Push by a net, pull by a cow: can zooprophylaxis enhance the impact of insecticide treated bed nets on malaria control?

Abstract Background Assessing the effectiveness of malaria control measures in Ghana will require taking transmission dynamics of the disease into account given the influence of climate variability in the region of interest. The impact of preventative interventions on malaria incidence and the prospects of meeting program timelines in Ghana have been investigated using mathematical models based on regionally diverse climatic zones. Methods An ordinary non-linear differential equation model with its associated rate parameters was developed incorporating the transitions between various disease compartments for three ecological zones in Ghana. Model parameters were estimated using data captured on the District Health Information Management System in Ghana from 2008 to 2017.The impact of insecticide treated bed nets and indoor residual spraying on the incidence of malaria were simulated at various levels of coverage and protective effectiveness in each ecological zone. To fit the model, Approximate Bayesian Computational sampling approach was adopted. Results Increasing the coverage levels of both long lasting insecticide treated bed nets or indoor residual spraying activities without a corresponding increase in their proper use or patronage does not impact highly on averting predicted incidence of malaria in Ghana. Improving on the protective efficacy of long lasting insecticide treated bed nets through proper usage could lead to substantial reductions in the predicted incidence of malaria. Similar results were obtained with indoor residual spraying across all zones. Conclusions Projected goals set in the National Strategic plan for malaria control 2014-2020 as well as WHO targets for malaria pre-elimination by 2030 are only likely be achieved if a substantial improvement in treated bed net usage is achieved coupled with targeted deployment of indoor residual spraying with high efficacy.

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Accounting for regional transmission variability and the impact of malaria control interventions in Ghana: a population level mathematical modelling approach

Malaria Journal ◽

10.1186/s12936-020-03496-y ◽

2020 ◽

Vol 19 (1) ◽

Author(s):

Timothy Awine ◽

Sheetal P. Silal

Keyword(s):

Malaria Control ◽

Protective Efficacy ◽

Indoor Residual Spraying ◽

Information Management System ◽

World Health ◽

Bed Nets ◽

Model Parameters ◽

Ecological Zones ◽

Insecticide Treated Bed Nets ◽

The Impact

Abstract Background This paper investigates the impact of malaria preventive interventions in Ghana and the prospects of achieving programme goals using mathematical models based on regionally diverse climatic zones of the country. Methods Using data from the District Health Information Management System of the Ghana Health Service from 2008 to 2017, and historical intervention coverage levels, ordinary non-linear differential equations models were developed. These models incorporated transitions amongst various disease compartments for the three main ecological zones in Ghana. The Approximate Bayesian Computational sampling approach, with a distance based rejection criteria, was adopted for calibration. A leave-one-out approach was used to validate model parameters and the most sensitive parameters were evaluated using a multivariate regression analysis. The impact of insecticide-treated bed nets and their usage, and indoor residual spraying, as well as their protective efficacy on the incidence of malaria, was simulated at various levels of coverage and protective effectiveness in each ecological zone to investigate the prospects of achieving goals of the Ghana malaria control strategy for 2014–2020. Results Increasing the coverage levels of both long-lasting insecticide-treated bed nets and indoor residual spraying activities, without a corresponding increase in their recommended utilization, does not impact highly on averting predicted incidence of malaria. Improving proper usage of long-lasting insecticide-treated bed nets could lead to substantial reductions in the predicted incidence of malaria. Similar results were obtained with indoor residual spraying across all ecological zones of Ghana. Conclusions Projected goals set in the national strategic plan for malaria control 2014–2020, as well as World Health Organization targets for malaria pre-elimination by 2030, are only likely to be achieved if a substantial improvement in treated bed net usage is achieved, coupled with targeted deployment of indoor residual spraying with high community acceptability and efficacy.

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Accounting for regional transmission variability and the impact of malaria control interventions in Ghana: A population level mathematical modelling approach.

10.21203/rs.2.22332/v2 ◽

2020 ◽

Author(s):

Timothy Awine ◽

Sheetal P Silal

Keyword(s):

Malaria Control ◽

Malaria Incidence ◽

Protective Efficacy ◽

Indoor Residual Spraying ◽

Information Management System ◽

Control Measures ◽

Bed Nets ◽

Model Parameters ◽

Insecticide Treated Bed Nets ◽

The Impact

Abstract Background Assessing the effectiveness of malaria control measures in Ghana will require taking transmission dynamics of the disease into account given the influence of climate variability in the region of interest. The impact of preventative interventions on malaria incidence and the prospects of meeting program timelines in Ghana were investigated using mathematical models based on regionally diverse climatic zones. Methods An ordinary non-linear differential equation models with their associated rate parameters were developed incorporating the transitions between various disease compartments for three ecological zones in Ghana. Models were fitted using data from the District Health Information Management System in Ghana from 2008 to 2017 and historical intervention coverage levels. To calibrate the models, Approximate Bayesian Computational sampling approach with a distance based rejection criteria was adopted. A leave-one-out approach was used to validate model parameters and the most sensitive evaluated using a multivariate regression sensitivity analysis. The impact of insecticide treated bed nets and their usage and indoor residual spraying as well as their protective efficacy on the incidence of malaria were simulated at various levels of coverage and protective effectiveness in each ecological zone to investigate the prospects of achieving goals of the malaria control strategy for 2014-2020. Results Increasing the coverage levels of both long lasting insecticide treated bed nets and indoor residual spraying activities without a corresponding increase in their recommended usage does not impact highly on averting predicted incidence of malaria. Improving upon the protective efficacy of long lasting insecticide treated bed nets through proper usage could lead to substantial reductions in the predicted incidence of malaria. Similar results were obtained with indoor residual spraying across all zones.Conclusions Projected goals set in the national strategic plan for malaria control 2014-2020 as well as WHO targets for malaria pre-elimination by 2030 are only likely to be achieved if a substantial improvement in treated bed net usage is achieved coupled with targeted deployment of indoor residual spraying with high community acceptability and efficacy. Key words: model, malaria, interventions, long lasting insecticide bednets, indoor residual spraying

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Accounting for regional transmission variability and the impact of malaria control interventions in Ghana: A population level mathematical modelling approach

10.21203/rs.2.22332/v3 ◽

2020 ◽

Author(s):

Timothy Awine ◽

Sheetal P Silal

Keyword(s):

Malaria Control ◽

Protective Efficacy ◽

Indoor Residual Spraying ◽

Information Management System ◽

Bed Nets ◽

Model Parameters ◽

District Health ◽

Ecological Zones ◽

Insecticide Treated Bed Nets ◽

The Impact

Abstract Background: This paper investigates the impact of malaria preventive interventions in Ghana and the prospects of achieving program goals using mathematical models based on regionally diverse climatic zones of the country. Methods: Using data from the District Health Information Management System of the Ghana Health Service from 2008 to 2017 and historical intervention coverage levels, ordinary non-linear differential equations models were developed incorporating transistions between various disease compartments for the three main ecological zones in Ghana. The Approximate Bayesian Computational sampling approach, with a distance based rejection criteria, was adopted for calibration. A leave-one-out approach was used to validate model parameters and the most sensitive evaluated using a multivariate regression analysis. The impact of insecticide treated bed nets and their usage and indoor residual spraying as well as their protective efficacy on the incidence of malaria were simulated at various levels of coverage and protective effectiveness in each ecological zone to investigate the prospects of achieving goals of the Ghana malaria control strategy for 2014-2020. Results: Increasing the coverage levels of both long lasting insecticide treated bed nets and indoor residual spraying activities without a corresponding increase in their recommended utilisation does not impact highly on averting predicted incidence of malaria. Improving proper usage of long lasting insecticide treated bed nets could lead to substantial reductions in the predicted incidence of malaria. Similar results were obtained with indoor residual spraying across all ecological zones of Ghana. Conclusions: Projected goals set in the national strategic plan for malaria control 2014-2020 as well as WHO targets for malaria pre-elimination by 2030 are only likely to be achieved if a substantial improvement in treated bed net usage is achieved coupled with targeted deployment of indoor residual spraying with high community acceptability and efficacy.

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Accounting for regional transmission variability and the impact of malaria control interventions in Ghana: A population level mathematical modelling approach

10.21203/rs.2.22332/v4 ◽

2020 ◽

Author(s):

Timothy Awine ◽

Sheetal P Silal

Keyword(s):

Malaria Control ◽

Protective Efficacy ◽

Indoor Residual Spraying ◽

Information Management System ◽

World Health ◽

Bed Nets ◽

Model Parameters ◽

Ecological Zones ◽

Insecticide Treated Bed Nets ◽

The Impact

Abstract Background This paper investigates the impact of malaria preventive interventions in Ghana and the prospects of achieving programme goals using mathematical models based on regionally diverse climatic zones of the country. Methods Using data from the District Health Information Management System of the Ghana Health Service from 2008 to 2017, and historical intervention coverage levels, ordinary non-linear differential equations models were developed. These models incorporated transitions amongst various disease compartments for the three main ecological zones in Ghana. The Approximate Bayesian Computational sampling approach, with a distance based rejection criteria, was adopted for calibration. A leave-one-out approach was used to validate model parameters and the most sensitive parameters were evaluated using a multivariate regression analysis. The impact of insecticide-treated bed nets and their usage, and indoor residual spraying, as well as their protective efficacy on the incidence of malaria, was simulated at various levels of coverage and protective effectiveness in each ecological zone to investigate the prospects of achieving goals of the Ghana malaria control strategy for 2014-2020. Results Increasing the coverage levels of both long-lasting insecticide-treated bed nets and indoor residual spraying activities, without a corresponding increase in their recommended utilization, does not impact highly on averting predicted incidence of malaria. Improving proper usage of long-lasting insecticide-treated bed nets could lead to substantial reductions in the predicted incidence of malaria. Similar results were obtained with indoor residual spraying across all ecological zones of Ghana. Conclusions Projected goals set in the national strategic plan for malaria control 2014-2020, as well as World Health Organization targets for malaria pre-elimination by 2030, are only likely to be achieved if a substantial improvement in treated bed net usage is achieved, coupled with targeted deployment of indoor residual spraying with high community acceptability and efficacy.

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6. Malaria

Infectious Disease: A Very Short Introduction ◽

10.1093/actrade/9780199688937.003.0006 ◽

2015 ◽

pp. 66-81

Author(s):

Marta L. Wayne ◽

Benjamin M. Bolker

Keyword(s):

Malaria Control ◽

Ecological Niche ◽

Acute Infection ◽

Bed Nets ◽

Mosquito Vectors ◽

Cumulative Impact ◽

Human Malaria ◽

History Of ◽

Insecticide Treated Bed Nets ◽

The Tropics

Malaria is transmitted to humans through various species of Anopheles mosquitoes. In this century malaria rarely reaches out of the tropics, being limited by the ecological niche of its mosquito vectors. The most widespread strains of malaria are typically chronic and debilitating, rather than causing acute infection and death, but the cumulative impact of malaria on humanity is enormous. ‘Malaria’ considers the complexity of the disease; the history of human malaria; and the strategies employed against the disease, including the use of compatibility-blocking treatments such as quinine, chloroquine, and artemisinin, and encounter-blocking strategies such as residual indoor spraying and insecticide-treated bed nets. It concludes by considering the future for malaria control.

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Analysis of a malaria model with mosquito host choice and bed-net control

International Journal of Biomathematics ◽

10.1142/s1793524515500771 ◽

2015 ◽

Vol 08 (06) ◽

pp. 1550077 ◽

Cited By ~ 2

Author(s):

Bruno Buonomo

Keyword(s):

Reproduction Number ◽

Host Choice ◽

Bed Nets ◽

Bed Net ◽

Host Manipulation ◽

Host Preferences ◽

Insecticide Treated Bed Nets ◽

The Impact ◽

Malaria Model ◽

Disease Free

A malaria model is formulated which includes the enhanced attractiveness of infectious humans to mosquitoes, as result of host manipulation by malaria parasite, and the human behavior, represented by insecticide-treated bed-nets usage. The occurrence of a backward bifurcation at R0 = 1 is shown to be possible, which implies that multiple endemic equilibria co-exist with a stable disease-free equilibrium when the basic reproduction number is less than unity. This phenomenon is found to be caused by disease-induced human mortality. The global asymptotic stability of the endemic equilibrium for R0 > 1 is proved, by using the geometric method for global stability. Therefore, the disease becomes endemic for R0 > 1 regardless of the number of initial cases in both the human and vector populations. Finally, the impact on system dynamics of vector's host preferences and bed-net usage behavior is investigated.

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