18 research outputs found
Measuring Air Quality for Advocacy in Africa (MA3): Feasibility and Practicality of Longitudinal Ambient PM2.5 Measurement Using Low-Cost Sensors.
Ambient air pollution in urban cities in sub-Saharan Africa (SSA) is an important public health problem with models and limited monitoring data indicating high concentrations of pollutants such as fine particulate matter (PM2.5). On most global air quality index maps, however, information about ambient pollution from SSA is scarce. We evaluated the feasibility and practicality of longitudinal measurements of ambient PM2.5 using low-cost air quality sensors (Purple Air-II-SD) across thirteen locations in seven countries in SSA. Devices were used to gather data over a 30-day period with the aim of assessing the efficiency of its data recovery rate and identifying challenges experienced by users in each location. The median data recovery rate was 94% (range: 72% to 100%). The mean 24 h concentration measured across all sites was 38 µg/m3 with the highest PM2.5 period average concentration of 91 µg/m3 measured in Kampala, Uganda and lowest concentrations of 15 µg/m3 measured in Faraja, The Gambia. Kampala in Uganda and Nnewi in Nigeria recorded the longest periods with concentrations >250µg/m3. Power outages, SD memory card issues, internet connectivity problems and device safety concerns were important challenges experienced when using Purple Air-II-SD sensors. Despite some operational challenges, this study demonstrated that it is reasonably practicable and feasible to establish a network of low-cost devices to provide data on local PM2.5 concentrations in SSA countries. Such data are crucially needed to raise public, societal and policymaker awareness about air pollution across SSA
Non-communicable airway disease and air pollution in three African Countries: Benin, Cameroon and The Gambia
Air pollution exposure can increase the risk of development and exacerbation of chronic airway disease (CAD). We set out to assess CAD patients in Benin, Cameroon and The Gambia and to compare their measured exposures to air pollution.
We recruited patients with a diagnosis of CAD from four clinics in the three countries. We collected epidemiological, spirometric and home air pollution data.
Of the 98 adults recruited, 56 were men; the mean age was 51.6 years (standard deviation ±17.5). Most (69%) patients resided in cities and ever smoking was highest in Cameroon (23.0%). Cough, wheeze and shortness of breath were reported across the countries. A diagnosis of asthma was present in 74.0%; 16.3% had chronic obstructive pulmonary disease and 4.1% had chronic bronchitis. Prevalence of airflow obstruction was respectively 77.1%, 54.0% and 64.0% in Benin, Cameroon, and Gambia. Across the sites, 18.0% reported >5 exacerbations. The median home particulate matter less than 2.5 μm in diameter (PM2.5) was respectively 13.0 μg/m3, 5.0 μg/m3 and 4.4 μg/m3. The median home carbon monoxide (CO) exposures were respectively 1.6 parts per million (ppm), 0.3 ppm and 0.4 ppm. Home PM2.5 differed significantly between the three countries (P < 0.001) while home CO did not.
Based on these results, preventive programmes should focus on ensuring proper spirometric diagnosis, good disease control and reduction in air pollution exposure
Spirometry Abnormalities and Its Associated Factors Among Primary School Children in a Nigerian City.
BACKGROUND: There is paucity of data on objectively measured lung function abnormalities in Nigerian children using diagnostic testing methods such as spirometry. Such assessments could prompt early diagnosis and therapeutic interventions. METHODS: This was a cross sectional study among children aged 6 to 12 years in South-Eastern Nigeria. We selected participants from one school using a multistage stratified random sampling technique. A structured respiratory questionnaire was administered to obtain necessary data. The lung functions of the children were measured by spirometry. We used Lower Limits of Normal (LLN) based on GLI reference equations for African-American and mixed ethnicities to define abnormal spirometry. We studied the association between the exposures and lung function using logistic regression/chi-squared tests. RESULTS: A total of 145 children performed acceptable and repeatable tests. There were 73 males (50.3%), mean age of 9.13 years (+1.5) and age range 6 to 12 years. Frequency of respiratory symptoms was cough- 64 (44.1%) and wheeze in 19 (13.1%). Using GLI for African-Americans, fifty-five (37.9%) children had abnormal spirometryobstructive pattern in 40 (27.6%) and restrictive pattern in 15 (10.3%). The two references showed significant differences in interpretation of abnormality (χ2 = 72.86; P < .001). Respiratory symptom-wheeze was an independent determinant of abnormal lung function in this population.(OR = 0.31; 95%CI: 0.10-0.94; P = .04). CONCLUSION: There is a high burden of respiratory symptoms and abnormal spirometry among these children. The need for objective evaluation of lung function especially for children with respiratory symptoms is evident
Reliability of Rapid Diagnostic Tests in the diagnosis of malaria amongst children in two communities in South West Nigeria
Patients with presumed tuberculosis in sub-Saharan Africa that are not diagnosed with tuberculosis: a systematic review and meta-analysis.
BACKGROUND: Many patients in sub-Saharan Africa whom a diagnosis of tuberculosis is considered are subsequently not diagnosed with tuberculosis. The proportion of patients this represents, and their alternative diagnoses, have not previously been systematically reviewed. METHODS: We searched four databases from inception to 27 April 2020, without language restrictions. We included all adult pulmonary tuberculosis diagnostic studies from sub-Saharan Africa, excluding case series and inpatient studies. We extracted the proportion of patients with presumed tuberculosis subsequently not diagnosed with tuberculosis and any alternative diagnoses received. We conducted a random effects meta-analysis to obtain pooled estimates stratified by passive and active case finding. RESULTS: Our search identified 1799 studies, of which 18 studies (2002-2019) with 14 527 participants from 10 African countries were included. The proportion of patients with presumed tuberculosis subsequently not diagnosed with tuberculosis was 48.5% (95% CI 39.0 to 58.0) in passive and 92.8% (95% CI 85.0 to 96.7) in active case-finding studies. This proportion increased with declining numbers of clinically diagnosed tuberculosis cases. A history of tuberculosis was documented in 55% of studies, with just five out of 18 reporting any alternative diagnoses. DISCUSSION: Nearly half of all patients with presumed tuberculosis in sub-Saharan Africa do not have a final diagnosis of active tuberculosis. This proportion may be higher when active case-finding strategies are used. Little is known about the healthcare needs of these patients. Research is required to better characterise these patient populations and plan health system solutions that meet their needs. PROSPERO REGISTRATION NUMBER: CRD42018100004
Intense and Mild First Epidemic Wave of Coronavirus Disease, The Gambia.
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic is evolving differently in Africa than in other regions. Africa has lower SARS-CoV-2 transmission rates and milder clinical manifestations. Detailed SARS-CoV-2 epidemiologic data are needed in Africa. We used publicly available data to calculate SARS-CoV-2 infections per 1,000 persons in The Gambia. We evaluated transmission rates among 1,366 employees of the Medical Research Council Unit The Gambia (MRCG), where systematic surveillance of symptomatic cases and contact tracing were implemented. By September 30, 2020, The Gambia had identified 3,579 SARS-CoV-2 cases, including 115 deaths; 67% of cases were identified in August. Among infections, MRCG staff accounted for 191 cases; all were asymptomatic or mild. The cumulative incidence rate among nonclinical MRCG staff was 124 infections/1,000 persons, which is >80-fold higher than estimates of diagnosed cases among the population. Systematic surveillance and seroepidemiologic surveys are needed to clarify the extent of SARS-CoV-2 transmission in Africa
Non-communicable airway disease and air pollution exposure in sub-Saharan Africa
Background: Non-communicable airway diseases are public health problems and a cause of premature mortality globally: chronic obstructive pulmonary disease (COPD) accounts for 3.2 million deaths while asthma causes 445,000 deaths annually. Over 90% of the world’s population are exposed to air pollution daily. These two important and interplaying issues unfortunately do not get the needed attention from many health systems. This PhD sought tcontribute to non-communicable disease (NCD) control in sub-Saharan Africa (sSA) by generating novel data in chronic airway disease in three West African countries, as well as ambient air pollution level data in eight countries across sSA.
Methodology: Overall approaches used were: (a) Systematic review and meta-analysis of 17,566 adults with COPD in sSA: Prevalence and risk factors, (b) Pilot case-control study of the air pollution exposure-PM2.5 , CO and exhaled CO of 50 adult asthma and COPD patients and 50 age and sex-matched controls in The Gambia, with comparison of the cases with those obtained from Benin Republic (35 adults) and Cameroon (13 adults), (c) Longitudinal ground level ambient fine particulate matter 2.5 microns or less (PM2.5) measurement from eight sSA countries over one year. Data entry and formatting was done using microsoft excel while data management and analysis was done with R-studio. Descriptive and inferential statistical methods were applied as needed. Mixed effects model meta-analysis, conditional regression for the cases and controls, linear regression conducted for risk factors, and longitudinal data analysis were the main statistical methods used.
Results: COPD pooled prevalence in sub-Saharan Africa is 8% (CI 6-11%). This increases with age and smoking exposure. The Odds ratio of current smoking versus never smoking on COPD prevalence is 2.20 (CI 1.62-2.99).
The mean annual PM2.5 levels in all the 15 urban sites across the eight sSA countries were higher than the World Health Organization (WHO) recommended annual limit of 5µg/m3. Diurnal variation was observed across all sites with two daily PM2.5 peaks at 6:00 and 18:00 local time. The main challenges of use of low-cost sensors for longitudinal particulate matter measurement were power issues, internet connectivity and SD memory card issues.
Chronic Airway Disease (CAD) patients in The Gambia are likely to present with poorly controlled asthma or COPD with at least moderate effect on the person, significant exposure to second hand smoke (26%), personal PM2.5, burning refuse and occupational dust when compared with controls. Air pollution exposure was similar among both cases and controls.
Across Benin, Cameroon and The Gambia, respondents were mainly urban dwellers (69%), mean age of 51.6±17.5 years, with cough, wheeze and shortness of breath being the commonest symptoms.
Asthma was the commonest presenting CAD. Eighteen percent of the cohort reported 5 or more exacerbations in the past year. Ever smoking was highest in Cameroon (23%). Median home PM2.5 and
home CO were highest in Benin (13.0 µg/m3 : IQR-112.3 & 1.65µg/m3 : IQR-1.4 respectively.
Implications: sSA adult COPD prevalence and passive smoking exposure makes tobacco cessation counselling and anti-tobacco policies paramount. Urban African cities high air pollutant levels should engender citizen science and influence clean air policy enforcement. Clean fuel alternatives such as LPG, biogas and briquettes should be made available in much of sSA
Air quality management strategies in Africa: A scoping review of the content, context, co-benefits and unintended consequences.
One of the major consequences of Africa's rapid urbanisation is the worsening air pollution, especially in urban centres. However, existing societal challenges such as recovery from the COVID-19 pandemic, poverty, intensifying effects of climate change are making prioritisation of addressing air pollution harder. We undertook a scoping review of strategies developed and/or implemented in Africa to provide a repository to stakeholders as a reference that could be applied for various local contexts. The review includes strategies assessed for effectiveness in improving air quality and/or health outcomes, co-benefits of the strategies, potential collaborators, and pitfalls. An international multidisciplinary team convened to develop well-considered research themes and scope from a contextual lens relevant to the African continent. From the initial 18,684 search returns, additional 43 returns through reference chaining, contacting topic experts and policy makers, 65 studies and reports were included for final analysis. Three main strategy categories obtained from the review included technology (75%), policy (20%) and education/behavioural change (5%). Most strategies (83%) predominantly focused on household air pollution compared to outdoor air pollution (17%) yet the latter is increasing due to urbanisation. Mobility strategies were only 6% compared to household energy strategies (88%) yet motorised mobility has rapidly increased over recent decades. A cost effective way to tackle air pollution in African cities given the competing priorities could be by leveraging and adopting implemented strategies, collaborating with actors involved whilst considering local contextual factors. Lessons and best practices from early adopters/implementers can go a long way in identifying opportunities and mitigating potential barriers related to the air quality management strategies hence saving time on trying to "reinvent the wheel" and prevent pitfalls. We suggest collaboration of various stakeholders, such as policy makers, academia, businesses and communities in order to formulate strategies that are suitable and practical to various local contexts
Chronic Obstructive Pulmonary Disease (COPD) in sub-Saharan Africa: A Systematic Review and Meta-Analysis
Knowledge Attitude and Practice Regarding Obstructive Sleep Apnea among Medical Doctors in Southern Nigeria.
BACKGROUND
Despite the high global burden of Obstructive Sleep Apnea (OSA), doctors' knowledge of OSA was reported to be generally poor. Data on knowledge, attitude and practice of doctors regarding OSA are scarce in Africa. The only Nigerian study providing data on this included few participants and did not assess practice. We assessed the knowledge, attitude and practice of doctors regarding OSA in southern Nigeria with the aim of finding gaps in knowledge and practice.
METHODS
We sent out online survey monkey self-administered structured questionnaires to the WhatsApp numbers or e-mails of 1917 eligible medical doctors. The questionnaires were used to collect data on demography of the medical doctors, their professional history and knowledge of OSA symptoms; general facts, risks factors, and treatment regarding OSA; and their attitude and practice in relation to OSA.
RESULTS
Data from five hundred and eighty one respondents (mean age, 39.8 ± 8.7) were analyzed. Overall mean knowledge score was 25.3±6.3 (68.6±17.2 percent). The mean knowledge score of Internists, Family Physicians, General practitioners and Surgeons were 28.2±5.0; 25.0±6.9; and 24.5±5.8 and 24.2±6.7 respectively. Only 47% and 51% of the respondents respectively affirmed that hypertension and diabetes mellitus were associated with increased risk of OSA; and 7.2% referred suspected OSA patients for polysomnography.
CONCLUSION
The level of knowledge of OSA among participating doctors was poor. Most of them had the right attitude to OSA but their practice and care of OSA patients was suboptimal. We suggest improvement in care through education and provision of diagnostic and treatment facilities