Jobert Richie N Nansseu

Sero-epidemiology of human immunodeficiency virus, hepatitis B and C viruses, and syphilis infections among first-time blood donors in Edea, Cameroon

BACKGROUND Blood safety remains an issue of major concern in transfusion medicine in sub-Saharan Africa. Blood-borne agents such as the human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV), and Treponema pallidum are among the greatest threats to blood safety for the recipient. This study aimed to determine the seroprevalence and risk factors of HIV, HCV, HBV, and syphilis infections among first-time blood donors at the new hospital-based blood bank in Edéa, Cameroon. METHODS We carried out a retrospective analysis of blood donor data recorded between December 2011 and May 2012 at the blood bank of the Edéa Regional Hospital. Antibodies to HIV types 1 and 2 were screened with the Determine and ImmunoComb tests. Hepatitis B surface antigen and antibodies to HCV were detected using DIASpot test strips. Syphilis was diagnosed using the Venereal Disease Research Laboratory (VDRL) test and the Treponema pallidum hemagglutination assay (TPHA). RESULTS A total of 543 blood donors were included, among whom 349 (64.3%) were family replacement donors. One hundred and fifteen donors (21.2%) were infected with at least one pathogen. The overall seroprevalence rates of HIV, HBV, HCV, and syphilis were 4.1%, 10.1%, 4.8%, and 5.7%, respectively. We found a total of 26 dual infections. The most common combinations were HBV-HCV and HBV-HIV. There was a significant association between HIV and HBV infections (adjusted odds ratio (aOR) 3.46, 95% CI 1.29-9.39; p=0.014), and between HBV and HCV infections (aOR 2.81, 95% CI 1.02-10.12; p=0.036). Compared to voluntary donors, family replacement donors were significantly more infected by at least one screened pathogen (aOR 1.81, 95% CI 1.14-2.88; p=0.013), and more infected specifically by HIV (aOR 3.66, 95% CI 1.07-12.55; p=0.039) and syphilis (aOR 2.81, 95% CI 1.05-7.46; p=0.039). CONCLUSIONS Our findings indicate that blood safety remains a major problem in Cameroon where hospital-based blood banks and family replacement donors are predominant. There is an urgent need for a national blood transfusion program in Cameroon that will establish a nationally coordinated blood transfusion service based on the principles of voluntary regular non-remunerated blood donation.

Access to Diagnostic Tests and Essential Medicines for Cardiovascular Diseases and Diabetes Care: Cost, Availability and Affordability in the West Region of Cameroon

Objective To assess the availability and affordability of medicines and routine tests for cardiovascular disease (CVD) and diabetes in the West region of Cameroon, a low-income setting. Methods A survey was conducted on the availability and cost of twelve routine tests and twenty medicines for CVD and diabetes in eight health districts (four urban and four rural) covering over 60% of the population of the region (1.8 million). We analyzed the percentage of tests and medicines available, the median price against the international reference price (median price ratio) for the medicines, and affordability in terms of the number of days’ wages it would cost the lowest-paid unskilled government worker for initial investigation tests and procurement for one month of treatment. Results The availability of tests varied between 10% for the ECG to 100% for the fasting blood sugar. The average cost for the initial investigation using the minimum tests cost 29.76 days’ wages. The availability of medicines varied from 36.4% to 59.1% in urban and from 9.1% to 50% in rural settings. Only metformin and benzathine-benzylpenicilline had a median price ratio of ≤1.5, with statins being largely unaffordable (at least 30.51 days’ wages). One month of combination treatment for coronary heart disease costs at least 40.87 days’ wages. Conclusion The investigation and management of patients with medium-to-high cardiovascular risk remains largely unavailable and unaffordable in this setting. An effective non-communicable disease program should lay emphasis on primary prevention, and improve affordable access to essential medicines in public outlets.

What is the best strategy for the prevention of transfusion-transmitted malaria in sub-Saharan African countries where malaria is endemic?

The transmission of malaria by blood transfusion was one of the first recorded incidents of transfusion-transmitted infections (TTIs). Although the World Health Organization (WHO) recommends that blood for transfusion should be screened for TTIs, malaria screening is not performed in most malaria-endemic countries in sub-Saharan Africa (SSA). The transfusion of infected red blood cells may lead to severe post-transfusion clinical manifestations of malaria, which could be rapidly fatal. Ensuring that blood supply in endemic countries is free from malaria is highly problematical, as most of the donors may potentially harbour low levels of malaria parasites. Pre-transfusion screening within endemic settings has been identified as a cost-effective option for prevention of transfusion-transmitted malaria (TTM). But currently, there is no screening method that is practical, affordable and suitably sensitive for use by blood banks in SSA. Even if this method was available, rejection of malaria-positive donors would considerably jeopardize the blood supply and increase morbidity and mortality, especially among pregnant women and children who top the scale of blood transfusion users in SSA. In this context, the systematic prophylaxis of recipients with anti-malarials could constitute a good alternative, as it prevents any deferral of donor units as well as the occurrence of TTM. With the on-going programme, namely the Affordable Medicine Facility - Malaria, there is an increase in the availability of low-priced artemisinin-based combination therapy that can be used for systematic prophylaxis. It appears nonetheless an urgent need to conduct cost-benefit studies in order to evaluate each of the TTM preventive methods. This approach could permit the design and implementation of an evidence-based measure of TTM prevention in SSA, advocating thereby its widespread use in the region.

Low Sodium and High Potassium Intake for Cardiovascular Prevention: Evidence Revisited With Emphasis on Challenges in Sub-Saharan Africa

Reduction in dietary salt intake and increase in potassium intake can make a major contribution to the prevention and control of hypertension and consequential cardiovascular disease, especially in sub‐Saharan Africa (SSA) where prevalence rates are highest. African populations are going through a westernization of their traditional eating patterns, with a shift towards a US/Western‐style diet, which contains an excessive amount of salt. Currently, the mean sodium intake in SSA populations is far above the recommended daily allowance. Besides, potassium intake is low, and, particularly, the supply of fruits and vegetables that are important sources of potassium is insufficient to meet current and growing population needs in SSA countries. Context‐relevant strategies are needed for population‐wide sodium intake reduction and increase in potassium intake.

Hypertension prevalence, incidence and risk factors among children and adolescents in Africa: a systematic review and meta-analysis protocol

Introduction The African adult population is facing a growing epidemic of hypertension. Establishment of accurate epidemiological data on hypertension in African children and adolescents may have important implications for hypertension preventive strategies in Africa. Methods and analysis This systematic review and meta-analysis will follow the MOOSE Guidelines. Relevant abstracts published in English/French from 1 January 1985 to 31 July 2015 will be searched in PubMed, Google Scholar and Online African journals. Full texts of eligible studies will then be accessed through PubMed, Google Scholar, HINARI and the respective journals’ websites. Relevant unpublished papers and conference proceedings will also be checked. Data will be analysed using R statistical software. The study-specific estimates will be pooled through a random-effects meta-analysis model to obtain an overall summary estimate of the prevalence/incidence of hypertension across studies. Also, we will assess the association between risk factors and hypertension. Heterogeneity of studies will be evaluated by the χ2 test on Cochranes Q statistic. Funnel plots analysis and Eggers test will be done to detect publication bias. Results will be presented by geographic region (central, eastern, northern, southern and western Africa). A p value less than 0.05 will be considered significant for factors that predicted hypertension. Ethics and dissemination The current study is based on published data, and thus ethical approval is not required. This systematic review and meta-analysis is expected to serve as input for designing early life preventive and control strategies, and as a guide for future research based on existing gaps. The final report of the systematic review in the form of a scientific paper will be published in peer-reviewed journals. Findings will further be presented at conferences and submitted to relevant health authorities. Trial registration number CRD42015019029.

Low hepatitis B vaccine uptake among surgical residents in Cameroon

Background Hepatitis B virus (HBV) infection is one of the most serious occupational hazards faced by healthcare workers. Surgical personnel are particularly at risk. HBV infection is preventable by vaccination, but no previous study has assessed HBV vaccination coverage among healthcare workers in Cameroon. We assessed knowledge of risk factors of HBV infection, awareness of HBV vaccine, and vaccination status of surgical residents in Cameroon. Methods A structured pretested questionnaire was administered to 49 of the 70 surgical residents in Cameroon during the 2011–2012 academic year. Results Since the beginning of their residency program, 28 (57.1%) had had at least one accidental exposure to blood, with a median of 2 (range 1 to 25) exposures. Most of them had a good knowledge of risk factors for HBV infection. Although 98.0% (n = 48) were aware of the HBV vaccine, and 89.8% (n = 44) knew that they were at high risk of infection, only 24.5% (n = 12) had received a full course of at least three doses of the vaccine. In addition, only 33.3% (4/12) underwent post-vaccination testing to confirm a good immunological response (and thus effective protection against HBV infection). Among the 53.1% (n = 28) who had never had any dose of HBV vaccine, the main reasons for not being vaccinated were lack of time (38.5%), lack of money to pay for vaccine (23.1%), and lack of sufficient information on the vaccine (19.2%). Only 20.4% (n = 10) had been sensitized by their training institutions about the importance of HBV vaccination. Conclusion There is a low HBV vaccine uptake among surgical residents in Cameroon. As part of occupational safety measures, complete HBV vaccination should be strongly recommended and offered to surgical trainees before the beginning of their training program.

Prevalence and incidence of dyslipidaemia among adults in Africa: a systematic review and meta-analysis protocol.

Introduction Cardiovascular disease (CVD) is the leading cause of death globally and disproportionately affects low-income and middle-income countries. Dyslipidaemia is an important modifiable risk factor for CVD. There are important knowledge gaps regarding the population levels of lipid variables and frequency of non-optimal levels in populations within Africa. We propose to conduct a systematic review to determine the prevalence and occurrence of dyslipidaemia in adult populations within countries in Africa. Methods and analysis We will perform a comprehensive search to identify all possible published and unpublished studies on the prevalence or incidence of dyslipidaemia in Africa reported from 1 January 1980, without language restriction. The scientific databases PubMed MEDLINE, EMBASE and ISI Web of Science will be searched, as well as Grey literature. Following study selection, full-text papers acquisition, and data extraction and synthesis, we will appraise the quality of studies and risk of bias, and assess heterogeneity. Prevalence/incidence data will be summarised by country and geographic regions and a meta-analysis will be conducted for variables defined identically across studies. Variance stabilising transformations will be applied as appropriate to the row data before meta-analysis. This systematic review will be reported according to the MOOSE Guidelines for Meta-Analyses and Systematic Reviews of Observational Studies. Ethics and dissemination The current study is based on published data and as such ethics consideration is not a requirement. This review is expected to provide relevant data to help in quantifying the magnitude of dyslipidaemia in African populations, to emphasise the need for appropriate prevention and control strategies, and to identify research gaps and remaining challenges. The final report of the systematic review in the form of a scientific paper will be published in peer-reviewed journals. Findings will further be presented at conferences and submitted to relevant health authorities. Trial registration number PROSPERO CRD42014015376.

Are the current recommendations for the use of aspirin in primary prevention of cardiovascular disease applicable in low-income countries?

Although evidence has accumulated that long-term aspirin therapy is beneficial in secondary prevention of cardiovascular disease (CVD), a lot of controversies persist regarding the benefit of aspirin use in primary prevention of CVD. In low-income countries (LIC) specifically, the decision to prescribe aspirin for primary CVD prevention is more problematic, as there is a dearth of evidence in this regard. Aspirin has been shown to have relative beneficial effects in preventing a first myocardial infarction, but not stroke. However, as stroke is the prevailing CVD in many LIC, especially in Africa, the benefit of aspirin in these settings is therefore questionable. Indeed, there is no published trial that has evaluated the benefits and risks of continuous aspirin therapy in populations of LIC. Furthermore, though cardiovascular risk assessment is crucial in decision-making for the use of aspirin in primary prevention of CVD, there are no risk assessment tools that have been validated in African populations. Studies are urgently warranted, to determine the usefulness of aspirin in primary prevention of CVD in low-income settings where the drug is highly available and affordable, as CVD is becoming the leading cause of deaths in LIC.

Global prevalence of diabetes mellitus in patients with tuberculosis: a systematic review and meta-analysis protocol

Introduction Diabetes mellitus (DM) is an important risk factor for active tuberculosis (TB), which also adversely affect TB treatment outcomes. The escalating global DM epidemic is fuelling the burden of TB and should therefore be a major target in the strategy for ending TB. This review aims to estimate the global prevalence of DM in patients with TB. Methods and analysis This systematic review will include cross-sectional, case–control or cohort studies of populations including patients diagnosed with TB that have reported the prevalence of DM using one of the fourth standard recommendations for screening and diagnosis. This protocol is written in accordance with recommendations from the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols 2015 statement. Relevant abstracts published in English/French from inception to 31 December 2016 will be searched in PubMed, Excerpta Medica Database and online journals. Two investigators will independently screen, select studies, extract data and assess the risk of bias in each study. The study-specific estimates will be pooled through a random-effects meta-analysis model to obtain an overall summary estimate of the prevalence of diabetes across the studies. Heterogeneity will be assessed, and we will pool studies judged to be clinically homogenous. On the other hand, statistical heterogeneity will be evaluated by the χ² test on Cochrane’s Q statistic. Funnel-plots analysis and Egger’s test will be used to investigate publication bias. Results will be presented by continent or geographic regions. Ethics and dissemination This study is based on published data. An ethical approval is therefore not required. This systematic review and meta-analysis is expected to inform healthcare providers as well as general population on the co-occurrence of DM and TB. The final report will be published as an original article in a peer-reviewed journal, and will also be presented at conferences and submitted to relevant health authorities. We also plan to update the review every 5 years. Protocolregistration number PROSPERO International Prospective Register of Systematic Reviews (CRD42016049901).

Insulin resistance and associated factors among HIV-infected patients in sub-Saharan Africa: a cross sectional study from Cameroon

Introduction: little is known on the magnitude and correlates of insulin resistance in HIV-infected people in Africa. We determined the prevalence of insulin resistance and investigated associated factors in HIV-infected adult Cameroonians. Methods: we conducted a cross-sectional studyat the Yaounde Central Hospital, Cameroon; during which we enrolled HIV-infected people aged 30 to 74 years with no previous history of cardiovascular disease. The homeostatic model assessment of insulin resistance (HOMA-IR) index served to assess insulin sensitivity with insulin resistance defined by values of 2.1 or higher. Results: we included 452 patients (20% men). Their mean age was 44.4 ± 9.8 years and 88.5% of them were on antiretroviral therapy (93.3% on first line regimen including Zidovudine, lamivudine and Efavirenz/Nevirapine). Of all participants, 28.5% were overweight, 19.5% had obesity and 2.0% had diabetes. The prevalence of insulin resistance was 47.3% without any difference between patients on ART and those ART-naive (48.5% vs. 38.5%; p = 0.480). Obesity was the only factor independently associated with insulin resistance (adjusted odds ratio: 2.28; 95% confidence interval: 1.10-4.72). Conclusion: insulin resistance is present in nearly half of HIV-infected patients in Cameroon despite a low prevalence rate of diabetes, and is associated with obesity.