Biological and Chemical Control of Mosquito Population by Optimal Control Approach

This paper focuses on the design and analysis of short-term control intervention measures seeking to suppress local populations of Aedes aegypti mosquitoes, the major transmitters of dengue and other vector-borne infections. Besides traditional measures involving the spraying of larvicides and/or insecticides, we include biological control based on the deliberate introduction of predacious species feeding on the aquatic stages of mosquitoes. From the methodological standpoint, our study relies on application of the optimal control modeling framework in combination with the cost-effectiveness analysis. This approach not only enables the design of optimal strategies for external control intervention but also allows for assessment of their performance in terms of the cost-benefit relationship. By examining numerous scenarios derived from combinations of chemical and biological control measures, we try to find out whether the presence of predacious species at the mosquito breeding sites may (partially) replace the common practices of larvicide/insecticide spraying and thus reduce their negative impact on non-target organisms. As a result, we identify two strategies exhibiting the best metrics of cost-effectiveness and provide some useful insights for their possible implementation in practical settings.

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Bifurcation and Stabillity Analysis of HIV Transmission Model with Optimal Control

Journal of Mathematics ◽

10.1155/2021/7471290 ◽

2021 ◽

Vol 2021 ◽

pp. 1-14

Author(s):

Kumama Regassa Cheneke ◽

Koya Purnachandra Rao ◽

Geremew Kenassa Edessa

Keyword(s):

Optimal Control ◽

Cost Effectiveness ◽

Hiv Transmission ◽

Reproduction Number ◽

Transmission Rate ◽

Control Measures ◽

Transmission Model ◽

Progression Rate ◽

Asymptotically Stable ◽

The Cost

A mathematical model of HIV transmission is built and studied in this paper. The system’s equilibrium is calculated. A next-generation matrix is used to calculate the reproduction number. The novel method is used to examine the developed model’s bifurcation and equilibrium stability. The stability analysis result shows that the disease-free equilibrium is locally asymptotically stable if 0 < R 0 < 1 but unstable if R 0 > 1 . However, the endemic equilibrium is locally and globally asymptotically stable if R 0 > 1 and unstable otherwise. The sensitivity analysis shows that the most sensitive parameter that contributes to increasing of the reproduction number is the transmission rate β 2 of HIV transmission from HIV individuals to susceptible individuals and the parameter that contributes to the decreasing of the reproduction number is identified as progression rate η of HIV-infected individuals to AIDS individuals. Furthermore, it is observed that as we change η from 0.1 to 1 , the reproduction number value decreases from 1.205 to 1.189, where the constant value of β 2 = 0.1 . On the other hand, as we change the value of β 2 from 0.1 to 1 , the value of the reproduction number increases from 0.205 to 1.347, where the constant value of η = 0.1 . Further, the developed model is extended to the optimal control model of HIV/AIDS transmission, and the cost-effectiveness of the control strategy is analyzed. Pontraygin’s Maximum Principle (PMP) is applied in the construction of the Hamiltonian function. Moreover, the optimal system is solved using forward and backward Runge–Kutta fourth-order methods. The numerical simulation depicts the number of newly infected HIV individuals and the number of individuals at the AIDS stage reduced as a result of taking control measures. The cost-effectiveness study demonstrates that when combined and used, the preventative and treatment control measures are effective. MATLAB is used to run numerical simulations.

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503. The Misappropriation of COVID-19 Related TV Ad Expenditures

Open Forum Infectious Diseases ◽

10.1093/ofid/ofaa439.696 ◽

2020 ◽

Vol 7 (Supplement_1) ◽

pp. S317-S317

Author(s):

Kartavya J Vyas

Keyword(s):

Cost Effectiveness ◽

Performance Metrics ◽

Control Measures ◽

Mortality Data ◽

Preventive Interventions ◽

Social Distancing ◽

Epidemic Curve ◽

Incidence And Mortality ◽

The Cost ◽

The U.S

Abstract Background With nearly three-fourths of the U.S. population isolated in their homes between early March and the end of May, almost all of whom regularly watch television (TV), it was no surprise that companies began to purchase airtime on major television networks to advertise (ad) their brands and showcase their empathy with the populace. But how would the coronavirus disease 2019 (COVID-19) epidemic curve have changed had these same dollars been allocated to proven preventive interventions? Methods Performance and activity metrics on all COVID-19 related TV ads that have aired in the U.S. between February 26th and June 7th, 2020, were provided by iSpot.tv, Inc., including expenditures. COVID-19 incidence and mortality data were collected from the Centers for Disease Control and Prevention (CDC). Descriptive statistics were performed to calculate total TV ad expenditures and other performance metrics across industry categories. Leveraging a previously published stochastic agent-based model that was used to assess the cost-effectiveness of non-pharmaceutical interventions to control COVID-19, the number of cases that would have been prevented had these same dollars been used for preventive interventions was calculated using cost-effectiveness ratios (CERs), the cost divided by cases prevented. Results A total of 1,513 companies purchased TV airtime during the study period, totaling approximately 1.1 million airings, 215.5 billion impressions, and $2.7 billion in expenditures; most of the expenditures were spent by the restaurant (15.9%), electronics and communications (15.4%), and vehicle (13.7%) industries. The CERs for PPE and social distancing measures were $13,856 and $29,552, respectively; therefore, had all of these TV ad dollars instead been allocated to PPE or social distancing measures, approximately 194,908 and 91,386 cases of COVID-19 may have been prevented by the end of the study period, respectively. Figure 2. COVID-19 cases prevented had TV ad expenditures been reallocated for interventions. Conclusion Americans were inundated with COVID-19 related TV ads during the early months of the pandemic and companies are now showing some signs to relent. In times of disaster, however, it is paramount that the private sector go beyond showcasing their empathy and truly become socially responsible by allocating their funds to proven prevention and control measures. Disclosures All Authors: No reported disclosures

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Fractional-Order Modelling and Optimal Control of Cholera Transmission

Fractal and Fractional ◽

10.3390/fractalfract5040261 ◽

2021 ◽

Vol 5 (4) ◽

pp. 261

Author(s):

Silvério Rosa ◽

Delfim F. M. Torres

Keyword(s):

Mathematical Model ◽

Optimal Control ◽

Sensitivity Analysis ◽

Fractional Order ◽

Control Measures ◽

Time Interval ◽

Variable Order ◽

Effectiveness Analysis ◽

The Cost ◽

Derivative Order

A Caputo-type fractional-order mathematical model for “metapopulation cholera transmission” was recently proposed in [Chaos Solitons Fractals 117 (2018), 37–49]. A sensitivity analysis of that model is done here to show the accuracy relevance of parameter estimation. Then, a fractional optimal control (FOC) problem is formulated and numerically solved. A cost-effectiveness analysis is performed to assess the relevance of studied control measures. Moreover, such analysis allows us to assess the cost and effectiveness of the control measures during intervention. We conclude that the FOC system is more effective only in part of the time interval. For this reason, we propose a system where the derivative order varies along the time interval, being fractional or classical when more advantageous. Such variable-order fractional model, that we call a FractInt system, shows to be the most effective in the control of the disease.

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Cost-effectiveness of influenza control measures: a dynamic transmission model-based analysis

Epidemiology and Infection ◽

10.1017/s0950268813000423 ◽

2013 ◽

Vol 141 (12) ◽

pp. 2581-2594 ◽

Cited By ~ 7

Author(s):

S.-C. CHEN ◽

C.-M. LIAO

Keyword(s):

Cost Effectiveness ◽

Natural Ventilation ◽

Seasonal Influenza ◽

School Setting ◽

Control Measures ◽

Transmission Model ◽

Model Based ◽

Dynamic Transmission Model ◽

Influenza Transmission ◽

The Cost

SUMMARYWe investigated the cost-effectiveness of different influenza control strategies in a school setting in Taiwan. A susceptible-exposure-infected-recovery (SEIR) model was used to simulate influenza transmission and we used a basic reproduction number (R0)–asymptomatic proportion (θ) control scheme to develop a cost-effectiveness model. Based on our dynamic transmission model and economic evaluation, this study indicated that the optimal cost-effective strategy for all modelling scenarios was a combination of natural ventilation and respiratory masking. The estimated costs were US$10/year per person in winter for one kindergarten student. The cost for hand washing was estimated to be US$32/year per person, which was much lower than that of isolation (US$55/year per person) and vaccination (US$86/year per person) in containing seasonal influenza. Transmission model-based, cost-effectiveness analysis can be a useful tool for providing insight into the impacts of economic factors and health benefits on certain strategies for controlling seasonal influenza.

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Cost-Effectiveness Analysis of Optimal Control Measures for Tuberculosis

Bulletin of Mathematical Biology ◽

10.1007/s11538-014-0028-6 ◽

2014 ◽

Vol 76 (10) ◽

pp. 2627-2645 ◽

Cited By ~ 29

Author(s):

Paula Rodrigues ◽

Cristiana J. Silva ◽

Delfim F. M. Torres

Keyword(s):

Optimal Control ◽

Cost Effectiveness ◽

Cost Effectiveness Analysis ◽

Control Measures ◽

Effectiveness Analysis

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Economic burden and prevalence of malaria in companies in Douala, Cameroon

10.21203/rs.3.rs-370739/v1 ◽

2021 ◽

Author(s):

Christian Mbohou Nchetnkou ◽

Herve Nyabeyeuh Nyabeyeuh ◽

Calvin Tonga ◽

Lafortune Kangam ◽

Loick Pradel Kojom Foko ◽

...

Keyword(s):

Negative Impact ◽

Demographic Data ◽

Health Spending ◽

Economic Cost ◽

Control Measures ◽

High Rate ◽

Health Concern ◽

Related Absenteeism ◽

External Management ◽

The Cost

Abstract Background: Malaria is a public health concern in Africa. At the socio-economic level, it represents a brake on the national growth through an increase of health spending, drop of productivity and high rate of absenteeism at the workplace. Some companies have implemented malaria control measures to improve their performance, but the vast majority are slow to follow this approach. Using the cost-of-illness approach, the objective of this study was to estimate the economic impact of malaria in two companies with 24-hour daily activity based in Douala, Cameroon: an agro-food industry nicknamed "AGRO" and a security company nicknamed "SECU".Method: A retrospective analysis of medical and financial records of these companies was carried out to calculate the economic cost of absenteeism, prophylaxis, Internal Management of Malaria cases (IMM) and External Management of Malaria cases (EMM) to these companies. A malaria screening campaign was carried out also in each company in one day from 8 a.m. to 4 p.m. The clinical, anthropometric and socio-demographic data of the employees were collected before the collection of a drop of blood which was subsequently analyzed under the Cyscope fluorescence microscope (Partec-Sysmex, Münster, RFA). Results: Analysis of retrospective data revealed that the prevalence of symptomatic malaria cases had decreased by 8.9% and 25.1% respectively at AGRO and SECU between 2010 and 2012. Regarding the prospective component, 372 employees of the two companies were included in the study. The prevalence of malaria was 26.83% and 26.44% respectively at AGRO in January 2013 and SECU in February 2013. Malaria-related absenteeism accounted for 5% and 17% of general absenteeism at AGRO and SECU respectively. The cost of an EMM accounted for 19.5% and 40.5% of the monthly income of AGRO and SECU workers respectively. Each year, malaria generates a shortfall of US$ 26,426 and US$ 136,824 respectively to AGRO and SECU. Conclusion: Malaria have a negative impact on companies. However, early detection of suspected cases, campaigns to distribute insecticide-treated mosquito nets, Information, Education and Communication within the company could reduce this impact.

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Optimal Control and Cost-Effectiveness Analysis of HIV Model with Educational Campaigns and Therapy

MATEMATIKA ◽

10.11113/matematika.v35.n4.1267 ◽

2019 ◽

Vol 35 (4) ◽

pp. 123-138

Author(s):

. Marsudi ◽

Noor Hidayat ◽

Ratno Bagus Edy Wibowo

Keyword(s):

Optimal Control ◽

Cost Effectiveness ◽

Optimal Control Problem ◽

Control Problem ◽

Necessary Conditions ◽

Cost Effectiveness Analysis ◽

Control Measures ◽

Hiv Model ◽

Effectiveness Analysis ◽

Educational Campaigns

In this paper, we present a deterministic model for the transmission dynamics of HIV, in which educational campaigns and therapy are both important for disease management. We propose and analyze an optimal control problem to investigate the effectiveness and cost-effectiveness of three control measures (educational campaigns, therapy on infected individuals in the asymptomatic stage, and therapy on infected individuals in the pre-AIDS class). We formulate the appropriate optimal control problem and investigate the necessary conditions for disease control in order to determine the role of asymptomatic infection, pre-AIDS, and full-blown AIDS in the spread of HIV. Pontryagin’s Maximum Principle was employed to derive the necessary conditions for the existence of optimal control. The fourth-order Runge-Kutta forward-backwards sweep numerical approximation method was used to solve the optimal control system. The Incremental Cost-Effectiveness Ratio (ICER) was calculated to investigate the cost-effectiveness of all possible combinations of the three control measures. Using cost-effectiveness analysis, we showed that control of therapy on pre-AIDS and a combination of control of educational campaigns and therapy on pre-AIDS provides the most cost-effective strategy to control the disease.

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Biological Control of Stranglervine in Citrus–A Researcher's View

Weed Science ◽

10.1017/s004317450006834x ◽

1986 ◽

Vol 34 (S1) ◽

pp. 31-32 ◽

Cited By ~ 31

Author(s):

W. H. Ridings

Keyword(s):

Biological Control ◽

South America ◽

Ornamental Plant ◽

Control Measures ◽

Citrus Grove ◽

Plant Pest ◽

The Cost ◽

Irrigation Practices ◽

Citrus Trees

Stranglervine (Morrenia odorata Lindl. # MONOD) was identified in 1957 at a commerical citrus grove in Florida. It is believed that this plant pest was introduced into Florida as an ornamental plant from South America. In the early 1960's, it became recognized as a serious weed pest that competed with the citrus trees for sunlight, water, and nutrients; girdled tree limbs; and interfered with spraying, harvesting, and irrigation practices. By the 1970's the vine was distributed throughout most of the citrus-growing areas in Florida. Control measures were limited to herbicides and mechanical cultivation. It was estimated that the cost of controlling this pest was $124/ha/yr. In many instances, control measures were inadequate to keep the vines from becoming established in the trees (11, 12, 13). Studies reported by El-Gholl (4) further demonstrated the inherent ability of this weed to persist.

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Comparative Evaluation of the Cost-Effectiveness of 58 Transportation Control Measures

Transportation Research Record Journal of the Transportation Research Board ◽

10.3141/1641-12 ◽

1998 ◽

Vol 1641 (1) ◽

pp. 97-104 ◽

Cited By ~ 2

Author(s):

Cynthia Pansing ◽

Eric N. Schreffler ◽

Mark A. Sillings

Keyword(s):

Cost Effectiveness ◽

Control Measure ◽

Public Investment ◽

Demand Management ◽

Cost Effective ◽

Alternative Fuel ◽

Control Measures ◽

Standardized Method ◽

Project Data ◽

The Cost

Often when public agencies allocate funding for transportation programs, evaluation of a project’s performance becomes an afterthought, if a consideration at all. Relatively recently, evaluation of project performance has garnered attention as a means for both assessing how cost-effectively public funds help attain transportation and air quality objectives and guiding future public investment decisions. Nonetheless, these efforts suffer at times from a lack of coordination and would benefit from the application of a standardized method. Such a standardized method is applied to evaluate the cost-effectiveness of three categories of transportation control measure (TCM) projects: fixed-route transit, transportation demand management (TDM), and alternative fuel projects. The method provides a means for estimating and quantifying travel mode effects and converting them to net emissions benefits. Three sets of funding programs implemented in California were the subjects of evaluation efforts in which the standardized method was applied. The results of these evaluations are presented, and conclusions are suggested about project cost-effectiveness on the basis of project data and comparisons across categories of projects. On the basis of the evaluation of 58 projects, TDM projects other than telecommunications projects were cost-effective compared with alternative fuel and fixed-route transit projects. In light of the key evaluation findings, an approach and framework for future evaluations of TCM projects to ensure consistency and comparability are proposed. Some future uses of the evaluation data in the form of a centralized database are also suggested.

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