epidemiological dynamics of syphilis suggests a growing burden of syphilis infection in the general population of Cameroon. Our findings support the fact that while emphasizing strategies to fight HIV, huge efforts should also be made for strategies to prevent and fight syphilis infection especially among HIV positive women, in rural area, and southern regions.