Etude de l’effet rémanent de Mavi MNPV dans un champ de niébé

Le niébé est l’une des légumineuses alimentaires la plus importante dans toutes les régions de l’Afrique Sub-saharienne. L’objectif de ce travail était d’étudier l’effet rémanent de Mavi Multinucléo polyhedrovirus (Mavi MNPV) après la récolte du niébé au champ. Le champ a été traité 5 fois au biopesticide Mavi MNPV à la fréquence de sept jours. Deux semaines après la récolte, deux plants ainsi que les graines de chaque traitement sur chaque unité parcellaire ayant reçu les traitements de Mavi MNPV de 107, 108 et 109 virions/ml ont été collectés et amenés au laboratoire avec le substrat de développement de la plante (sable). Aucune des formulations issues des substrats sable, racines, feuilles, tiges et graines n’a affecté la mortalité des larves L2 et L3 de Maruca vitrata et aucune différence significative n’a été observée entre les traitements et le témoin. Quels que soient les traitements, le taux d’émergence des adultes est élevé ; ce qui signifie que la variation de la concentration de Mavi MNPV ne conditionne pas sa présence dans le sol, les tiges, les feuilles, les racines et les graines. Le biopesticide Mavi MNPV n’est pas persistant dans la nature.Mots clés : Niébé, Mavi MNPV, Maruca vitrata, Effet rémanent English Title: Study of the residual effect of Mavi MNPV in a cowpea field Cowpea is one of the most important food legumes in all regions of Sub-Saharan Africa. The objective of this research work was to study the persistence effect of Mavi Multinucleus polyhedrovirus (Mavi MNPV) after field harvest of the cowpea. The field was treated 5 times with Mavi MNPV biopesticide at seven days. Two weeks after harvest, two plants as well as the seeds from each treatment on each plot unit that received Mavi MNPV treatments of 107, 108 and 109 virions / ml were removed and brought to the laboratory with the plant development substrate (sand). None of the formulations from sand, root, leaf, stem and seed substrates did not affect the mortality of L2 and L3 larvae of Maruca vitrata and no significant difference was observed between treatments and control. Regardless of the treatments, the rate of emergence of adults is high; this means that the variation in the concentration of Mavi MNPV does not condition its presence in soil, stems, leaves, roots and seeds. Mavi MNPV biopesticide is not persistent in nature.Keywords: Cowpea, Mavi MNPV, Maruca vitrata, Residual effect.

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Unravelling the Perspectives of Day and Night Traders in Selected Markets within a Sub-Saharan African City with a Malaria Knowledge, Attitude and Practice Survey

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18073468 ◽

2021 ◽

Vol 18 (7) ◽

pp. 3468

Author(s):

Patience B. Tetteh-Quarcoo ◽

Nicholas T. K. D. Dayie ◽

Kevin Kofi Adutwum-Ofosu ◽

John Ahenkorah ◽

Emmanuel Afutu ◽

...

Keyword(s):

Cross Sectional Study ◽

Malaria Treatment ◽

Sub Saharan Africa ◽

African City ◽

Cross Sectional ◽

Attitudes And Practices ◽

Treatment Type ◽

Significant Difference ◽

High Knowledge ◽

Sub Saharan

Background: Malaria is still endemic in sub-Saharan Africa, with a high disease burden. Misconceptions about malaria contribute to poor attitudes and practices, further increasing the burden in endemic countries. Studies have examined the knowledge, attitudes, and practices (KAP) of malaria among different populations. However, there seems to be no available literature reporting on the perspectives of day and night market traders. To the best of our knowledge, this is the first report on malaria KAP with a focus on day and night market traders. Methods: A descriptive cross-sectional study involving day and night market traders in 10 selected markets within the Greater Accra Region of Ghana was carried out. Data were collected from consenting respondents using a structured questionnaire. Results: Of the 760 respondents (33.3% (n = 253) night and 66.7% (n = 507) day traders) interviewed, there was no significant difference between the day and night market traders in terms of malaria KAP. Although the market traders had an overall moderate knowledge (54.0% of the day traders and 56.5% of the night traders), misconceptions about malaria (especially that it could be caused by exposure to the sun) still existed among the traders. Moreover, the majority of the traders who demonstrated high knowledge (43.98%, n = 250) did not always take laboratory tests to confirm their suspicion, indicating poor attitude. Furthermore, the market traders’ choice of drug for malaria treatment (p = 0.001) and preferred malaria treatment type (orthodox or herbal) (p = 0.005) were significantly associated with their knowledge level. Conclusions: Despite the observation that no significant difference in KAP exists between day and night market traders, appropriate health education programs and interventions still need to be directed at misconceptions, poor attitudes, and poor practices revealed by this study. This will ultimately help in the prevention and control of malaria in Ghana, and globally.

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Control trial of porcine cysticercosis in Uganda using a combination of the TSOL18 vaccination and oxfendazole

Infectious Diseases of Poverty ◽

10.1186/s40249-021-00823-6 ◽

2021 ◽

Vol 10 (1) ◽

Author(s):

Zachary Nsadha ◽

Chris Rutebarika ◽

Chrisostom Ayebazibwe ◽

Bukenya Aloys ◽

M. Mwanja ◽

...

Keyword(s):

Taenia Solium ◽

Control Program ◽

Control Area ◽

Sub Saharan Africa ◽

Intermediate Hosts ◽

Porcine Cysticercosis ◽

Intervention Area ◽

Significant Difference ◽

Sub Saharan ◽

Village Communities

Abstract Background Neurocysticercosis caused by Taenia solium when the parasite lodges in the central nervous system, is an important cause of human seizures and mortality in sub-Saharan Africa. The parasite is prevalent in many regions of Uganda. Pigs are intermediate hosts for T. solium, and we evaluated a T. solium control program in pigs, involving vaccination of pigs with the TSOL18 vaccine and treatment with oxfendazole. Methods The study was conducted in two districts of Eastern Uganda involving the rural village communities of Bukedea (intervention area) and Kumi (control area) during 2016–2017. Seven hundred and thirty-four households were enrolled in the study. Pigs in the intervention area received intramuscular immunizations with TSOL18 (Cysvax™) and an oral medication with 30 mg/kg oxfendazole (Paranthic™) at approximately 3-monthly intervals for 18 months. Porcine cysticercosis was evaluated by post-mortem examination. At the beginning of the study, 111 pigs were examined. In an interim evaluation in the intervention area, 55 pigs were evaluated 12 months after starting the project. At the end of the study approximately 3 months after the final intervention, 55 pigs from the intervention area and 56 pigs from the control area were evaluated. Results The prevalence of porcine cysticercosis for the two sites was 16.2% at the beginning of the study (17.2% in the intervention area and 15.1% in the control area) with no statistically significant difference (P = 0.759) between the two study sites. Among the 110 animals assessed from the intervention site (55 at the interim evaluation and 55 at the final evaluation), no pig with viable T. solium cysts was found. There was a statistically significant difference between the prevalence at baseline (17.2%) and at the end of the study (0%) in the intervention area (P = 0.001) and a statistically significant difference between the intervention (0%) and control areas (5.4%) (P = 0.041) at the end of the study. Conclusions Three-monthly concurrent vaccination of pigs with the TSOL18 vaccine and medication with oxfendazole eliminated T. solium transmission by the animals involved in the study. Application of vaccination with medication in pigs has the potential to reduce transmission of T. solium in Uganda and other endemic countries.

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Inter-rater Variability in Malaria Microscopy at the LEKMA Hospital, Ghana

Journal of Parasitology Research ◽

10.1155/2020/8897337 ◽

2020 ◽

Vol 2020 ◽

pp. 1-6

Author(s):

Andrew Nii Adzei Bekoe ◽

Emmanuel Alote Allotey ◽

Elliot Elikplim Akorsu ◽

Albert Abaka-Yawson ◽

Samuel Adusei ◽

...

Keyword(s):

Sub Saharan Africa ◽

Medical Laboratory ◽

Rater Agreement ◽

Laboratory Personnel ◽

Parasite Count ◽

Laboratory Staff ◽

Significant Difference ◽

Expected Outcome ◽

Sub Saharan ◽

Group B

Background. Malaria remains a major cause of morbidity and mortality worldwide and particularly in sub-Saharan Africa where it is endemic. As such, it is important that a proper diagnosis is made before treatment is initiated. Malaria parasite count plays a key role in the diagnosis and management of malaria. Variations in ratings by laboratory personnel can impact negatively on the treatment regimen for malaria-infected patients. The study is thus aimed at evaluating and comparing the proficiency and parasitaemia counts by two different categories of laboratory staff at the LEKMA Hospital, Ghana. Materials and Methods. A total of 200 confirmed malaria-positive samples were used in the study. Six thick and thin films were prepared from each sample and uniquely labelled. Two of the six slides were given to two WHO-accredited malaria microscopists to examine and report their respective parasite count/μl ( parasite count / WBC × 8000 ). These were used as the reference for the two categories of laboratory staffs: rater A being diploma holders (Technical Officers referred to as untrained rater) and rater B being degree holders (Medical Laboratory Scientist referred to as trained rater) at the LEKMA Hospital. Results. In comparison to the expected outcome, the parasite count by the rater group A (190 (151-239)]) and the rater group B (177 (140-224)) demonstrated significant positive correlation ( r = 0.995 , p < 0.0001 vs. r = 0.995 , p < 0.0001 , respectively) with the expected outcome in the cases of heavy parasitaemia. A statistically significant difference ( p < 0.05 ) between counts by the different raters in low parasitemia was observed in this study. A persistent nosedive inter-rater agreement from k = 0.82 to k = 0.40 with increasing density cutoff was observed in this study. Conclusion. The study observed that the degree of inter-rater agreement of parasite density count by various categories of laboratory personnel is almost perfect. However, the parasite count between raters varied significantly with very low levels of parasitemia but better correlated with heavy parasitemia.

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An afebrile heartwater-like syndrome in goats

Journal of the South African Veterinary Association ◽

10.4102/jsava.v84i1.955 ◽

2013 ◽

Vol 84 (1) ◽

Author(s):

Rhoda Leask ◽

Kenneth P. Pettey ◽

Gareth F. Bath

Keyword(s):

Clinical Signs ◽

Control Measures ◽

Sub Saharan Africa ◽

Limiting Factor ◽

Febrile Reaction ◽

Presumptive Diagnosis ◽

Appropriate Treatment ◽

Sub Saharan ◽

Characteristic Features ◽

And Control

Heartwater is a serious limiting factor for sheep and goat production in the major endemic area of sub-Saharan Africa and therefore most knowledge, research and control methods originate from this region. Whilst the usual or common clinical presentations can be used to make a presumptive diagnosis of heartwater with a good measure of confidence, this is not always the case, and animals suffering from heartwater may be misdiagnosed because their cases do not conform to the expected syndrome, signs and lesions. One aberrant form found occasionally in the Channel Island breeds of cattle and some goats is an afebrile heartwaterlike syndrome. The most constant and characteristic features of this heartwater-like syndrome comprise normal temperature, clinical signs associated with generalised oedema, and nervous signs, especially hypersensitivity. The presumption that the disease under investigation is the afebrile heartwater-like syndrome entails a tentative diagnosis based on history and clinical signs and the response to presumed appropriate treatment (metadiagnosis). The afebrile heartwater-like syndrome presents similarly to peracute heartwater but without the febrile reaction. Peracute cases of heartwater have a high mortality rate, enabling confirmation of the disease on post-mortem examination. Recognition of the afebrile heartwater-like syndrome is important to prevent deaths and identify the need for appropriate control measures.

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Hypertension treatment and control in sub-Saharan Africa

BMJ ◽

10.1136/bmj.317.7150.76 ◽

1998 ◽

Vol 317 (7150) ◽

pp. 76-76 ◽

Cited By ~ 3

Author(s):

J. Burdon ◽

R W Montgomery ◽

R. Walker ◽

N Unwin ◽

K G M M Alberti ◽

...

Keyword(s):

Sub Saharan Africa ◽

Hypertension Treatment ◽

Sub Saharan ◽

And Control

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Susceptibility Profile of Aedes aegypti L. (Diptera: Culicidae) from Montclair, California, to Commonly Used Pesticides, With Note on Resistance to Pyriproxyfen

Journal of Medical Entomology ◽

10.1093/jme/tjz019 ◽

2019 ◽

Vol 56 (4) ◽

pp. 1047-1054 ◽

Cited By ~ 4

Author(s):

Tianyun Su ◽

Jennifer Thieme ◽

Taylor Lura ◽

Min-Lee Cheng ◽

Michelle Q Brown

Keyword(s):

Aedes Aegypti ◽

The United States ◽

Urban Environments ◽

Sub Saharan Africa ◽

Modes Of Action ◽

Breeding Populations ◽

Laboratory Colony ◽

Sub Saharan ◽

The Tropics ◽

And Control

Abstract The peridomestic anthropophilic Aedes aegypti L. (Diptera: Culicidae) is originated from the wild zoophilic subspecies Aedes aegypti formosus in sub-Saharan Africa, and currently has a broad distribution in human-modified environments of the tropics and subtropics worldwide. In California, breeding populations were initially detected in 2013 in the cities of Fresno, Madera, and San Mateo, and now can be found in 188 cities of 12 counties in the state. Recent genetic studies suggest that this species invaded California on multiple occasions from several regions of the United States and northern Mexico prior to initial detection. As an invasive species and vector for numerous arboviruses, Ae. aegypti is a primary target of surveillance and control in California. In southern California city of Montclair, a population was identified in September 2015, from which a short-term colony was established in an insectary. The susceptibility of this field population to commonly used pesticides with various modes of action, including 15 formulations against larvae and four against adults, was determined, in reference to a susceptible laboratory colony of the same species. No resistance was shown to most pesticides tested. However, tolerance or reduced susceptibility to spinosad, spinetoram, diflubezuron, and fipronil was detected, and modest levels of resistance to pyriproxyfen (resistance ratio = 38.7-fold at IE50 and 81.5-fold at IE90) was observed. Results are discussed based on the field usage and modes of action of the pesticides tested. Strategic selection and application of pesticides against this population of Ae. aegypti in the urban environments should be taken into consideration.

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Recurrent Cholera Outbreaks in Sub-Saharan Africa: Moving beyond Epidemiology to Understand the Environmental Reservoirs and Drivers

Challenges ◽

10.3390/challe10010001 ◽

2019 ◽

Vol 10 (1) ◽

pp. 1 ◽

Cited By ~ 7

Author(s):

Willis Gwenzi ◽

Edmond Sanganyado

Keyword(s):

Epidemiological Studies ◽

Sub Saharan Africa ◽

Environmental Drivers ◽

Future Research ◽

Research Directions ◽

Complex Interactions ◽

Future Research Directions ◽

Sub Saharan ◽

And Control ◽

Water Borne

Recurrent cholera outbreaks in sub-Saharan Africa (SSA) attracted a lot of research interest, raising questions about the effectiveness of current prevention and control methods. However, research on cholera and other water-borne diseases in Africa is dominated by epidemiological studies, while investigations on the environmental drivers and reservoirs of cholera remain scarce. The current discourse relating cholera to the environment in SSA is often limited to the rudimentary statement that, “cholera is caused by the consumption of contaminated water and food”. Yet, beyond this simplistic view, literature elsewhere shows that cholera outbreaks are controlled by its complex interactions with environmental drivers and reservoirs. This brings to question whether cholera can be eradicated in SSA without understanding these complex interactions. The current review seeks to (1) highlight the nature and dynamics of recent cholera outbreaks in SSA, (2) discuss the importance of environmental reservoirs of Vibrio cholerae, and anthropogenic and hydroclimatic drivers in controlling the dynamics of cholera outbreaks, and (3) highlight key knowledge gaps and future research directions, and the need to harness emerging research tools such as modeling, machine learning, data mining, and genomics techniques to better understand the cholera dynamics. By bringing to fore these often-overlooked issues in cholera research, we seek to stimulate discussion, and promote a shift toward cross-disciplinary research on cholera and other water-borne diseases in SSA and beyond.

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Research on Invasive Nontyphoidal Salmonella Disease and Developments Towards Better Understanding of Epidemiology, Management, and Control Strategies

Clinical Infectious Diseases ◽

10.1093/cid/ciaa315 ◽

2020 ◽

Vol 71 (Supplement_2) ◽

pp. S127-S129

Author(s):

Samuel Kariuki ◽

Ellis Owusu-Dabo

Keyword(s):

Burden Of Illness ◽

Control Strategies ◽

Sub Saharan Africa ◽

Disease Entity ◽

Middle Income ◽

Diagnostic Strategies ◽

Disease Epidemiology ◽

Middle Income Countries ◽

Sub Saharan ◽

And Control

Abstract During the 11th International Conference on Typhoid and Other Invasive Salmonelloses held in Hanoi, Vietnam, a number of papers were presented on the burden of disease, epidemiology, genomics, management, and control strategies for invasive nontyphoidal Salmonella (iNTS) disease, which is increasingly becoming an important public health threat in low- and middle-income countries, but especially in sub-Saharan Africa (sSA). Although there were minor variations in characteristics of iNTS in different settings (urban vs rural, country to country), it was observed that iNTS has gained greater recognition as a major disease entity in children younger than 5 years. Renewed efforts towards greater understanding of the burden of illness, detection and diagnostic strategies, and management and control of the disease in communities in sSA through the introduction of vaccines will be important.

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After the lockdown: macroeconomic adjustment to the COVID-19 pandemic in sub-Saharan Africa

Oxford Review of Economic Policy ◽

10.1093/oxrep/graa023 ◽

2020 ◽

Vol 36 (Supplement_1) ◽

pp. S338-S358 ◽

Cited By ~ 4

Author(s):

Christopher Adam ◽

Mark Henstridge ◽

Stevan Lee

Keyword(s):

Low Income ◽

Poverty Reduction ◽

Sub Saharan Africa ◽

Policy Options ◽

Macroeconomic Adjustment ◽

The Public ◽

Global Recession ◽

Significant Difference ◽

Short Run ◽

Sub Saharan

Abstract The COVID-19 pandemic is ripping around most of the world, but not in Africa; at least, not yet. At the same time, the policy response is remarkably uniform: most of sub-Saharan Africa went into lockdown from the second week in March. What happens next for the pandemic across Africa is uncertain, but the March lockdowns are unlikely to have contained the epidemic by themselves. What is clear is that the combination of domestic lockdowns and the spill-over from the global recession means immediate and severe hardship. This paper looks beyond the public health aspects of the pandemic to examine the medium-term macroeconomic adjustment challenge confronting domestic policy-makers and international donors. We combine epidemiological and macroeconomic models to calibrate the scale of the combined shock to a representative low-income African economy and to show how alternative policy options for slowing transmission of COVID-19 impact on public revenue, and on GDP in the short run, and hence shape the path to recovery. Noting that the first lockdown, however costly, does not by itself eliminate the likelihood of a re-emergence of the epidemic, we then frame the agenda for key macroeconomic and public finance policies to sustain recovery, growth, and poverty reduction in sub-Saharan Africa. The initial hit to consumption will be up to one-third. All the public policy options are grim. International donor finance of US$40–50 billion, together with domestic reform to accelerate recovery, would make a significant difference to the outlook for poverty.

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Determinants of Restrictive Spirometric Pattern in a Sub-Saharan Urban Setting: A Cross-sectional Population-based Study

The Open Respiratory Medicine Journal ◽

10.2174/1874306401610010086 ◽

2016 ◽

Vol 10 (1) ◽

pp. 86-95 ◽

Cited By ~ 2

Author(s):

Eric Walter Pefura-Yone ◽

Adamou Dodo Balkissou ◽

Andre Pascal Kengne

Keyword(s):

Heart Diseases ◽

Population Based ◽

Forced Expiratory Volume ◽

Urban Setting ◽

Sub Saharan Africa ◽

Cross Sectional ◽

History Of ◽

Sub Saharan ◽

And Control ◽

Restrictive Pattern

Background Restrictive spirometric pattern is a risk factor for all-cause and cause-specific mortality. Objective We assessed the prevalence of restrictive pattern and investigated its determinants in a major sub-Saharan Africa city. Methods Participants were adults (≥ 19 years) who took part in a population-based survey in Yaounde (Cameroon) between December 2013 and April 2014. Restrictive pattern was based on a FVC below the lower limit of the normal (LLN) and a ratio forced expiratory volume in one second (FEV1)/FVC ≥ LLN (LLN-based restrictive pattern) or a FVC <80% and FEV1/FVC ≥ LLN (fixed cut-off based restrictive pattern). Determinants were investigated by logistic regressions. Results In all, 1003 participants [514 (51.2%) women] with a mean age of 33.7 years were included. The prevalence of restrictive pattern was 18.8% (95%CI: 16.6-21.2) based on LLN and 15.0% (13.0-17.2) based on fixed cut-off. LLN-based restrictive pattern was mild in 148 (78.3%) subjects, moderate in 35 (18.5%) and severe in 6 (3.2%). Determinants of LLN-based restrictive pattern were age ≥ 60 years [adjusted odds ratio 2.90 (95%CI 1.46-5.77), p=0.002), history of pulmonary tuberculosis [3.81(1.42-10.20), p=0.008], prevalent heart diseases [3.81 (1.20-12.12), p=0.024] and underweight [5.15(1.30-20.39), p=0.020]. Determinants were largely similar with slightly different effect sizes for fixed cut-off based restrictive pattern. Conclusion Restrictive pattern was very frequent in this city. Clinical implications These results enhance the needs to increase the efforts to prevent and control tuberculosis, cardiovascular diseases and underweight in this setting.

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