Adult mosquitoes of the sibling species Anopheles gambiae and Anopheles coluzzii exhibit contrasting patterns of susceptibility to four neonicotinoid insecticides along an urban-to-rural gradient in Yaoundé, Cameroon

BACKGROUND

Neonicotinoids are potential alternatives for controlling pyrethroid-resistant mosquitoes, but their efficacy against malaria vector populations of sub-Saharan Africa has yet to be investigated. The aim of the present study was to test the efficacy of four neonicotinoids against adult populations of the sibling species Anopheles gambiae and Anopheles coluzzii sampled along an urban-to-rural gradient.

METHODS

The lethal toxicity of three active ingredients for adults of two susceptible Anopheles strains was assessed using concentration-response assays, and their discriminating concentrations were calculated. The discriminating concentrations were then used to test the susceptibility of An. gambiae and An. coluzzii mosquitoes collected from urban, suburban and rural areas of Yaoundé, Cameroon, to acetamiprid, imidacloprid, clothianidin and thiamethoxam.

RESULTS

Lethal concentrations of neonicotinoids were relatively high suggesting that this class of insecticides has low toxicity against Anopheles mosquitoes. Reduced susceptibility to the four neonicotinoids tested was detected in An. gambiae populations collected from rural and suburban areas. By contrast, adults of An. coluzzii that occurred in urbanized settings were susceptible to neonicotinoids except acetamiprid for which 80% mortality was obtained within 72 h of insecticide exposure. The cytochrome inhibitor, piperonyl butoxide (PBO), significantly enhanced the activity of clothianidin and acetamiprid against An. gambiae mosquitoes.

CONCLUSIONS

These findings corroborate susceptibility profiles observed in larvae and highlight a significant variation in tolerance to neonicotinoids between An. gambiae and An. coluzzii populations from Yaoundé. Further studies are needed to disentangle the role of exposure to agricultural pesticides and of cross-resistance mechanisms in the development of neonicotinoid resistance in some Anopheles species.

Susceptibility of Mangifera indica (Sapindales: Anacardiaceae) cultivars to fruit flies (Diptera: Tephritidae) in 2 agroecological zones of Cameroon

The Sudano-Sahelian and the high Guinea savannahs agroecological zones of Cameroon are suitable for the full development of tree crops, including mango. Unfortunately, fresh fruits exported to local and international markets are frequently rejected due to the presence of fruit fly larvae (Diptera: Tephritidae), resulting in drastic income losses and overuse of chemical control products. To promote sustainable management strategies, a 2-yr study (2020-2021) was conducted in 4 and 3 mixed orchards, respectively. Attacked mangoes showing signs of fruit fly damage were collected and taken to the laboratory to rear and identify fruit flies. Repeated grafting and agroclimatic differences were responsible for dissimilarities between the 2 zones, with 18 and 16 cultivars, respectively. From 2,857 attacked mangoes, 26,707 fruit flies belonging to 4 species were identified: Bactrocera dorsalis, Ceratitis cosyra, Ceratitis fasciventris, and Ceratitis anonae. Climate change was the factor determining the distribution of the 2 most important mango fruit flies: B. dorsalis was a wetland species (dominance/occurrence > 70%), while C. cosyra was a dry-land species (dominance/occurrence > 75%). Both species were responsible for high levels of infestations. Bactrocera dorsalis preferred 3 mango cultivars, namely Palmer and Smith in Zone 1, and Ifack 1 in Zone 2 (infestation > 20 individuals/100 g of mango). The host-plant spectrum of C. cosyra was modified by alternative host plants. Both C. fasciventris and C. anonae were rare. Findings from this study could guide researchers in the development of monitoring tools for fruit fly populations and, subsequently, in reducing the damage they cause to mangoes.

Freshwater macroinvertebrates along the Nigeria-Cameroon border enhance the conservation value of the lower Guinea forest biodiversity hotspot

In Nigeria and tropical Africa, the bias towards the protection of natural sites on account of terrestrial biodiversity or their resultant ecosystem services has led to a considerably low number of freshwater conservation studies in the region. To close this gap, six lotic freshwater systems in three different natural sites (Obudu Mountains, Agbokim Waterfalls, and Cross River National Park) along the Cameroon border of Nigeria were evaluated for the biodiversity of macroinvertebrates and some aspects of water quality in December 2021 and March 2022. Among other macroinvertebrate-related indices, the community conservation index (CCI), which considers the presence of threatened, rare, and notable species, was used for the conservation evaluation of the freshwater systems. The Ephemeroptera-Plecoptera-Trichoptera (EPT) species were notably rich at the sites, with over 12 species each at the Afundu Stream, Kwa River, Cataract Stream, and Agbokim River. All of the sites had a very high conservation value, according to the CCI, which was greater than 20. Some Obudu sites (Grotto and Becheve streams), despite having fewer EPT taxa, had higher CCI than the Kwa or Agbokim River. This was due to the presence of the endangered damselflies (Africocypha centripunctata and Allocnemis vicki) at the Obudu sites and a rare mayfly species in Nigeria (Tricorythus tinctus), which was reported at Agbokim and Kwa Rivers. The presence of a notable damselfly genus (Pentaphlebia) at the Afundu stream of the Obudu Mountains also raises some hope that the critically endangered damselfly (Pentaphlebia gamblesi), whose adult was last seen in 1973, could still be alive at the site. Canonical Correspondence Analysis revealed that the proportion of scrapers had a strong association with high BOD and EC in Agbokim River, while the Becheve and Grotto streams which had high vegetal cover was positively associated with shredders. Also, increasing DO in Afundu Stream, Kwa River and Cataract Stream was positively associated with EPT richness. This study revealed that more freshwater ecological studies need to be conducted at isolated natural sites and protected areas in Africa. Findings from such studies have implications for preserving freshwater ecosystems of high conservation value from the various threats that characterize the Anthropocene.

Knowledge, attitudes and practices of contraceptive methods among students in public and private high schools in Cameroon

The use of contraceptive methods is still a controversial subject in the societies of developing countries. This study aims to assess the knowledge, attitudes, and practices of contraceptive methods among students, aged 15 to 25 years, in public and private schools in the district of Bonaberi, Douala, Cameroon. This research was modeled on the pattern of descriptive study. The population in this study was composed of students (N = 1649) from the five public and private high schools of Bonaberi, Cameroon. The sample size of this study was 379 students. These data were collected in person by the researcher between 1 and 30, June 2022. The data collection tools are the student information form, the Knowledge and Practices of Contraceptive Methods Questionnaire, and the Contraceptive Attitude Scale (CAS). The data of this study were analyzed using descriptive statistics tests, Kruskal-Wallis Test, Pearson Chi-Square, Kolmogorov-Smirnoff, Student's T-Test, Mann-Whitney Test, and the One-way ANOVA. It was found that almost half (45.91 percent) of students were 19-22 years old, 59.1 percent of them were male, and almost half (49.3 percent) of them were sexually active. Currently, the male condom is the most commonly used and known method of contraception among students. It was determined that students take an average of 3.406 points from the total score of CAS. This result indicated a positive attitude toward contraceptive methods. There were no statistically significant differences in contraceptive attitudes according to gender, religion, or sexual activity. There was a statistically significant difference in contraceptive attitudes according to marital status and age. It is recommended to provide family planning counseling services in these schools in order to increase the use of effective methods and provide students with a reliable source of information on contraceptive methods.

Cameroon's slow fertility transition: A gender perspective

We interrogate the proposition that men's attitudes have constrained the fertility transition in Cameroon, where fertility remains high and contraceptive use low despite much socio-economic progress. We use five Demographic and Health Surveys to compare trends in desired family size among young women and men and analyse matched monogamous couple data from the two most recent surveys to examine wives' and husbands' desires to stop childbearing and their relative influence on current contraceptive use. In 2018, average desired family size was 5.6 and 5.1, for young men and women respectively, and this difference (half a child) has not changed since 1998. Among matched couples, the proportions wanting to stop childbearing were similar in wives and their husbands, but wives perceived husbands to be much more pronatalist than themselves. Surprisingly, men's own reported preferences were more closely associated with contraceptive use than wives' perceptions of husbands' preferences. We discerned little evidence that men's attitudes have impeded reproductive change.

Building capacity for point of care alcohol-based handrub (ABHR) and hand hygiene compliance among health care workers in the rural maternity and surgical units of a hospital in Cameroon

BACKGROUND

Hand hygiene (HH) is challenging in health care, but particularly in resource-limited settings due to a lack of training, resources, and infrastructure. This study aimed to evaluate the implementation of wall-mounted alcohol-based handrub (ABHR) at the point of care (POC) on HH compliance among health care workers in a Cameroon hospital.

METHODS

It was a three-stage before and after study. The first stage involved baseline collection of ABHR utilization and HH compliance data. The second stage included the implementation of ABHR at the POC, supported by an implementation strategy involving HH training, monitoring and feedback, and HH champions. The third stage involved postimplementation data collection on ABHR use and HH compliance.

RESULTS

5,214 HH opportunities were evaluated. HH compliance significantly increased from 33.3% (baseline) to 83.1% (implementation stage) (P < .001) and to 87.2% (postimplementation stage) (P < .001). Weekly ABHR usage increased significantly during implementation (5,670 ml), compared to baseline, (1242.5 ml, P = .001), and remained high in postimplementation (7,740 ml).

CONCLUSIONS

Continuous availability of ABHR at POC, supported by implementation strategy, significantly increased HH compliance and ABHR use. Learning from this study could be used to implement ABHR at POC in other facilities.

The global atlas of edible insects: analysis of diversity and commonality contributing to food systems and sustainability

The future of the food system on the planet is increasingly facing uncertainties that are attributable to population growth and a surge in demand for nutritious food. Traditional agricultural practices are poised to place strain on production, as well as natural resources and ecosystem services provided, particularly under a changing climate. Given their remarkable attributes, including a low environmental footprint, high food conversion ratio, rapid growth and nutritional values, edible insects can play a vital role in the global food system. Nonetheless, substantial knowledge gaps persist regarding their diversity, global distribution, and shared characteristics across regions, potentially impeding effective scaling and access to edible insects. Therefore, we compiled and analysed the fragmented database on edible insects and identified potential drivers that elucidate insect consumption, globally, focusing on promoting a sustainable food system. We collated data from various sources, including the literature for a list of edible insect species, the Global Biodiversity Information Facility and iNaturalist for the geographical presence of edible insects, the Copernicus Land Service library for Global Land Cover, and FAOSTAT for population, income, and nutritional security parameters. Subsequently, we performed a series of analytics at the country, regional and continental levels. Our study identifies 2205 insect species, consumed across 128 countries globally. Among continents, Asia has the highest number of edible insects (932 species), followed by North America (mainly Mexico) and Africa. The countries with the highest consumption of insects are Mexico (450 species), Thailand (272 species), India (262 species), DRC (255 species), China (235 species), Brazil (140 species), Japan (123 species), and Cameroon (100 species). Our study also revealed some common and specific practices related to edible insect access and utilisation among countries and regions. Although insect consumption is often rooted in cultural practices, it exhibits correlations with land cover, the geographical presence of potentially edible insects, the size of a country's population, and income levels. The practice of eating insects is linked to the culture of people in Africa, Asia, and Latin America, while increased consciousness and the need for food sustainability are driving most of the European countries to evaluate eating insects. Therefore, edible insects are becoming an increasingly significant part of the future of planetary food systems. Therefore, more proactive efforts are required to promote them for their effective contribution to achieving sustainable food production.

Assessment of knowledge and self-efficacy among health professionals and clinical scientists following the Cameroon HIV/AIDS Research Forum (CAM-HERO 2022) research methodology and bioethics training

To inform public health policymakers that the generation of local evidence-based knowledge is key. Research capacity in low- and middle-income countries (LMIC) to generate medical knowledge is often weak and insufficiently resourced and efforts to tackle these challenges are not standardized. Continuous research training can equip researchers with the required knowledge and research skills, but its effectiveness largely depends on the quality and pertinence of the training methods used. We aim to assess the effectiveness of the Cameroon HIV/AIDS Research Forum (CAM-HERO) 2022 Research Methodology and Bioethics Training with the objective to describe the knowledge gained and the self-efficacy of health professionals and clinical scientists. A survey was conducted during the one-day training among health professionals and clinical scientists. Participants took an online self-administered questionnaire before and after the training related to the topics taught. The questionnaire consisted of two parts: 1) 18 Multiple Choice Questions (MCQs) to assess knowledge and 2) Nine items to evaluate self-efficacy using a five-point Likert scale. Mean scores were calculated, analysed, and compared using paired t-test for the pre- and post-test results. A total of 30 participants (57% women) completed the socio-demographic form. The median age (IQR) of participants was 33.5 (13.3) years. We registered 38 respondents for the pre-test and 33 respondents for the post-test. There was a rise in knowledge mean score from 13.0 to 14.8 (p=0.001) and an improvement in the perception of self-efficacy with a mean score increase from 2.9 to 3.7 (p < 0.001). Knowledge and perception of self-efficacy on research methodology improved among participants after the training. These results suggest that the CAM-HERO 2022 training had an immediate positive impact on skills and self-efficacy. Hence, we recommend the implementation of this training on a larger scale, periodically, and with long-term follow-up to evaluate its impact.

Availability of the current and future water resources in Equatorial Central Africa: case of the Nyong forest catchment in Cameroon

To anticipate disasters (drought, floods, etc.) caused by environmental forcing and reduce their impacts on its fragile economy, sub-Saharan Africa needs a good knowledge of the availability of current water resources and reliable hydroclimatic forecasts. This study has an objective to quantify the availability of water resources in the Nyong basin and predict its future evolution (2024-2050). For this, the SWAT (Soil and Water Assessment Tool) model was used. The performance of this model is satisfactory in calibration (2001-2005) and validation (2006-2010), with R2, NSE, and KGE greater than 0.64. Biases of - 11.8% and - 13.9% in calibration and validation also attest to this good performance. In the investigated basin, infiltration (GW_RCH), evapotranspiration (ETP), surface runoff (SURQ), and water yield (WYLD) are greater in the East, probably due to more abundant rainfall in this part. The flows and sediment load (SED) are greater in the middle zone and in the Southwest of the basin, certainly because of the flat topography of this part, which corresponds to the valley floor. Two climate models (CCCma and REMO) predict a decline in water resources in this basin, and two others (HIRHAM5 and RCA4) are the opposite. However, based on a statistical study carried out over the historical period (2001-2005), the CCCma model seems the most reliable. It forecasts a drop in precipitation and runoff, which do not exceed - 19% and - 18%, respectively, whatever the emission scenario (RCP4.5 or RCP8.5). Climate variability (CV) is the only forcing whose impact is visible in the dynamics of current and future flows, due to the modest current (increase of + 102 km2 in builds and roads) and future (increase of + 114 km2 in builds and roads) changes observed in the evolution of land use and land cover (LULC). The results of this study could contribute to improving water resource management in the basin studied and the region.

Histoplasmosis peritonitis in an immunocompetent patient: case report

Histoplasmosis is a fungal infection most frequently seen in immunocompromised patients. It is endemic in Central and South America and in Africa. The infection is usually asymptomatic in a healthy individual. Extrapulmonary dissemination can be seen in immunocompromised hosts. Gastrointestinal manifestations frequently involve the terminal ileum and cecum, mimicking Crohn's disease or malignancy. We describe the case of a 36-year-old healthy man from Cameroon, living in Switzerland for 13 years and without any medical nor surgical history, who presented peritonitis not responding to antibiotics. CT-scan showed bowel obstruction and signs of peritonitis. We opted for an explorative laparoscopy, which was converted to laparotomy with extensive adhesiolysis. Diagnostic of histoplasmosis was confirmed by histology and PCR analysis on biopsy. To our knowledge, this is the first described case of peritonitis as main outcome of a disseminated histoplasmosis involving the peritoneum in an immunocompetent patient.

The management of rare disease patients from a grassroot perspective: the role of patients' organizations in the global recognition of rare diseases in Cameroon

Introduction

rare diseases (RD) are extremely complex health conditions. Persons affected by these conditions in Cameroon are often neglected in society and health systems through the inexistence of policies and programs. In Cameroon, there exists no program or policy conceived to address their needs in terms of access to quality health care, timely and reliable diagnosis, treatments, education, etc. The consequence is that persons living with a RD (PLWRD) and their families do not participate in social life. The unique fate of PLWRD reveals that the principle of social justice and equity is flawed in Cameroon. However, patients, in order to survive in society, rely on patients' organizations (PO) to improve their quality of life (QoL) and advocate for a better consideration in the society. The aim of this paper is to highlight how initiatives from a grassroot perspective like POs can inform decision-makers to address the needs of PLWRD and their families.

Methods

the study associated a systematic literature review and semi-structured interviews with parents of children suffering from a RD and who are members of a PO. Through the systematic literature review we highlighted the impact POs have in the development of research on RDs, patient literacy, patient empowerment and advocacy while semi-structured interviews brought out the needs of patients and their families.

Results

findings, on the one hand show that, in Cameroon PLWRD face a number of challenges like the incurability of their condition, catastrophic medical expenses, stigmatization and marginalization, etc. and though in POs their QoL still remains poor. On the other hand, where POs are empowered they are key actors in research on RDs and help decision-makers on having a better insight into the type of RD that exists across a geographical area, the sociodemographic profile of patients, etc. for a better management of PLWRD.

Conclusion

the study suggests that the ministry of public health should create a network with existing RD POs to adequately meet the needs of PLWRD.

Factors associated with the use of digital health among healthcare workers in the Buea and Tiko health districts of Cameroon: a cross-sectional study

Introduction

digital health has been demonstrated to improve the efficiency and scale of health service delivery in resource-limited settings. Understanding factors influencing its use could accelerate the process of its implementation in routine practice.

Methods

we conducted a cross-sectional analytic study in Buea and Tiko health districts from January to May 2021. We included healthcare workers selected using multistage stratified sampling. Use of digital health was defined as using at least two digital tools and one digital health intervention (DHI) or at least two DHIs by a healthcare worker. Epi Info was used for statistical analysis. Binary logistic regression was used to evaluate factors associated with the use of digital health.

Results

in total, 221 participants were included in the study. The mean age was 33±9.1 years and 76.5% were female. Only 39.4% (n=87) of participants used digital health. The most frequently used digital tools for health-related purposes included: Microsoft (MS) Excel (29.9%), MS PowerPoint (26.8%) and MS Word (39.1%). The main DHIs used were research (30.2%) and diagnosing (24.1%) software. The main use of digital health was for research (75.6%). Owning a laptop (adjusted odds ratio (aOR)=1.98, 95% CI, 1.01 - 3.86), availability of internet connection in the health facility (1.99, 1.05 - 3.7) and receiving professional training in ICT/Computer Sciences (2.04, 1.06 - 3.93), were associated with higher odds of using digital health.

Conclusion

this study shows a low level of use of digital health by healthcare workers. Providing newer devices, internet connection in health facilities and training in ICT for healthcare workers could improve its uptake.

Genetic diversity and natural selection of apical membrane antigen-1 (ama-1) in Cameroonian Plasmodium falciparum isolates

Antigenic variation associated with genetic diversity in global Plasmodium falciparum apical membrane antigen-1 (PfAMA-1) is a major impediment to designing an effective malaria vaccine. Here, we report the first study on genetic diversity and natural selection of the Pfama-1 gene in P. falciparum isolates from Cameroon. A total of 328 P. falciparum positive samples collected during 2016 and 2019 from five localities of Cameroon were analysed. The ectodomain coding fragment of Pfama-1 gene was amplified for polymorphism profiling and natural selection analysis. A total of 108 distinct haplotypes were found in 203 P. falciparum isolates with considerable nucleotide diversity (π = 0.016) and haplotype diversity (Hd = 0.976). Most amino acid substitutions detected were scattered in ectodomain-I and few specific mutations viz P145L, K148Q, K462I, L463F, N471K, S482L, E537G, K546R and I547F were seen only in Cameroonian isolates. A tendency of natural selection towards positive diversifying selection was observed (Taj-D = 2.058). Five positively selected codon sites (P145L, S283L, Q308E/K, P330S and I547F) were identified, which overlapped with predicted B-cell epitopes and red blood cell (RBC) binding sites, suggesting their potential implication in host immune pressure and parasite-RBC binding complex modulation. The Cameroonian P. falciparum populations indicated a moderate level of genetic differentiation when compared with global sequences, with few exceptions from Vietnam and Venezuela. Our findings provide baseline data on existing Pfama-1 gene polymorphisms in Cameroonian field isolates, which will be useful information for malaria vaccine design.

Underestimation of potentially traumatic events resulting from underreporting of physical and sexual violence among people entering care for HIV in Cameroon

OBJECTIVE

Measures ascertaining exposure to potentially traumatic events (PTEs) frequently ask respondents about experienced physical and sexual violence. However, little is known about the performance of physical and sexual violence questions on PTE assessments and its effect on PTE classification overall. We estimated underreporting of physical and sexual violence on a PTE assessment among individuals entering HIV care in Cameroon.

METHOD

We compared reports of physical and sexual violence captured via a behaviorally specific measure of intimate partner violence (IPV; Demographic and Health Survey [DHS] domestic violence module = referent) to those captured via two single-item questions that assessed exposure to physical and sexual PTEs during one's adult life to determine the degree of underreporting on the single-item PTE assessment questions. We explored correlates of underreporting on the PTE assessment using Pearson's chi-squared tests.

RESULTS

Overall, 99 (23%) and 113 (27%) of 426 total participants reported instances of sexual and physical violence in their most recent partnership on the behaviorally specific DHS IPV module, respectively. Of those reporting sexual and physical IPV on the DHS module, just 6% (n = 6) and 52% (n = 59) reported sexual and physical violence as an adult on the single-item PTE assessment questions, respectively. Underreporting of physical violence on the PTE assessment was associated with lower educational attainment (p < .05) and reporting being punched (p < .01) or having one's hair pulled or arm twisted (p < .05) by one's most recent partner.

CONCLUSIONS

PTE assessment tools should assess exposure to behaviorally specific acts of violence to ensure appropriate referral to services among survivors of IPV. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

First detection of Rift Valley fever virus antibodies in non-human primates in Cameroon

We tested for Rift Valley fever virus (RVFV) from at least 15 species of non-human primates. RVFV IgG/IgM antibodies were detected in 3.7% (2 out of 53) of chimpanzees (Pan troglodytes) and in 1.4% (1 out of 72) of unidentified non-human primate species. This study was the first investigation of RVFV in monkeys in Cameroon.

Charting a Course: Navigating Rigor and Meaning in Global Health Research

In the rapidly evolving landscape of global health research, the tension between scientific rigor and contextual meaning presents a critical challenge. Drawing on our work with the Global Diet and Physical Activity Network, this commentary explores the complexities of conducting environmental audits for physical activity and diet in 4 rapidly urbanizing African cities: Yaoundé, Lagos, Cape Town, and Soweto. We illustrate the competing demands and tensions that researchers face in balancing rigor and meaning. We discuss the adaptation of internationally validated audit tools to local contexts and the importance of area-level deprivation in interpreting data. We also examine the feasibility of virtual assessment tools, emphasizing the value of local expertise. We argue for a balanced approach that marries research rigor with contextual meaning, advocating for transparency, humility, and meaningful community engagement.

Leukocyte ratios in non-diabetic hypertensive Cameroonians do not predict cardiovascular risk : preliminary results of the HYRICCA project

BACKGROUND

Full blood count is routinely performed in the evaluation of hypertensive patients. However, usefulness of leukocyte ratios in cardiovascular risk (CVR) assessment hasn't yet been proven in Cameroonians.

OBJECTIVE

Evaluate the contribution of leukocyte ratios in CVR assessment of non-diabetic hypertensive adults.

METHODOLOGY

We carried out a cross sectional study including non-diabetic hypertensive patients followed up at the cardiology unit of the Yaoundé Central Hospital from November to June 2022. We collected relevant clinical data with a pre-established questionnaire and blood samples from each patient for different biological analyses. The spearman correlation test was used to assess on the one hand the relationship between leukocyte ratios, highly sensitive CRP and the WHO 2019 risk score as our primary end point, and on the other hand between leukocyte indices and the other risk estimators as our secondary outcome. The significant threshold level was set as 0.05.

RESULTS

We included 165 participants (102 females) with a mean age of 57.6 (10.4) years. The median duration of hypertension since diagnosis was 7 years and only 27% of participants on treatment had a controlled blood pressure. There was no significant correlation between leukocyte ratios and the WHO 2019 risk score. Highly sensitive CRP and the atherogenic index of plasma were significantly correlated respectively with the granulocyte to lymphocyte ratio (rho = 0.18, p = 0.03) and the eosinophil to lymphocyte ratio (rho = 0.28, p = 0.01). There exists a weak positive association between the granulocyte to lymphocyte ratio and the Reynolds risk score.

CONCLUSION

Leukocyte ratios are not useful for CVR assessment in hypertensive Cameroonians with respect to the WHO 2019 risk score. Prospective studies are needed to assess their usefulness in combination with conventional risk factors to improve prediction of cardiovascular events.

Using an innovative family-centered evidence toolkit to improve the livelihood of people with disabilities in Bamenda (Cameroon): a mixed-method study

Background

Most of the disability-related scholarly literature focuses on high-income countries, whereas there is a lack of data concerning challenges (barriers and obstacles) and opportunities (participatory research and community engagement) in the Global South. Moreover, many frameworks for interventions for people with disabilities (PWDs) have been designed for resource-rich contexts, and little is known about their translatability to low- and middle-income countries (LMICs).

Objective

The main objective of this study was to design and pilot an interventional approach based on an innovative framework aimed at improving the livelihood of PWDs in LMICs.

Methodology

The present mixed-method study was conducted in Bamenda, North-West Region of Cameroon, through an intervention of household visits by community health workers using innovation and best practices informed by a systematic literature review and embedded into an evidence toolkit called the eBASE Family-Centered Evidence Toolkit for Disabilities (EFCETD), adapted from the WHO matrix and consisting of 43 questions across five categories (health, education, social wellbeing, empowerment, and livelihood). Out of 56 PWDs identified, 30 were randomly sampled, with an attrition of four participants. Three datasets (baseline, qualitative, and quantitative) were collected. The Washington Group tool, exploring the type of disability, gender, how long one has had the disability, their facility situation coupled with their coping strategies, and the context of livelihood, was used to design the questionnaire for baseline data collection. Qualitative data were collected through key informant interviews and focus group discussions analyzed with MAXQDA, while quantitative data were collected through the EFCETD and analyzed by means of descriptive statistics.

Results

In total, 69.2% of PWDs were female individuals. Many PWDs were aged 10-20 years (57% of the sample size). Physical/motor disability was the most common type of disability recorded (84.6%). The mean percentile for education increased from 29.9% during the first visit to 70.2% during the last visit, while the mean percentile for health increased from 65.4 to 78.7% and the mean percentile for social wellbeing moved from 73.1 to 84.9%. The livelihood and empowerment standards increased from 16.3 to 37.2% and from 27.7 to 65.8%, respectively. Overall, the temporal trend was statistically significant (F = 35.11, p < 0.0001). The adjusted score increased from the baseline value of 45.02 ± 2.38 to 61.07 ± 2.25, 65.24 ± 2.67, and 68.46 ± 2.78, at 4, 8, and 12 months, respectively. Compared to the baseline, all timepoints were significantly different, indicating a significant impact of the intervention, which became stable after 4 months and was preserved until 12 months.

Conclusion

PWDs faced many endeavors for sustainability and challenges resulting from a lack of inclusive policies and practices, leading to their exclusion from education, employment, and healthcare. Using implementation science approaches could bridge the gap and make policies and practices more effective.

Predictive values of ultrasound characters associated with malignant thyroid nodules in Yaoundé: a cross-sectional study

Introduction

most ultrasound criteria are defined in developed countries and commonly used in practice to assess the malignancy risk of thyroid nodules. This practice does not take into consideration some aspects of our context as delay of consultation and insufficient iodine intake. The objective of this study was to determine the predictive values of ultrasound characters associated with malignant thyroid nodules in our environment.

Methods

we conducted a cross-sectional, prospective, and analytical study in three hospitals in Yaoundé over a six-month period in 2022. Our sample consisted of thyroid nodules with ultrasound, cytopathological, and histopathological data. The ultrasound characters and histology status of category III thyroid nodules and higher in Bethesda score were analysed in univariate and multivariate statistics to determine their predictive values.

Results

eighty-nine nodules were obtained according to our inclusion criteria. The sex ratio was 0.46 and the average age of the patients was 46 years (IQR=42-59). The cancer prevalence in our sample was 22.47%. On ultrasound assessment, the characters associated to malignant histology (p<0.05) were nodules count, echogenicity, echostructure, presence or absence of microcalcifications, margins, and type of vascularization. Positive predictive values ranged from 26.15 to 57.14%, while negative predictive values ranged from 12.5 to 33.3%.

Conclusion

taken alone, the ultrasound characters of suspected thyroid nodules have poor predictive values. There was a high variability in sensitivity but that was generally good (60-95%) while specificity was low. The prediction of malignant thyroid nodules is correlated with the association of at least two ultrasound criteria supported by clinical arguments.

Factors influencing cervical cancer re-screening in a semi-rural health district of Cameroon: a cohort study

BACKGROUND

Screening participation at recommended intervals is a crucial component of cervical cancer prevention effectiveness. However, little is known regarding the rate of re-screening in a Sub-Saharan context. This study aimed to estimate the re-screening rate of women in a semi-rural after an initial HPV-based screening and identify factors that influence adherence.

METHODS

This cohort study at the Annex Regional Hospital of Dschang enrolled women screened for cervical cancer over 5 years ago and due for re-screening. Women who initially tested HPV-positive (n = 132) and a random sample of HPV-negative women (n = 220) participated in a telephone survey between October 2021 and March 2022 to assess re-screening participation and reasons. Sociodemographic factors were collected, and associations with rescreening were evaluated.

RESULTS

A total of 352 participants aged under 50 years (mean age 37.4 years) were contacted, and 203 (58.0%) completed the survey. The proportion of women who complied with the screening recommendation was 34.0% (95% CI 27.5% - 40.5%), The weighted re-screening proportion was 28.4%. Age, marital status, education level, type of employment, and place of residence were not associated with the rate of re-screening. Main reported barriers to re-screening were lack of information (39.0%), forgetfulness (39.0%), and impression of being in good health (30.0%). Women who remembered the recommended screening interval were 2 to 3 times more likely to undergo re-screening (aOR (adjusted odds ratio) = 2.3 [1.2-4.4], p = 0.013). Human papilloma virus- positive status at the initial screening was also associated with the re-screening((aOR) (95% CI): 3.4 (1.8-6.5).

CONCLUSION

Following an initial Human Papilloma Virus-based screening campaign in the West Region of Cameroon, one third of women adhered to re-screening within the recommended timeframe. Existing screening strategies would benefit from developing better information approaches to reinforce the importance of repeated cervical cancer screening.

Clothianidin-resistant Anopheles gambiae adult mosquitoes from Yaoundé, Cameroon, display reduced susceptibility to SumiShield® 50WG, a neonicotinoid formulation for indoor residual spraying

BACKGROUND

Chronic exposure of mosquito larvae to pesticide residues and cross-resistance mechanisms are major drivers of tolerance to insecticides used for vector control. This presents a concern for the efficacy of clothianidin, an agricultural neonicotinoid prequalified for Indoor Residual Spraying (IRS).

METHODS

Using standard bioassays, we tested if reduced susceptibility to clothianidin can affect the efficacy of SumiShield® 50WG, one of four new IRS formulations containing clothianidin. We simultaneously monitored susceptibility to clothianidin and to SumiShield 50WG, testing adults of Anopheles gambiae, An. coluzzii and Culex sp sampled from urban, suburban and agricultural areas of Yaoundé, Cameroon.

RESULTS

We found that in this geographic area, the level of susceptibility to the active ingredient predicted the efficacy of SumiShield 50WG. This formulation was very potent against populations that reached 100% mortality within 72 h of exposure to a discriminating concentration of clothianidin. By contrast, mortality leveled off at 75.4 ± 3.5% within 7 days of exposure to SumiShield 50WG in An. gambiae adults collected from a farm where the spraying of the two neonicotinoids acetamiprid and imidacloprid for crop protection is likely driving resistance to clothianidin.

CONCLUSIONS

Despite the relatively small geographic extend of the study, the findings suggest that cross-resistance may impact the efficacy of some new IRS formulations and that alternative compounds could be prioritized in areas where neonicotinoid resistance is emerging.

Influence of tides on the dissemination and related health risks of intestinal helminths along the Kribi beaches (Atlantic Coast, Southern Cameroon)

Kribi is a seaside town that welcomes thousands of tourists each year. However, the poor sanitation condition of its beaches along the Atlantic coast is not without risk for visitors. In this study, we used the formol-ether concentration technique to identify and quantify larvae or eggs of intestinal helminths in waters of three regularly visited Kribi beaches (Mpalla, Ngoyè, and Mboamanga). Results revealed that all identified larvae and eggs were cestodes (Hymenolepis nana) and nematodes (Strongyloides sp., Ascaris sp., Ancylostoma duodenale and Trichuris trichiura). All the helminth eggs and larvae showed high abundance at low tide during rainy seasons. Ancylostoma duodenale eggs, totally absent at Mpalla, were densely present at low tide at Ngoyè (301 ± 15 eggs/L). Trichuris trichiura eggs showed the lowest abundance (0 to 62 eggs/L) at all sites. Abiotic variables indicated that waters at the various beaches were basic (pH: 8.75-9.77), generally warmer (32.44°C at Mpalla in the Short Rainy Season), more oxygenated at low tide, and moderately mineralized at high tide. Positive and significant correlations were observed at Ngoyè at low tide between Strongyloides sp. larvae and dissolved oxygen (P ˂ 0.05); and between Ancylostoma duodenale eggs and temperature (P ˂ 0.05). The overall results indicated that the beaches studied are subjected to fecal pollution. This pollution is more accentuated during low tides than during high tides. Depending on tidal movements, swimmers risk exposure to helminth eggs and larvae known to be responsible for gastroenteritis.