21 research outputs found
Quality of fresh frozen tilapia from selected supermarkets in Malawi
Fish provides a major source of dietary animal protein to Malawi’s population. Majority of tilapia in supermarkets are of different origins and bought from different suppliers. Fish is highly perishable commodity and its quality degrades even in frozen form due to microbial activity. The quality of frozen tilapia (the most commonly traded and consumed fish in Malawi) sold in some reputable supermarkets in Malawi was determined. Fish were collected from nine (9) reputable supermarkets in three (3) regions of the country (north, central and south) and analysed in the laboratory for sensory quality, microbiological, chemical and proximate analyses. Sensory quality evaluation was performed following guidelines earlier developed for fresh tilapia (Oreochromis spp.) in Malawi. Differences and changes in the fish sensory quality were attributed to the effect of storage duration and conditions within the freezer compartment. Two types of bacteria namely, Salmonella spp. and Escherichia coliwere identified on the frozen tilapia, suggesting poor and unhygienic pre-handling. Despite the presence of bacteria on the fish and differences in sensory quality, the frozen tilapia were within the acceptable range for human consumption. Nutrient composition of frozen tilapia was high despite differences (p<0.05) in moisture, ash and crude fat. Fish from different origin were sold mixed in all supermarkets, poor handling along the fish market chain was identified as the major source of fish contamination. Mechanical damages were reminiscent of the effects of frozen storage. There is a need to establish optimum storage time for frozen tilapia in supermarkets to provide products with good quality in terms of sensory properties, nutrient content and safe microbial loads. 
Temporally consistent predominance and distribution of secondary malaria vectors in the Anopheles community of the upper Zambezi floodplain.
Regional optimisation of malaria vector control approaches requires detailed understanding both of the species composition of Anopheles mosquito communities, and how they vary over spatial and temporal scales. Knowledge of vector community dynamics is particularly important in settings where ecohydrological conditions fluctuate seasonally and inter-annually, such as the Barotse floodplain of the upper Zambezi river. DNA barcoding of anopheline larvae sampled in the 2019 wet season revealed the predominance of secondary vector species, with An. coustani comprising > 80% of sampled larvae and distributed ubiquitously across all ecological zones. Extensive larval sampling, plus a smaller survey of adult mosquitoes, identified geographic clusters of primary vectors, but represented only 2% of anopheline larvae. Comparisons with larval surveys in 2017/2018 and a contemporaneous independent 5-year dataset from adult trapping corroborated this paucity of primary vectors across years, and the consistent numerical dominance of An. coustani and other secondary vectors in both dry and wet seasons, despite substantial inter-annual variation in hydrological conditions. This marked temporal consistency of spatial distribution and anopheline community composition presents an opportunity to target predominant secondary vectors outdoors. Larval source management should be considered, alongside prevalent indoor-based approaches, amongst a diversification of vector control approaches to more effectively combat residual malaria transmission
COVID-19 in sub-Saharan Africa: impacts on vulnerable populations and sustaining home-grown solutions
© 2020, The Canadian Public Health Association. This commentary draws on sub-Saharan African health researchers’ accounts of their countries’ responses to control the spread of COVID-19, including social and health impacts, home-grown solutions, and gaps in knowledge. Limited human and material resources for infection control and lack of understanding or appreciation by the government of the realities of vulnerable populations have contributed to failed interventions to curb transmission, and further deepened inequalities. Some governments have adapted or limited lockdowns due to the negative impacts on livelihoods and taken specific measures to minimize the impact on the most vulnerable citizens. However, these measures may not reach the majority of the poor. Yet, African countries’ responses to COVID-19 have also included a range of innovations, including diversification of local businesses to produce personal protective equipment, disinfectants, test kits, etc., which may expand domestic manufacturing capabilities and deepen self-reliance. African and high-income governments, donors, non-governmental organizations, and businesses should work to strengthen existing health system capacity and back African-led business. Social scientific understandings of public perceptions, their interactions with COVID-19 control measures, and studies on promising clinical interventions are needed. However, a decolonizing response to COVID-19 must include explicit and meaningful commitments to sharing the power—the authority and resources—to study and endorse solutions
One Hundred Priority Questions for the Development of Sustainable Food Systems in Sub-Saharan Africa
Sub-Saharan Africa is facing an expected doubling of human population and tripling of food demand over the next quarter century, posing a range of severe environmental, political, and socio-economic challenges. In some cases, key Sustainable Development Goals (SDGs) are in direct conflict, raising difficult policy and funding decisions, particularly in relation to trade-offs between food production, social inequality, and ecosystem health. In this study, we used a horizon-scanning approach to identify 100 practical or research-focused questions that, if answered, would have the greatest positive impact on addressing these trade-offs and ensuring future productivity and resilience of food-production systems across sub-Saharan Africa. Through direct canvassing of opinions, we obtained 1339 questions from 331 experts based in 55 countries. We then used online voting and participatory workshops to produce a final list of 100 questions divided into 12 thematic sections spanning topics from gender inequality to technological adoption and climate change. Using data on the background of respondents, we show that perspectives and priorities can vary, but they are largely consistent across different professional and geographical contexts. We hope these questions provide a template for establishing new research directions and prioritising funding decisions in sub-Saharan Africa
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One hundred priority questions for the development of sustainable food systems in sub-Saharan Africa
Sub-Saharan Africa is facing an expected doubling of human population and tripling of food demand over the next quarter century, posing a range of severe environmental, political, and socio-economic challenges. In some cases, key Sustainable Development Goals (SDGs) are in direct conflict, raising difficult policy and funding decisions, particularly in relation to trade-offs between food production, social inequality, and ecosystem health. In this study, we used a horizon-scanning approach to identify 100 practical or research-focused questions that, if answered, would have the greatest positive impact on addressing these trade-offs and ensuring future productivity and resilience of food-production systems across sub-Saharan Africa. Through direct canvassing of opinions, we obtained 1339 questions from 331 experts based in 55 countries. We then used online voting and participatory workshops to produce a final list of 100 questions divided into 12 thematic sections spanning topics from gender inequality to technological adoption and climate change. Using data on the background of respondents, we show that perspectives and priorities can vary, but they are largely consistent across different professional and geographical contexts. We hope these questions provide a template for establishing new research directions and prioritising funding decisions in sub-Saharan Africa
Development and validation of quantitative PCR assays for HIV-associated cryptococcal meningitis in sub-Saharan Africa: a diagnostic accuracy study
Background: HIV-associated cryptococcal meningitis is the second leading cause of AIDS-related deaths, with a 10-week mortality rate of 25–30%. Fungal load assessed by colony-forming unit (CFU) counts is used as a prognostic marker and to monitor response to treatment in research studies. PCR-based assessment of fungal load could be quicker and less labour-intensive. We sought to design, optimise, and validate quantitative PCR (qPCR) assays for the detection, identification, and quantification of Cryptococcus infections in patients with cryptococcal meningitis in sub-Saharan Africa.
Methods:
We developed and validated species-specific qPCR assays based on DNA amplification of QSP1 (QSP1A specific to Cryptococcus neoformans, QSP1B/C specific to Cryptococcus deneoformans, and QSP1D specific to Cryptococcus gattii species) and a pan-Cryptococcus assay based on a multicopy 28S rRNA gene. This was a longitudinal study that validated the designed assays on cerebrospinal fluid (CSF) of 209 patients with cryptococcal meningitis at baseline (day 0) and during anti-fungal therapy (day 7 and day 14), from the AMBITION-cm trial in Botswana and Malawi (2018–21). Eligible patients were aged 18 years or older and presenting with a first case of cryptococcal meningitis.
Findings:
When compared with quantitative cryptococcal culture as the reference, the sensitivity of the 28S rRNA was 98·2% (95% CI 95·1–99·5) and of the QSP1 assay was 90·4% (85·2–94·0) in CSF at day 0. Quantification of the fungal load with QSP1 and 28S rRNA qPCR correlated with quantitative cryptococcal culture (R2=0·73 and R2=0·78, respectively). Both Botswana and Malawi had a predominant C neoformans prevalence of 67% (95% CI 55–75) and 68% (57–73), respectively, and lower C gattii rates of 21% (14–31) and 8% (4–14), respectively. We identified ten patients that, after 14 days of treatment, harboured viable but non-culturable yeasts based on QSP1 RNA detection (without any positive CFU in CSF culture).
Interpretation:
QSP1 and 28S rRNA assays are useful in identifying Cryptococcus species. qPCR results correlate well with baseline quantitative cryptococcal culture and show a similar decline in fungal load during induction therapy. These assays could be a faster alternative to quantitative cryptococcal culture to determine fungal load clearance. The clinical implications of the possible detection of viable but non-culturable cells in CSF during induction therapy remain unclear
Development and validation of quantitative PCR assays for HIV-associated cryptococcal meningitis in sub-Saharan Africa: a diagnostic accuracy study
Background:
HIV-associated cryptococcal meningitis is the second leading cause of AIDS-related deaths, with a 10-week mortality rate of 25–30%. Fungal load assessed by colony-forming unit (CFU) counts is used as a prognostic marker and to monitor response to treatment in research studies. PCR-based assessment of fungal load could be quicker and less labour-intensive. We sought to design, optimise, and validate quantitative PCR (qPCR) assays for the detection, identification, and quantification of Cryptococcus infections in patients with cryptococcal meningitis in sub-Saharan Africa.
Methods:
We developed and validated species-specific qPCR assays based on DNA amplification of QSP1 (QSP1A specific to Cryptococcus neoformans, QSP1B/C specific to Cryptococcus deneoformans, and QSP1D specific to Cryptococcus gattii species) and a pan-Cryptococcus assay based on a multicopy 28S rRNA gene. This was a longitudinal study that validated the designed assays on cerebrospinal fluid (CSF) of 209 patients with cryptococcal meningitis at baseline (day 0) and during anti-fungal therapy (day 7 and day 14), from the AMBITION-cm trial in Botswana and Malawi (2018–21). Eligible patients were aged 18 years or older and presenting with a first case of cryptococcal meningitis.
Findings:
When compared with quantitative cryptococcal culture as the reference, the sensitivity of the 28S rRNA was 98·2% (95% CI 95·1–99·5) and of the QSP1 assay was 90·4% (85·2–94·0) in CSF at day 0. Quantification of the fungal load with QSP1 and 28S rRNA qPCR correlated with quantitative cryptococcal culture (R2=0·73 and R2=0·78, respectively). Both Botswana and Malawi had a predominant C neoformans prevalence of 67% (95% CI 55–75) and 68% (57–73), respectively, and lower C gattii rates of 21% (14–31) and 8% (4–14), respectively. We identified ten patients that, after 14 days of treatment, harboured viable but non-culturable yeasts based on QSP1 RNA detection (without any positive CFU in CSF culture).
Interpretation:
QSP1 and 28S rRNA assays are useful in identifying Cryptococcus species. qPCR results correlate well with baseline quantitative cryptococcal culture and show a similar decline in fungal load during induction therapy. These assays could be a faster alternative to quantitative cryptococcal culture to determine fungal load clearance. The clinical implications of the possible detection of viable but non-culturable cells in CSF during induction therapy remain unclear.
Funding:
European and Developing Countries Clinical Trials Partnership; Swedish International Development Cooperation Agency; Wellcome Trust/UK Medical Research Council/UKAID Joint Global Health Trials; and UK National Institute for Health Research
Knowledge and perception about tuberculosis among children attending primary school in Ntcheu District, Malawi
Peter Nyasulu,1,3 Susan Kambale,2 Tobias Chirwa,3 Teye Umanah,3 Isaac Singini,4 Simon Sikwese,5 Hastings T Banda,6 Rhoda P Banda,7 Henry Chimbali,8 Bagrey Ngwira,9 Alister Munthali10 1Department of Public Health, School of Health Sciences, Monash University, Johannesburg, South Africa; 2World Health Organization, Country Office, Lilongwe, Malawi; 3School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa; 4Johns Hopkins Research Project, College of Medicine, University of Malawi, 5Pakachere Institute of Health and Development Communication, Blantyre, 6Research for Equity and Community Health (REACH) Trust, Lilongwe, 7National Tuberculosis Control Program, Community Health Sciences Unit, Ministry of Health, Lilongwe, 8Health Promotion Section, Ministry of Health, Lilongwe, 9Department of Community Health, College of Medicine, University of Malawi, Blantyre, 10Centre for Social Research, University of Malawi, Zomba, Malawi Background: Knowledge and perceptions about tuberculosis (TB) can influence care-seeking behavior and adherence to treatment. Previous studies in Malawi were conducted to assess knowledge and attitudes regarding TB in adults, with limited data on knowledge in children. Objectives: This study assessed knowledge and perceptions about TB in children aged 10–14 years attending primary school in Ntcheu District, Malawi. Design: A cross-sectional study was conducted in four primary schools in Ntcheu District. Data on knowledge and perception of TB were collected using a structured questionnaire. Pearson chi-square test was used to determine the association between socioeconomic factors and TB knowledge and perception. A P<0.05 was considered significant. Results: The study found that the learners had high knowledge regarding the cause, spread, and TB preventive measures. Almost 90% of learners knew that TB is caused by a germ, however, a lower proportion knew about TB symptoms ie, night sweats (49%) and enlarged cervical lymph nodes (40%). We found that 68% of learners did not know the duration of anti-TB treatment. No association was found between age, learners' grade, and knowledge (P>0.05). Conclusion: Lack of knowledge regarding TB and gaps identified, may be due to a deficiency in the content of the school curriculum or the availability of information, education, and communication materials. This is the first study to report on knowledge and perceptions of TB among primary school learners in Malawi. These results will inform the development of relevant information, education, and communication materials to enhance awareness about TB among school going children. Keywords: tuberculosis, knowledge, perceptions, health seeking, adherence, Malaw
Predictors of late virologic failure after initial successful suppression of HIV replication on efavirenz-based antiretroviral therapy
Background: Practical issues, including cost, hinder implementing virologic monitoring of patients on antiretroviral therapy (ART) in resource-limited settings. We evaluated factors that might guide monitoring frequency and efforts to prevent treatment failure after initial virologic suppression.
Methods: Participants were the 911 HIV-infected antiretroviral-naïve adults with CD4 count <300 cells/μL who started efavirenz-based ART in the international A5175/PEARLS trial and achieved HIV-1 RNA <1000 copies/mL at 24 weeks. Participant report of ART adherence was evaluated using a structured questionnaire in monthly interviews. Adherence and readily available clinical and laboratory measures were evaluated as predictors of late virologic failure (late VF: confirmed HIV-1 RNA ≥1000 copies/mL after 24 weeks).
Results: During median follow-up of 3.5 years, 82/911 participants (9%) experienced late VF. Of 516 participants reporting missed doses during the first 24 weeks of ART, 55 (11%) experienced late VF, compared with 27 (7%) of 395 participants reporting no missed doses (hazard ratio: 1.73; 95% CI: 1.08, 2.73). This difference persisted in multivariable analysis, in which lower pre-ART hemoglobin and absence of Grade ≥3 laboratory results prior to week 24 were also associated with higher risk of late VF.
Discussion: In this clinical trial, the late VF rate after successful suppression was very low. If achievable in routine clinical practice, virologic monitoring involving infrequent (e.g. annual) measurements might be considered; the implications of this for development of resistance need evaluating. Patients reporting missed doses early after ART initiation, despite achieving initial suppression, might require more frequent measurement and/or strategies for promoting adherence