Yellow fever from Angola and Congo: a storm gathers

In common with Zika, Chikungunya and Dengue, Yellow Fever (YF) is an arthropod-borne flavivirus. It is transmitted between humans and from monkeys by mosquitoes of the Aedes aegypti (its principal vector), haemogogus and albopictus varieties. Three cycles of transmission may occur: urban; sylvatic; and intermediate. Recently, sub-Saharan Africa has seen the resurgence of this neglected disease. The current YF outbreak in Angola began in December 2015 in the capital Luanda and by October 2016 there had been > 4300 suspected cases, with 376 deaths (case fatality rate = 8.8%). A total of 884 were laboratory confirmed but it is likely that case numbers may be seriously underestimated. YF has subsequently quickly spread to neighbouring Congo and further afield to Kenya and also China, this being of grave concern as this was a first introduction of YF to Asia. YF has recently hit Brazil, with 555 suspected cases and 107 deaths reported by the end of January 2017. Extremely rapid unplanned urban migration in Africa by non-immune rural populations to already densely populated cities, where high densities of mosquitoes co-exist with city dwellers in makeshift flimsy accommodation, poses a ready recipe for an epidemic of massive proportion. In such conditions, with enormously strained public services existing among the most needy and vulnerable populations, mosquito control programmes are nearly impossible. YF in Congo is a tempest barely restrained. However, it is one that can be controlled by focused and committed international collaboration, by intense and united political will and by the marriage of old and trusted techniques: a vaccine almost a century old and some of the most modern technologies available to man.

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Competing interests, clashing ideas and institutionalizing influence: insights into the political economy of malaria control from seven African countries

Health Policy and Planning ◽

10.1093/heapol/czaa166 ◽

2020 ◽

Author(s):

Justin Parkhurst ◽

Ludovica Ghilardi ◽

Jayne Webster ◽

Robert W Snow ◽

Caroline A Lynch

Keyword(s):

Decision Making ◽

Malaria Control ◽

Qualitative Interviews ◽

Sub Saharan Africa ◽

African Countries ◽

Health Community ◽

Control Programmes ◽

Control Decision ◽

Sub Saharan ◽

Economic Considerations

Abstract This article explores how malaria control in sub-Saharan Africa is shaped in important ways by political and economic considerations within the contexts of aid-recipient nations and the global health community. Malaria control is often assumed to be a technically driven exercise: the remit of public health experts and epidemiologists who utilize available data to select the most effective package of activities given available resources. Yet research conducted with national and international stakeholders shows how the realities of malaria control decision-making are often more nuanced. Hegemonic ideas and interests of global actors, as well as the national and global institutional arrangements through which malaria control is funded and implemented, can all influence how national actors respond to malaria. Results from qualitative interviews in seven malaria-endemic countries indicate that malaria decision-making is constrained or directed by multiple competing objectives, including a need to balance overarching global goals with local realities, as well as a need for National Malaria Control Programmes to manage and coordinate a range of non-state stakeholders who may divide up regions and tasks within countries. Finally, beyond the influence that political and economic concerns have over programmatic decisions and action, our analysis further finds that malaria control efforts have institutionalized systems, structures and processes that may have implications for local capacity development.

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Spectrum-Malaria: a user-friendly projection tool for health impact assessment and strategic planning by malaria control programmes in sub-Saharan Africa

Malaria Journal ◽

10.1186/s12936-017-1705-3 ◽

2017 ◽

Vol 16 (1) ◽

Cited By ~ 7

Author(s):

Matthew Hamilton ◽

Guy Mahiane ◽

Elric Werst ◽

Rachel Sanders ◽

Olivier Briët ◽

...

Keyword(s):

Strategic Planning ◽

Impact Assessment ◽

Malaria Control ◽

Health Impact Assessment ◽

Health Impact ◽

Sub Saharan Africa ◽

Control Programmes ◽

Sub Saharan ◽

User Friendly

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The seasonality of cholera in sub-Saharan Africa

10.1101/2021.11.23.21265642 ◽

2021 ◽

Author(s):

Javier Perez-Saez ◽

Justin Lessler ◽

Elizabeth C. Lee ◽

Francisco J. Luquero ◽

Espoir B. Malembaka ◽

...

Keyword(s):

Large Scale ◽

Task Force ◽

Case Fatality ◽

Sub Saharan Africa ◽

Health Concern ◽

National Differences ◽

Sub Saharan ◽

Eastern And Southern Africa ◽

Positive Correlations ◽

Gates Foundation

Background Cholera remains a major threat in Sub-Saharan Africa (SSA) where some of the highest case fatality risks are reported. Knowing in what months and where cholera tends to occur across the continent can aid in improving efforts to eliminate cholera as a public health concern; though largely due to lack of unified large-scale datasets, no continent-wide estimates exist. In this study we aim to estimate cholera seasonality across SSA. Methods We leverage the Global Task Force on Cholera Control (GTFCC) global cholera database with statistical models to synthesize data across spatial and temporal scale in order to infer the seasonality of excess suspected cholera occurrence in SSA. We developed a Bayesian statistical model to infer the monthly risk of excess cholera at the first and/or second administrative levels. Seasonality patterns were then grouped into spatial clusters. Finally, we studied the association between seasonality estimates and hydro-climatic variables. Findings The majority of studied countries (24/34) have seasonal patterns in excess cholera, corresponding to approximately 85% of the SSA population. Most countries (19/24) also had sub-national differences in seasonality patterns, with strong differences in seasonality strength between regions. Seasonality patterns clustered into two macro-regions (West Africa and the Sahel vs. Eastern and Southern Africa), which were composed of sub-regional clusters with varying degrees of seasonality. Exploratory association analysis found most consistent and positive correlations between cholera seasonality and precipitation, and to a lesser extent with temperature and flooding. Interpretation Widespread cholera seasonality in SSA offers opportunities for intervention planning. Further studies are needed to study the association between cholera and climate. Funding The NASA Applied Sciences Program and the Bill and Melinda Gates Foundation.

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Evaluating survey designs for targeting preventive chemotherapy against Schistosoma haematobium and Schistosoma mansoni across Sub-Saharan Africa: a geostatistical analysis and modelling study

10.21203/rs.3.rs-36950/v3 ◽

2020 ◽

Author(s):

Kimberly Fornace ◽

Claudio Fronterrè ◽

Fiona M Fleming ◽

Hope Simpson ◽

Honorat Zoure ◽

...

Keyword(s):

Cost Effectiveness ◽

Schistosoma Haematobium ◽

Sampling Strategy ◽

Sub Saharan Africa ◽

Spatial Distributions ◽

Preventive Chemotherapy ◽

School Based ◽

Control Programmes ◽

Sub Saharan ◽

Survey Designs

Abstract Background: Schistosomiasis control programmes primarily use school-based surveys to identify areas for mass drug administration of preventive chemotherapy. However, as the spatial distribution of schistosomiasis can be highly focal, transmission may not be detected by surveys implemented at districts or larger spatial units. Improved mapping strategies are required to accurately and cost-effectively target preventive chemotherapy to remaining foci across all possible spatial distributions of schistosomiasis. Methods: Here, we use geostatistical models to quantify the spatial heterogeneity of Schistosoma haematobium and S. mansoni across sub-Saharan Africa using the most comprehensive dataset available on school-based surveys. Applying this information to parameterise simulations, we assess the accuracy and cost of targeting alternative implementation unit sizes across the range of plausible schistosomiasis distributions. We evaluate the consequences of decisions based on survey designs implemented at district and subdistrict levels sampling different numbers of schools. Cost data were obtained from field surveys conducted across multiple countries and years, with cost effectiveness evaluated as the cost per correctly identified school. Results: Models identified marked differences in prevalence and spatial distributions between countries and species; however, results suggest implementing surveys at subdistrict level increase the accuracy of treatment classifications across most scenarios. While sampling intensively at the subdistrict level resulted in the highest classification accuracy, this sampling strategy resulted in the highest costs. Alternatively, sampling the same numbers of schools currently recommended at the district level but stratifying by subdistrict increased cost effectiveness.Conclusions: This study provides a new tool to evaluate schistosomiasis survey designs across a range of transmission settings. Results highlight the importance of considering spatial structure when designing sampling strategies, illustrating that a substantial proportion of children may be undertreated even when an implementation unit is correctly classified. Control programmes need to weigh the increased accuracy of more detailed mapping strategies against the survey costs and treatment priorities.

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Prescrição da Vacina Contra a Febre Amarela: Experiência do Centro de Vacinação Internacional do Agrupamento de Centros de Saúde Loures-Odivela

Acta Médica Portuguesa ◽

10.20344/amp.10309 ◽

2018 ◽

Vol 31 (12) ◽

pp. 724

Author(s):

Clarisse Martinho ◽

David Lopes ◽

Luciana Bastos ◽

Hugo Esteves

Keyword(s):

Yellow Fever ◽

Yellow Fever Virus ◽

Health Centre ◽

Travel Medicine ◽

Sub Saharan Africa ◽

World Health ◽

Yellow Fever Vaccine ◽

Travel Destination ◽

Vector Borne ◽

Sub Saharan

Introduction: Yellow fever is a vector-borne disease in sub-Saharan Africa and tropical South America regions which is preventable by an effective and safe vaccine. In some cases, it may cause serious adverse effects and should therefore be prescribed only to individuals at risk of exposure to the yellow fever virus or those traveling to countries requiring proof of vaccination. The aim of this study was to analyze the prescriptions of yellow fever vaccine, based on travel destination and type of referring consultation, according to the international recommendations of the World Health Organization.Material and Methods: The database of the International Vaccination Centre of the International Vaccination Centre of the Loures-Odivelas Health Centre Group was used to analyze data concerning the year of 2016. Travelers who were prescribed and administered the yellow fever vaccine were grouped based on travel destination and type of referring consultation (travelers’ medical consultations or non-specialist consultations).Results: A total of 517 yellow fever vaccines were administered, with the highest proportion in female (53%) and in individuals aged 40 - 49 years (20.7%). One hundred and thirteen (22.6%) of the 499 individuals with known-destinations were travelling to non-endemic/non-epidemic countries and a greater proportion of those were prescribed in non-specialist consultations (27.3%) than in travel medicine consultations (8.8%).Discussion/Conclusion: The highest percentage of yellow fever vaccines that were administered to individuals travelling to non-endemic/non-epidemic countries were prescribed in non-specialist consultations.

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Stroke burden in Guinea: Results from the Conakry Ignace Deen Hospital stroke registry

International Journal of Stroke ◽

10.1177/1747493019884521 ◽

2019 ◽

Vol 15 (6) ◽

pp. 666-667 ◽

Cited By ~ 1

Author(s):

F Abass Cisse ◽

C Damien ◽

M Haba ◽

ML Touré ◽

M Barry ◽

...

Keyword(s):

Case Fatality ◽

Sub Saharan Africa ◽

Stroke Registry ◽

Stroke Prevalence ◽

Sub Saharan

Sub-Saharan Africa has extremely high stroke prevalence and case fatality. Most Sub-Saharan African regions are uncharted in terms of stroke characteristics, epidemiology, and burden. We report here the results from the first stroke registry in Guinea.

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The national determinants of deforestation in sub-Saharan Africa

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2012.0405 ◽

2013 ◽

Vol 368 (1625) ◽

pp. 20120405 ◽

Cited By ~ 85

Author(s):

Thomas K. Rudel

Keyword(s):

Forest Cover ◽

Driving Forces ◽

National Level ◽

Congo Basin ◽

Sub Saharan Africa ◽

Small Scale ◽

Urban Migration ◽

Forest Cover Change ◽

Level Data ◽

Sub Saharan

For decades, the dynamics of tropical deforestation in sub-Saharan Africa (SSA) have defied easy explanation. The rates of deforestation have been lower than elsewhere in the tropics, and the driving forces evident in other places, government new land settlement schemes and industrialized agriculture, have largely been absent in SSA. The context and causes for African deforestation become clearer through an analysis of new, national-level data on forest cover change for SSA countries for the 2000–2005 period. The recent dynamic in SSA varies from dry to wet biomes. Deforestation occurred at faster rates in nations with predominantly dry forests. The wetter Congo basin countries had lower rates of deforestation, in part because tax receipts from oil and mineral industries in this region spurred rural to urban migration, declines in agriculture and increased imports of cereals from abroad. In this respect, the Congo basin countries may be experiencing an oil and mineral fuelled forest transition. Small farmers play a more important role in African deforestation than they do in southeast Asia and Latin America, in part because small-scale agriculture remains one of the few livelihoods open to rural peoples.

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ASSESSING AND ADDRESSING CLIMATE-INDUCED RISK IN SUB-SAHARAN RAINFED AGRICULTURE

Experimental Agriculture ◽

10.1017/s0014479711000019 ◽

2011 ◽

Vol 47 (2) ◽

pp. 179-184 ◽

Cited By ~ 25

Author(s):

P. J. M. COOPER ◽

R. COE

Keyword(s):

World Bank ◽

Sub Saharan Africa ◽

Poverty Traps ◽

Rainfed Agriculture ◽

Political Will ◽

Feed Production ◽

Food And Feed ◽

Sub Saharan ◽

To Come ◽

State Of Affairs

Rainfed agriculture in sub-Saharan Africa (SSA) is the mainstay of the continent's food and feed production. Nearly 90% of staple food and feed production comes from, and will continue to come from, rainfed agriculture (Rosegrant et al., 2002). In spite of this, investment in this vital production system, and hence its productivity, has stagnated. There are many complex and interrelated issues that contribute to this state of affairs. The outcomes of lack of investment and low production of rainfed agriculture reinforce each other leading to poverty traps and increased vulnerability of livelihoods to climatic and other shocks (World Bank, 2000). This has become well recognized and an emerging political will, both within and outside SSA, to support increased investment in rainfed agriculture appears to be gaining momentum (Sanchez et al, 2009).

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