Lessons learned, challenges and outlooks for decision-making after a decade of experience monitoring the impact of Indoor Residual Spraying in Benin, West Africa

Abstract Background Since 2008, Indoor Residual Spraying (IRS) has been performed in Benin in 19 districts, including 4 in southern Benin, 9 in Atacora, and 8 in Atacora, Alibori and Donga in northern Benin. However, Benin still struggles with questions about IRS cost benefit and epidemiological impact. We discussed lessons learned and challenges from 10 years of IRS in Benin to be shared with the stakeholders involved in vector control implementation for decisions making. Methods We have assessed entomological parameters in IRS communes since 2008. In all IRS intervention communes, decreases in Human Biting Rate (HBR) of An. gambiae, blood feeding inhibition and Entomological Inoculation Rate (EIR) as compared to control district have been measured. Results EIR was reduced by 80-90%, which is encouraging, but should be observed with caution because: (i) the reduction may be insufficient to decrease epidemiological indicators given that the residual EIR in IRS districts is still higher than it is in some regions of stable malaria; (ii) the reduction in EIR is based on comparisons with control communes, but it is difficult to select control areas with the same environmental characteristics as intervention areas; (iii) despite the reduction, half of all mosquitoes that entered IRS-treated houses succeeded in taking human blood meals. Further, there are behaviors among Benin’s population that limit IRS efficacy, including recent data showing that >90% of people are not protected by IRS between 7-10 PM. This is due to the fact that they remain outside and that most people are not protected from mosquito bites after 10 PM because they either sleep outside without IRS protection or inside without an ITN. Moreover, people have large amounts of clothing hanging on walls where mosquitoes can rest instead of IRS-treated walls. Finally, other components are important to consider in implementing IRS among which: (i) Vector resistance management strategies are sometimes poorly understood; this is actually different from replacing an insecticide by another after the emergence of resistance; (ii) African countries should prepare to finance IRS themselves. Conclusion To curtail residual malaria transmission, additional interventions able to target vectors escaping IRS should be prioritized. Keywords: IRS, Lessons learned, challenges, outlooks, Benin

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Lessons learned, challenges and outlooks for decision-making after a decade of experience monitoring the impact of Indoor Residual Spraying in Benin, West Africa

10.21203/rs.2.17891/v3 ◽

2020 ◽

Author(s):

Martin C Akogbéto ◽

Fortuné Dagnon ◽

Rock Aikpon ◽

Razaki Osse ◽

Albert Salako ◽

...

Keyword(s):

Management Strategies ◽

Resistance Management ◽

Indoor Residual Spraying ◽

Cost Benefit ◽

Blood Feeding ◽

Lessons Learned ◽

African Countries ◽

Residual Malaria Transmission ◽

Epidemiological Impact ◽

The Impact

Abstract Background Since 2008, Indoor Residual Spraying (IRS) has been performed in Benin in 19 districts, including 4 in southern Benin, 9 in Atacora, and 8 in Atacora, Alibori and Donga in northern Benin. However, Benin still struggles with questions about IRS cost benefit and epidemiological impact. We discussed lessons learned and challenges from 10 years of IRS in Benin to be shared with the stakeholders involved in vector control implementation for decisions making. Methods We have assessed entomological parameters in IRS communes since 2008. In all IRS intervention communes, decreases in Human Biting Rate (HBR) of An. gambiae, blood feeding inhibition and Entomological Inoculation Rate (EIR) as compared to control district have been measured. Results EIR was reduced by 80-90%, which is encouraging, but should be observed with caution because: (i) the reduction may be insufficient to decrease epidemiological indicators given that the residual EIR in IRS districts is still higher than it is in some regions of stable malaria; (ii) the reduction in EIR is based on comparisons with control communes, but it is difficult to select control areas with the same environmental characteristics as intervention areas; (iii) despite the reduction, half of all mosquitoes that entered IRS-treated houses succeeded in taking human blood meals. Further, there are behaviors among Benin’s population that limit IRS efficacy, including recent data showing that >90% of people are not protected by IRS between 7-10 PM. This is due to the fact that they remain outside and that most people are not protected from mosquito bites after 10 PM because they either sleep outside without IRS protection or inside without an ITN. Moreover, people have large amounts of clothing hanging on walls where mosquitoes can rest instead of IRS-treated walls. Finally, other components are important to consider in implementing IRS among which: (i) Vector resistance management strategies are sometimes poorly understood; this is actually different from should be replacing one insecticide with another after the emergence of resistance; (ii) African countries should prepare to finance IRS themselves. Conclusion To curtail residual malaria transmission, additional interventions able to target vectors escaping IRS should be prioritized.

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Lessons learned, challenges and outlooks for decision-making after a decade of experience monitoring the impact of Indoor Residual Spraying in Benin, West Africa

10.21203/rs.2.17891/v2 ◽

2020 ◽

Author(s):

Martin C Akogbéto ◽

Fortuné Dagnon ◽

Rock Aikpon ◽

Razaki OSSE ◽

Albert Salako ◽

...

Keyword(s):

Management Strategies ◽

Resistance Management ◽

Indoor Residual Spraying ◽

Cost Benefit ◽

Blood Feeding ◽

Lessons Learned ◽

African Countries ◽

Residual Malaria Transmission ◽

Epidemiological Impact ◽

The Impact

Abstract Background Since 2008, Indoor Residual Spraying (IRS) has been performed in Benin in 19 districts, including 4 in southern Benin, 9 in Atacora, and 8 in Atacora, Alibori and Donga in northern Benin. However, Benin still struggles with questions about IRS cost benefit and epidemiological impact. We discussed lessons learned and challenges from 10 years of IRS in Benin to be shared with the stakeholders involved in vector control implementation for decisions making. Methods We have assessed entomological parameters in IRS communes since 2008. In all IRS intervention communes, decreases in Human Biting Rate (HBR) of An. gambiae , blood feeding inhibition and Entomological Inoculation Rate (EIR) as compared to control district have been measured. Results EIR was reduced by 80-90%, which is encouraging, but should be observed with caution because: (i) the reduction may be insufficient to decrease epidemiological indicators given that the residual EIR in IRS districts is still higher than it is in some regions of stable malaria; (ii) the reduction in EIR is based on comparisons with control communes, but it is difficult to select control areas with the same environmental characteristics as intervention areas; (iii) despite the reduction, half of all mosquitoes that entered IRS-treated houses succeeded in taking human blood meals. Further, there are behaviors among Benin’s population that limit IRS efficacy, including recent data showing that >90% of people are not protected by IRS between 7-10 PM. This is due to the fact that they remain outside and that most people are not protected from mosquito bites after 10 PM because they either sleep outside without IRS protection or inside without an ITN. Moreover, people have large amounts of clothing hanging on walls where mosquitoes can rest instead of IRS-treated walls. Finally, other components are important to consider in implementing IRS among which: (i) Vector resistance management strategies are sometimes poorly understood; this is actually different from replacing an insecticide by another after the emergence of resistance; (ii) African countries should prepare to finance IRS themselves. Conclusion To curtail residual malaria transmission, additional interventions able to target vectors escaping IRS should be prioritized. Keywords: IRS, Lessons learned, challenges, outlooks, Benin

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Lessons learned, challenges and outlooks for decision-making after a decade of experience monitoring the impact of indoor residual spraying in Benin, West Africa

10.21203/rs.2.17891/v4 ◽

2020 ◽

Author(s):

Martin C Akogbéto ◽

Fortuné Dagnon ◽

Rock Aikpon ◽

Razaki OSSE ◽

Albert Salako ◽

...

Keyword(s):

Decision Making ◽

Management Strategies ◽

Resistance Management ◽

Indoor Residual Spraying ◽

Cost Benefit ◽

Blood Feeding ◽

Lessons Learned ◽

African Countries ◽

Residual Malaria Transmission ◽

The Impact

Abstract Background: Since 2008, Indoor Residual Spraying (IRS) has been performed in Benin in 19 districts, including 4 in southern Benin, 9 in Atacora, and 8 in Atacora, Alibori and Donga in northern Benin. However, Benin still struggles with questions about IRS cost benefit and epidemiological impact. Lessons learned and challenges from 10 years of IRS in Benin to be shared with the stakeholders involved in vector control implementation for decision-making.Methods: Entomological parameters have been assessed entomological parameters in IRS communes since 2008. In all IRS intervention communes, decreases in human biting rate (HBR) of Anopheles gambiae, blood feeding inhibition and entomological inoculation rate (EIR) as compared to control district have been measured.Results: EIR was reduced by 80-90%, which is encouraging, but should be observed with caution because: (i) the reduction may be insufficient to decrease epidemiological indicators given that the residual EIR in IRS districts is still higher than it is in some regions of stable malaria; (ii) the reduction in EIR is based on comparisons with control communes, but it is difficult to select control areas with the same environmental characteristics as intervention areas; (iii) despite the reduction, half of all mosquitoes that entered IRS-treated houses succeeded in taking human blood meals. Further, there are behaviours among Benin’s population that limit IRS efficacy, including recent data showing that >90% of people are not protected by IRS between 7-10 PM. This is due to the fact that they remain outdoors and that most people are not protected from mosquito bites after 10 PM because they either sleep outdoors without IRS protection or indoors without an ITN. Moreover, people have large amounts of clothing hanging on walls where mosquitoes can rest instead of IRS-treated walls. Finally, other components are important to consider in implementing IRS among which: (i) Vector resistance management strategies are sometimes poorly understood; this is actually different from the need to replace one insecticide with another after the emergence of resistance; (ii) African countries should prepare to finance IRS themselves.Conclusion: To curtail residual malaria transmission, additional interventions able to target vectors escaping IRS should be prioritized.

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Lessons learned, challenges and outlooks for decision-making after a decade of experience monitoring the impact of indoor residual spraying in Benin, West Africa

Malaria Journal ◽

10.1186/s12936-020-3131-1 ◽

2020 ◽

Vol 19 (1) ◽

Author(s):

Martin C. Akogbéto ◽

Fortuné Dagnon ◽

Rock Aïkpon ◽

Razaki Ossé ◽

Albert S. Salako ◽

...

Keyword(s):

Decision Making ◽

West Africa ◽

Indoor Residual Spraying ◽

Lessons Learned ◽

The Impact

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Cytochrome P450 metabolic resistance (CYP6P9a) to pyrethroids imposes a fitness cost in the major African malaria vector Anopheles funestus

Heredity ◽

10.1038/s41437-020-0304-1 ◽

2020 ◽

Vol 124 (5) ◽

pp. 621-632 ◽

Cited By ~ 3

Author(s):

Magellan Tchouakui ◽

Jacob Riveron Miranda ◽

Leon M. J. Mugenzi ◽

Doumani Djonabaye ◽

Murielle J. Wondji ◽

...

Keyword(s):

Malaria Vector ◽

Management Strategy ◽

Management Strategies ◽

Resistance Management ◽

Anopheles Funestus ◽

Fitness Cost ◽

Malaria Vectors ◽

Hybrid Strain ◽

Metabolic Resistance ◽

The Impact

Abstract Metabolic resistance threatens the sustainability of pyrethroid-based malaria control interventions. Elucidating the fitness cost and potential reversal of metabolic resistance is crucial to design suitable resistance management strategies. Here, we deciphered the fitness cost associated with the CYP6P9a (P450-mediated metabolic resistance) in the major African malaria vector Anopheles funestus. Reciprocal crosses were performed between a pyrethroid susceptible (FANG) and resistant (FUMOZ-R) laboratory strains and the hybrid strains showed intermediate resistance. Genotyping the CYP6P9a-R resistance allele in oviposited females revealed that CYP6P9a negatively impacts the fecundity as homozygote susceptible mosquitoes (CYP6P9a-SS) lay more eggs than heterozygote (OR = 2.04: P = 0.01) and homozygote resistant mosquitoes. CYP6P9a also imposes a significant fitness cost on the larval development as homozygote resistant larvae (CYP6P9a-RR) developed significantly slower than heterozygote and homozygote susceptible mosquitoes (χ2 = 11.2; P = 0.0008). This fitness cost was further supported by the late pupation of homozygote resistant than susceptible mosquitoes (OR = 2.50; P < 0.01). However, CYP6P9a does not impact the longevity as no difference was observed in the life span of mosquitoes with different genotypes (χ2 = 1.6; P = 0.9). In this hybrid strain, a significant decrease of the resistant CYP6P9a-RR genotype was observed after ten generations (χ2 = 6.6; P = 0.01) suggesting a reversal of P450-based resistance in the absence of selection. This study shows that the P450-mediated metabolic resistance imposes a high fitness cost in malaria vectors supporting that a resistance management strategy based on rotation could help mitigate the impact of such resistance.

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Within-host dynamics explain patterns of antibiotic resistance in commensal bacteria

10.1101/217232 ◽

2017 ◽

Cited By ~ 5

Author(s):

Nicholas G. Davies ◽

Stefan Flasche ◽

Mark Jit ◽

Katherine E. Atkins

Keyword(s):

Antibiotic Resistance ◽

Management Strategies ◽

Resistance Management ◽

Population Level ◽

Antibiotic Consumption ◽

Mathematical Framework ◽

Host Immune Responses ◽

Resistance Evolution ◽

Resistant Strains ◽

The Impact

The spread of antibiotic resistance, a major threat to human health, is poorly understood. Empirically, resistant strains gradually increase in prevalence as antibiotic consumption increases, but current mathematical models predict a sharp transition between full sensitivity and full resistance. In other words, we do not understand what drives persistent coexistence between resistant and sensitive strains of disease-causing bacteria in host populations. Without knowing what drives patterns of resistance, we cannot accurately predict the impact of potential strategies for managing resistance. Here, we show that within-host dynamics—bacterial growth, strain competition, and host immune responses—promote frequency-dependent selection for resistant strains, explaining patterns of resistance at the population level. By capturing these processes in a parsimonious mathematical framework, we resolve a long-standing conflict between theory and observation. Our models capture widespread coexistence for multiple bacteria-drug combinations across 30 European countries and explain associations between carriage prevalence and resistance prevalence among bacterial subtypes. A mechanistic understanding of resistance evolution is needed to accurately forecast the impact and effectiveness of resistance-management strategies.

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HRSG Fleet Integrity Management: Lessons Learned From the Field

ASME 2020 Power Conference ◽

10.1115/power2020-16890 ◽

2020 ◽

Author(s):

Andreas Fabricius ◽

James Malloy ◽

Mark Taylor ◽

Peter Jackson ◽

David Moelling

Keyword(s):

Asset Management ◽

Corporate Strategy ◽

Management Strategies ◽

Cost Effective ◽

Operating Mode ◽

Field Work ◽

Lessons Learned ◽

Management Actions ◽

And Performance ◽

The Impact

Abstract This paper presents key lessons learned from hundreds of field missions for assessing the condition of HRSGs at sites around the world. These involved field inspections, root cause of failure analyses and performance assessments on HRSGs of nearly every design, fuel type and operating mode. Statistics on degradation and failure risk areas are presented. Analysis techniques used in both preparing for field work and in assessing field examination results are also discussed. Trends in the evolution of the principal damage mechanisms over the years are examined, and predictions of future problem areas are considered with a view to guiding asset management actions. The impact on HRSG integrity of changes in unit designs, such as the move to flexible operation in response to the increasing contribution from renewables, is also assessed, and likely future trends are outlined. The use of qualitative and quantitative risk-based methods is also discussed and compared to the use of condition-based inspection methods as a basis for a fleet wide management strategy. A case study including a large IPP with several generating assets in its portfolio is presented and the most cost-effective method with respect to current corporate strategy is discussed. Recommendations for fleet management strategies are made.

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Survival and Development of Striacosta albicosta (Smith) (Lepidoptera: Noctuidae) Immature Stages on Dry Beans, non-Bt, Cry1F, and Vip3A Maize

Insects ◽

10.3390/insects10100343 ◽

2019 ◽

Vol 10 (10) ◽

pp. 343 ◽

Cited By ~ 2

Author(s):

Débora G. Montezano ◽

Thomas E. Hunt ◽

Alexandre Specht ◽

Priscila M. C. Luz ◽

Julie A. Peterson

Keyword(s):

Management Strategies ◽

Resistance Management ◽

The United States ◽

Economic Damage ◽

Immature Stages ◽

Dry Beans ◽

Bt Maize ◽

Emergence Period ◽

Striacosta Albicosta ◽

The Impact

Striacosta albicosta is a crop pest that causes economic damage in the United States and Canada. Only maize and dry beans are shown to be suitable hosts, since larval development is incomplete on other hosts. The objective of this study was to describe the developmental parameters of immature stages of S. albicosta feeding on dry beans, non-Bt, Cry1F, and Vip3A maize. For Vip3A, mortality was 100% after 24 h. Larvae feeding on non-Bt maize had the highest larval survival (70.6%) compared to the other hosts. Maize expressing Cry1F had higher survival (31.3%) than dry beans (26.0%). Larvae feeding on dry beans had a significantly faster total development time (74.8 days), compared to 92.5 days for non-Bt and 96.2 days for Cry1F. All larvae developed through seven instars. Pupae from larvae that had fed on non-Bt maize were significantly heavier than pupae from other hosts. An understanding of S. albicosta immature development on various host plants is needed to improve recommendations for effective scouting, treatment timing, and economic thresholds. Differential development can result in an extended adult emergence period, and possibly result in assortative mating between Bt susceptible and resistant populations, which violates the assumption of random mating necessary for current resistance management strategies for Bt maize. Therefore, understanding the impact of host plant and transgenic traits on aspects of pest biology will aid in developing effective integrated pest management and insect resistance management strategies for this pest.

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Vietnam Outsourcing Risks Management

Journal of Applied Business Research (JABR) ◽

10.19030/jabr.v27i1.909 ◽

2011 ◽

Vol 27 (1) ◽

Author(s):

Than Lam

Keyword(s):

Risk Management ◽

Supply Chain ◽

Supply Chain Management ◽

Net Present Value ◽

Leadership Behavior ◽

Management Strategies ◽

Cost Benefit ◽

The United States ◽

Chain Management ◽

The Impact

The exploratory qualitative research study relied on 32 available literatures from 1983 to 2008 to explore the outsourcing risk to the supply chain management infrastructure within the context of an alliance relationship in which the multinational corporation’s manufacturing is outsourced to Vietnam business partners. The paper attempted to define the impact of the Foreign Corrupt Practices Act (FCPA) legislation governing the United States’ Multi National Corporations (MNC), roles of culture, ethicality, and social responsibility principles in assessing and mitigating global risks. The paper discussed ethical leadership behavior in risk management. In addition, the paper presented strategies to integrate a relational exchange model and Cost-of-Risk Analysis (CORA) two-step process for cost-benefit evaluation for mitigating global supply chain management risks. The paper also highlighted financial risk management strategies using a net present value (NPV) of at least zero to embark on expenditure streams. Recommendations, summary and conclusion were also presented.

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Mycotoxins that affect the North American agri-food sector: state of the art and directions for the future

World Mycotoxin Journal ◽

10.3920/wmj2013.1624 ◽

2014 ◽

Vol 7 (1) ◽

pp. 63-82 ◽

Cited By ~ 26

Author(s):

J.D. Miller ◽

A.W. Schaafsma ◽

D. Bhatnagar ◽

G. Bondy ◽

I. Carbone ◽

...

Keyword(s):

North American ◽

Value Chain ◽

Animal Health ◽

Management Strategies ◽

The United States ◽

Lessons Learned ◽

Value Chains ◽

The North ◽

Food And Feed ◽

The Impact

This paper summarises workshop discussions at the 5th international MYCORED meeting in Ottawa, Canada (June 2012) with over 200 participants representing academics, government and industry scientists, government officials and farming organisations (present in roughly equal proportions) from 27 countries. Workshops centred on how mycotoxins in food and feed affect value chains and trade in the region covered by the North American Free Trade Agreement. Crops are contaminated by one or more of five important mycotoxins in parts of Canada and the United States every year, and when contaminated food and feed are consumed in amounts above tolerable limits, human and animal health are at risk. Economic loss from such contamination includes reduced crop yield, grain quality, animal productivity and loss of domestic and export markets. A systematic effort by grain producers, primary, transfer, and terminal elevators, millers and food and feed processers is required to manage these contaminants along the value chain. Workshops discussed lessons learned from investments in plant genetics, fungal genomics, toxicology, analytical and sampling science, management strategies along the food and feed value chains and methods to ameliorate the effects of toxins in grain on animal production and on reducing the impact of mycotoxins on population health in developing countries. These discussions were used to develop a set of priorities and recommendations.

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