Vector Control Method Research Articles

The determination of effective concentration of acethonilic Ipomoea cairica leaves extract against laboratory and field strains of Aedes albopictus and Aedes aegypti mosquito larvae.

Inundated with escalating dengue outbreaks, there is an urgent call to find alternate potential vector control methods as the currently employed method fails to curb the expanding of dengue virus transmission in Malaysia. Supported by this aim, we are interested in exploiting the potential of Ipomoea cairica leaves extract towards primary and secondary vectors of dengue fever, Aedes aegypti and Aedes albopictus. To assess the effectiveness of this plant extracts towards Aedes larvae, we carried out two complementary analyses. First, we observed the comparative effectiveness of larvicidal activity I. cairica extract against the laboratory and field strains of Ae. aegypti and Ae. albopictus. Then, we determined the effective lethal dose of this plant extract against Aedes larvae using log-probit regression analysis of the SPSS 20.0 programme. Results from bioassay demonstrated that I. cairica leaves extract was highly effective to induce larvicidal mortality of Ae. albopictus and Ae. aegypti within 24 and 48 hours post-treatment. Results from the factorial analysis of variance (ANOVA) also indicated that there were significant differences in larvicidal activity between species and strains used (P<0.05). It is interesting to notify that the sequence of effectiveness for the larvicidal activities of I. cairica acethonilic leaves extract is in the manner; Ae. albopictus field strain > Ae. aegypti laboratory strain > Ae. aegypti field strain > Ae. albopictus laboratory strain. The I. cairica leaves extract displayed high larvicidal activity against Ae. albopictus as compared to Ae. aegypti. This is the first evaluation involving the comparison of I. cairica leaves extract effects for the laboratory strain and field strain of Ae. albopictus and Ae. Aegypti.

MATLAB SIMULATION RESEARCH ON PERMANENT MAGNET SYNCHRONOUS MOTOR VECTOR CONTROL

According to the mathematical model of PMSM (permanent magnet synchronous motor) and vector control method, PMSM FOC (vector control) simulation model is built on the basis of MATLAB/Simulink environment. The system adopts the rotor field oriented vector control method of id 0 to realize PMSM decoupling control. The speed regulator and current regulator uses the conventional PI control algorithm, and the inverter adopts SVPWM modulation strategies. The simulation results proved the feasibility of the control method, which provides a good theoretical basis for the parameters of PMSM control system hardware settings. At the same time, building simulation model PMSM FOC SPWM modulation strategy on the basis of FOC SPVWM simulation, making FFT (spectrum analysis) comparison between which and the SVPWM modulation's single phase current. The result that the output harmonic of SVPWM modulation is far less than SPWM modulation proves the advantages of SVPWM modulation strategies. &#x0D;

Advanced Direct Vector Control Method for Optimizing the Operation of a Double-Powered Induction Generator-Based Dual-Rotor Wind Turbine System

The main goal of this paper is to increase the active/reactive power extracted from variable-speed dual-rotor wind power (DRWP) based on doubly-fed induction generators (DFIG) by optimizing its operation using advanced direct vector control. First, the dynamic modeling of different parts of the system is introduced. The DFIG is modeled in the Park reference system. After that, the control techniques are introduced in detail. Direct vector command (DVC) with four-level fuzzy pulse width modulation (FPWM) is used to control the rotor current, thereby controlling the reactive power and active power of the generator. Then, use the neural network design to replace the traditional proportional-integral (PI) controller. Finally, the Matlab/Simulink software is used for simulation to prove the effectiveness of the command strategy using 1.5 MW DRWP. The results show good performance in terms of response time, stability, and precision in following the reference under variable wind speed conditions. In addition, the total harmonic distortion (THD) value of stator current is about 0.13%, being a bit less than other THD values reported in the literature.

Household-level risk factors for Aedes aegypti pupal density in Guayaquil, Ecuador

BackgroundVector-borne diseases are a major cause of disease burden in Guayaquil, Ecuador, especially arboviruses spread by Aedes aegypti mosquitoes. Understanding which household characteristics and risk factors lead to higher Ae. aegypti densities and consequent disease risk can help inform and optimize vector control programs.MethodsCross-sectional entomological surveys were conducted in Guayaquil between 2013 and 2016, covering household demographics, municipal services, potential breeding containers, presence of Ae. aegypti larvae and pupae, and history of using mosquito control methods. A zero-truncated negative binomial regression model was fitted to data for estimating the household pupal index. An additional model assessed the factors of the most productive breeding sites across all of the households.ResultsOf surveyed households, 610 satisfied inclusion criteria. The final household-level model found that collection of large solid items (e.g., furniture and tires) and rainfall the week of and 2 weeks before collection were negatively correlated with average pupae per container, while bed canopy use, unemployment, container water volume, and the interaction between large solid collection and rainfall 2 weeks before the sampling event were positively correlated. Selection of these variables across other top candidate models with ∆AICc < 1 was robust, with the strongest effects from large solid collection and bed canopy use. The final container-level model explaining the characteristics of breeding sites found that contaminated water is positively correlated with Ae. aegypti pupae counts while breeding sites composed of car parts, furniture, sewerage parts, vases, were all negatively correlated.ConclusionsHaving access to municipal services like bulky item pickup was effective at reducing mosquito proliferation in households. Association of bed canopy use with higher mosquito densities is unexpected, and may be a consequence of large local mosquito populations or due to limited use or effectiveness of other vector control methods. The impact of rainfall on mosquito density is multifaceted, as it may both create new habitat and “wash out” existing habitat. Providing services and social/technical interventions focused on monitoring and eliminating productive breeding sites is important for reducing aquatic-stage mosquito densities in households at risk for Ae. aegypti-transmitted diseases.Graphical

A New Fuzzy Direct Power Control of Doubly-Fed Induction Generator in a Wind Power System

This paper presents a new fuzzy direct power control of double-fed induction generators (DFIG) in the wind power system. The most important issue in the application of DFIG generators is proper control of the active and reactive powers of these generators, which are generally carried out by vector control or direct torque/power control methods. Direct power control (DPC) directly controls the active and reactive powers of the stator, and stems from results from direct torque control. To use the vector control method, it is necessary to use conventional PI controllers the main disadvantage being the controller robustness due to the nonlinear behavior of the wind turbine and blade oscillations, and it is unavoidable that after a while, the controller's coefficients need to be updated. Therefore, the main purpose of this paper is to present a direct power control method based on fuzzy construction to overcome the mentioned problem. Simulation results of the proposed strategy are extracted under different performance conditions, and these results are compared with the conventional vector-oriented control method. These comprehensive results exhibit the effectiveness of the proposed fuzzy DPC method for the DFIGs based wind power systems.

Implementation and Comparative Analysis of Time Equivalent Space Vector PWM Method for 3 Phase to 3 Phase Matrix Converter

Nowadays, the matrix converter (MC) has become the prominent power converter. Its unique qualities like single-stage ac to ac conversion, bidirectional power flow, sinusoidal response, unity power factor, and no need for dc-link makes it superior among all power converters. This archival literature investigates the various pulse width modulation (PWM) methods and proposed a novel pulse width modulation (PWM) method named Time Equivalent space vector pulse width modulation. In this article this novel modulation method is compared with exiting carrier-based pulse width control and space vector control methods for a 3 phase to 3 phase matrix converters. Simulation model is built in Matlab and comparative analysis based on total harmonic distortion (THD) will be given for different methods. Simulation results revealed that total harmonic distortion (THD) of Time Equivalent space vector PWM is least so this novel method is best and more efficient in comparison to others.

Co-Evolution of the Presence of Long Lasting Insecticide Treated Nets and Plasmodium falciparum Welch, 1897 Prevalence in Cahata Village (Benguela Province, Angola) during a Village Scale Long-Term of Malaria Vector Control Program

A long term village scale vector control programme was implemented since 2007 in 8 villages around Balombo town (Benguela Province) to compare the efficacy of 4 methods of vector control (1,2). One of them are deltamethrin treated Long Lasting Nets (“LLIN”) “Perma©Net 2.0” with a complete coverage of every sleeping units in 2008 in 2 villages, Caala and Cahata. Cahata was surveyed for 10 years with regular parasitological cross sectional parasitological surveys. During the 3 years following LLIN implementation, a check of their actual usage in every house, or on sleeping units of each patient examined during every parasitological surveys showed that 3 years after the full LLIN distribution less than 50% were still in use, and this percentage regularly decreased to reach 10% and less in 2015 (with 0% during the survey done in October 2005). But Plasmodium falciparum prevalence still decreased with low level until 2014 then it started (slightly) increasing in 2015, and the following years, which correspond to both the National malaria outbreak and the least percentage of LLIN used! But even at that time the plasmodial load was significantly lower in “LLIN users” than in non users showing some maintained personal protection.&#x0D; Even 10 years after the full coverage in LLIN no rebound effect was actually noticed in such natural conditions of life and plasmodial prevalence was even 2 times lower than before the implementation of vector control.&#x0D; Information gained were of great importance for the National Malaria Control program in term of nets replacement with 50% missing in 3 years underlining the need of “stronger” nets and community sensitization for the sustainability of positive results gained with LLIN.

Evaluation of a mosquito home system for controlling Aedes aegypti

BackgroundDengue is a significant public health issue that is caused by Aedes spp. mosquitoes. The current vector control methods are unable to effectively reduce Aedes populations and thus fail to decrease dengue transmission. Hence, there is an urgent need for new tools and strategies to reduce dengue transmission in a wide range of settings. In this study, the Mosquito Home System (MHS) and Mosquito Home Aqua (MHAQ) formulations were assessed as commercial autodissemination traps in laboratory and small-scale field trials.MethodMultiple series of laboratory and small-scale field trials were performed to assess the efficacy of MHS and MHAQ exposed to Ae. aegypti. In the laboratory trials, various parameters such as fecundity, fertility, wing size, oviposition preferences, residual effects, and MHAQ transference to other containers through controlled experiments were tested. For small-scale field trials, the efficacy of the MHS and MHAQ approaches was determined to ascertain whether wild mosquitoes could transfer the MHAQ formulation from MHS stations to ovitraps.ResultsThe data revealed that Ae. aegypti was highly susceptible to low concentrations of MHAQ formulations and had a residual effect of up to 3 months, with MHAQ exposure affecting fecundity, fertility, and mosquito wing size. In the oviposition studies, gravid females strongly preferred the hay infusion compared to tap water and MHAQ during egg-laying in the laboratory. Nevertheless, the use of commercial MHAQ by MHS was highly attractive in field settings compared to conventional ovitraps among local Aedes spp. mosquitoes. In addition, MHAQ horizontal transfer activities in the laboratory and small-scale field trials were demonstrated through larval bioassays. These findings demonstrated the potential of MHAQ to be transferred to new containers in each study site.ConclusionThis study provided proof of principle for the autodissemination of MHAQ. Through further refinement, this technique and device could become an effective oviposition trap and offer an alternative preventive tool for vector control management.Graphical abstract

Case-area targeted interventions (CATI) for reactive dengue control: Modelling effectiveness of vector control and prophylactic drugs in Singapore.

Targeting interventions to areas that have recently experienced cases of disease is one strategy to contain outbreaks of infectious disease. Such case-area targeted interventions (CATI) have become an increasingly popular approach for dengue control but there is little evidence to suggest how precisely targeted or how recent cases need to be, to mount an effective response. The growing interest in the development of prophylactic and therapeutic drugs for dengue has also given new relevance for CATI strategies to interrupt transmission or deliver early treatment. Here we develop a patch-based mathematical model of spatial dengue spread and fit it to spatiotemporal datasets from Singapore. Simulations from this model suggest CATI strategies could be effective, particularly if used in lower density areas. To maximise effectiveness, increasing the size of the radius around an index case should be prioritised even if it results in delays in the intervention being applied. This is partially because large intervention radii ensure individuals receive multiple and regular rounds of drug dosing or vector control, and thus boost overall coverage. Given equivalent efficacy, CATIs using prophylactic drugs are predicted to be more effective than adult mosquito-killing vector control methods and may even offer the possibility of interrupting individual chains of transmission if rapidly deployed. CATI strategies quickly lose their effectiveness if baseline transmission increases or case detection rates fall. These results suggest CATI strategies can play an important role in dengue control but are likely to be most relevant for low transmission areas where high coverage of other non-reactive interventions already exists. Controlled field trials are needed to assess the field efficacy and practical constraints of large operational CATI strategies.

A developed combined control method for induction machine drives based on PWM

PurposeThe purpose of this paper is to develop a combined control (CC) technique based on the direct torque control (DTC) strategy and vector control (VC) method, to improve the overall performance of a three-phase induction machine (TPIM) drives.Design/methodology/approachThe proposed control scheme includes a table-based DTC strategy in connection with a proportional-integral-sliding mode controller and pulse width modulation switching strategy. The control system has merits of DTC technique such as simple structure, less dependent on machine parameters, fast dynamic response and merits of VC technique such as high accuracy and constant switching frequency.FindingsTo validate the effectiveness of the proposed control system, simulation and experimental studies are carried out for a 0.75 kW TPIM in different operating conditions. The achieved results show the superiority of the proposed method in terms of fast dynamics and simple structure compared to the VC strategy and low speed and torque ripples and constant switching frequency compared to the DTC method.Originality/valueCompared to the conventional CC strategies, the control law of the proposed method is based on DTC theory and modulation is established based on VC. In other words, the variable switching frequency which is one of the main disadvantages of the conventional CC strategies is rectified using the proposed CC scheme.

Factors Affecting Uptake and Utilization of Insecticide Treated Net Among Women of Reproductive Age (15 – 49 years) Group Attending Antenatal Clinics in Nasarawa State Nigeria

Background: Vector control is the main path to preventing and reducing malaria transmission. The ownership and use of Insecticide-Treated Nets (ITNs) is the core vector control method and a proven intervention for the control and elimination of malaria in several malaria-endemic countries. This study determined the factors affecting the uptake and utilization of ITN by women in their reproductive age group in Nasarawa State Nigeria. Methods : A descriptive cross sectional study among women of reproductive age group (15 – 49 years) attending Ante Natal Clinic at the Dalhatu Araf Specialist Hospital Lafia, General Hospital Akwanga and Medical Centre Mararaba Gurku in Nasarawa State Nigeria. An interviewer administered questionnaire was used after obtaining an informed consent. Ethical approval was gotten from the state research ethics committee. Data analysis was done using SPSS version 23.0. Results: The mean age of this study population was 27.9 ± 10.6 years. Of the total number of 772 participants in this study, a larger chunk of 707 (91.6%) have heard of insecticide treated net. In addition, most 538 (69.7%) participants said healthcare workers emphasizes the use of insecticide treated net during their antenatal care visits. More than half of the participants, 432 (56.0%) owned an ITN at home. Utilization of insecticide treated nets showed that, 451 (58.4%) sleeps under an insecticide treated net, with 334 (74.1%) of these sleeping under it daily. Reasons for not using ITN for some were; due to heat 137 (30.4%), due to smell 83 (18.3%) and others for no good reason 86 (19.1%) respectively. Beliefs about usefulness of ITN showed 320 (71.0%) felt it is very good and useful in preventing malaria. Conclusions: Most participants are aware of ITN. More than half owned (56%) and sleeps (58.4%) under the ITN. About 71% believed ITN is useful in preventing mosquito bites and malaria. Reasons for declining using ITN among some were due to the ITN’s heat and smell. While more than two-third felt ITN is useful in preventing mosquito bites and malaria. Keywords: Factors, Insecticide Treated Nets, Uptake, Utilization. DOI: 10.7176/JHMN/92-06 Publication date: August 31 st 2021

Analysis and Design of Controller for Doubly-Fed Induction Generator in Wind Energy Application

Now a days, wind energy is developing as a significant wellspring of unpolluted and eco-friendly energy to supplant the enormous scope utilization of expendable wellsprings of energy. Wind Energy is pulling in enthusiasm of analysts everywhere throughout the globe as one of the most significant inexhaustible wellspring of energy. Be that as it may, the primary confinements lie in factor speed wind vitality. The under and above Synchronous speeds are obtained by utilizing a bidirectional power flow converter. In this paper a systematic transfer function model of a Doubly Fed Induction Generator based wind turbine structure connected to grid is developed in Mat lab/Simulink environment. The control structure of generator and that of turbine is developed and implemented. A simple approach is proposed to obtain the gains of Proportional Integral (PI) controller. A systematic detail of this control structure is presented. Under varying load conditions, it is observed that the reactive power is controlled and power factor of the system is maintained close to unity by using this scheme. Stator flux situated vector control method is conveyed for both stator and rotor side converters to supply autonomous control of active and reactive power and keep the DC link voltage consistent.

Large-Scale Deployment and Establishment of Wolbachia Into the Aedes aegypti Population in Rio de Janeiro, Brazil.

Traditional methods of vector control have proven insufficient to reduce the alarming incidence of dengue, Zika, and chikungunya in endemic countries. The bacterium symbiont Wolbachia has emerged as an efficient pathogen-blocking and self-dispersing agent that reduces the vectorial potential of Aedes aegypti populations and potentially impairs arboviral disease transmission. In this work, we report the results of a large-scale Wolbachia intervention in Ilha do Governador, Rio de Janeiro, Brazil. wMel-infected adults were released across residential areas between August 2017 and March 2020. Over 131 weeks, including release and post-release phases, we monitored the wMel prevalence in field specimens and analyzed introgression profiles of two assigned intervention areas, RJ1 and RJ2. Our results revealed that wMel successfully invaded both areas, reaching overall infection rates of 50–70% in RJ1 and 30–60% in RJ2 by the end of the monitoring period. At the neighborhood-level, wMel introgression was heterogeneous in both RJ1 and RJ2, with some profiles sustaining a consistent increase in infection rates and others failing to elicit the same. Correlation analysis revealed a weak overall association between RJ1 and RJ2 (r = 0.2849, p = 0.0236), and an association at a higher degree when comparing different deployment strategies, vehicle or backpack-assisted, within RJ1 (r = 0.4676, p < 0.0001) or RJ2 (r = 0.6263, p < 0.0001). The frequency knockdown resistance (kdr) alleles in wMel-infected specimens from both areas were consistently high over this study. Altogether, these findings corroborate that wMel can be successfully deployed at large-scale as part of vector control intervention strategies and provide the basis for imminent disease impact studies in Southeastern Brazil.

Multivariable State-Feedback Controller Design for PV Inverter Connected to a Weak Grid

This paper presents a robust multi-input multi-output (MIMO) state-feedback control scheme for a photovoltaic (PV) inverter connected to a weak grid. For a weak grid, the point of common coupling (PCC) voltage is very sensitive to the power disturbances and it is dynamically coupled to the PLL dynamics. So far, most of the control methods do not take into accounts these couplings. Therefore, in this paper, the MIMO controller was designed taking into account the dynamics of the phase-locked loop (PLL) and coupling effects between PCC voltage and the active power to enhance the system’s robustness. As result, the robust performance of the PV inverter interfaced to a weak grid was yielded. In addition, the sensitivity of the system to PLL was eliminated, allowing the use of larger PLL bandwidth even in a very weak grid. Based on the eigenvalues analysis method, a comparative study between the proposed control method and the conventional vector control method was performed. The proposed method is verified with simulations in PLECS and real-time simulations in the RT Box. The results show that the proposed MIMO control method preserves the system stability robustness against any change of grid strength, generated power and PLL bandwidth.

CRISPR/Cas-9 mediated knock-in by homology dependent repair in the West Nile Virus vector Culex quinquefasciatus Say

Culex quinquefasciatus Say is a mosquito distributed in both tropical and subtropical regions of the world. It is a night-active, opportunistic blood-feeder and vectors many animal and human diseases, including West Nile Virus and avian malaria. Current vector control methods (e.g. physical/chemical) are increasingly ineffective; use of insecticides also imposes hazards to both human and ecosystem health. Advances in genome editing have allowed the development of genetic insect control methods, which are species-specific and, theoretically, highly effective. CRISPR/Cas9 is a bacteria-derived programmable gene editing tool that is functional in a range of species. We describe the first successful germline gene knock-in by homology dependent repair in C. quinquefasciatus. Using CRISPR/Cas9, we integrated an sgRNA expression cassette and marker gene encoding a fluorescent protein fluorophore (Hr5/IE1-DsRed, Cq7SK-sgRNA) into the kynurenine 3-monooxygenase (kmo) gene. We achieved a minimum transformation rate of 2.8%, similar to rates in other mosquito species. Precise knock-in at the intended locus was confirmed. Insertion homozygotes displayed a white eye phenotype in early-mid larvae and a recessive lethal phenotype by pupation. This work provides an efficient method for engineering C. quinquefasciatus, providing a new tool for developing genetic control tools for this vector.

Vector Control Methods for Star-Connected Three-Phase Induction Motor Drives Under the Open-Phase Failure

Reliability for electric motor drive systems is very vital in some industries. Selecting an appropriate control strategy for driving an electric motor during fault conditions is one of the most important issues mainly for safety-critical applications. Recently, vector control (VC) strategies have been extensively developed for star-connected three-phase induction motor drives during single-phase cut-off fault (COF) based on two different transformation matrices (TMs). Despite the effectiveness of these methods during the fault, these control systems are very complex due to their extensive on-line computation. This paper presents two simple methods based on indirect VC (IVC) and direct VC (DVC) methods for controlling a star-connected three-phase induction motor during the fault condition. The fault in this paper is limited to single-phase COF which can occur in motor stator coils. In this paper, it is shown that using a suitable TM and some changes in the control parameters, it is possible to control the faulted drive system. Performance of the proposed control methods is verified using MATLAB software and DSP/TMS320F28335 controller board for a 0.75kW star-connected three-phase induction motor drive system. The achieved results show the good performance of the introduced control systems in different operating conditions. In addition, the results demonstrate the performance of the proposed VC strategies and that of the previous works are almost the same. However, the proposed VC methods in this paper need less modification in the structure of the standard VC strategy than the previous works.

A novel MTPA and flux weakening method of stator flux oriented control of PMSM

Abstract Permanent magnet synchronous motor (PMSM) has the advantages of high efficiency, high power density and high reliability. It has been widely used in electric vehicles, rail transit, industrial transmission and other fields. Compared with the traditional PMSM control strategy, the Indirect stator-quantities control (ISC) of low torque ripple induction motor has high dynamic response performance in the whole speed range, with high stability and strong security. However, due to the inherent characteristics of PMSM, there are still some difficulties in applying ISC strategy, such as solving the load angle corresponding to the current torque, realizing the maximum torque per ampere (MTPA) control and flux weakening control method in the stator field oriented control algorithm of PMSM. In this paper, theoretical analysis and discussion are carried out for the above difficulties, and an indirect stator vector control (ISC) method for PMSM is proposed. Finally, combined with the electric drive application platform of electric vehicle, the simulation and experimental results verify that the proposed ISC control strategy of PMSM also has good dynamic and steady-state performance in the whole speed range.

Susceptibility of Anopheles gambiae sensu lato to different insecticide classes and mechanisms involved in the South-North transect of Benin

Monitoring vector resistance to insecticides is a major component of resistance management. Adults of Anopheles gambiae s.l. from larvae collected at thirteen sites were tested with papers impregnated with bendiocarb, permethrin; deltamethrin; pirimiphos-methyl and induced bottles of insecticide including bendiocarb; deltamethrin, permethrin and pirimiphos-methyl. Molecular analyses were performed and detoxification enzyme levels were determined for each study site. This study revealed a generalized distribution of resistance of An. gambiae s.l. to pyrethroids (permethrin and deltamethrin) and a clear resistance to carbamates (bendiocarb) especially in the northern region of the country. This vector is still susceptible to organophosphates, especially pirimiphos-methyl, but resistance is a dynamic phenomenon and it would be necessary to monitor the susceptibility of these anopheles to pyrimiphos-methyl and to find alternative vector control methods to slow down the spread of resistance genes.

How public reaction to disease information across scales and the impacts of vector control methods influence disease prevalence and control efficacy.

With the development of social media, the information about vector-borne disease incidence over broad spatial scales can cause demand for local vector control before local risk exists. Anticipatory intervention may still benefit local disease control efforts; however, infection risks are not the only focal concerns governing public demand for vector control. Concern for environmental contamination from pesticides and economic limitations on the frequency and magnitude of control measures also play key roles. Further, public concern may be focused more on ecological factors (i.e., controlling mosquito populations) or on epidemiological factors (i.e., controlling infection-carrying mosquitoes), which may lead to very different control outcomes. Here we introduced a generic Ross-MacDonald model, incorporating these factors under three spatial scales of disease information: local, regional, and global. We tailored and parameterized the model for Zika virus transmitted by Aedes aegypti mosquito. We found that sensitive reactivity caused by larger-scale incidence information could decrease average human infections per patch breeding capacity, however, the associated increase in total control effort plays a larger role, which leads to an overall decrease in control efficacy. The shift of focal concerns from epidemiological to ecological risk could relax the negative effect of the sensitive reactivity on control efficacy when mosquito breeding capacity populations are expected to be large. This work demonstrates that, depending on expected total mosquito breeding capacity population size, and weights of different focal concerns, large-scale disease information can reduce disease infections without lowering control efficacy. Our findings provide guidance for vector-control strategies by considering public reaction through social media.

Estimating the reproduction number and designing the integrated strategies against dengue

Dengue poses social and economic burden in the world. Around 390 million cases have been identified with 96 millions showing clinical symptoms. Vector control methods have been widely used as strategies against dengue. The newly proposed methods, which are currently under investigation, are by the use of vaccine and Wolbachia bacterium. Research to assess their impact on dengue transmission dynamics needs to be conducted before they are publicly implemented. In this paper, the performance of integrated strategies for dengue control using vector controls, vaccine and Wolbachia bacterium has been explored by the use of a mathematical model. The reproduction number, the key quantity to measure the endemic level, has been calculated based on dengue incidence data of Kupang City, Indonesia. An optimal control approach has been applied to investigate the performance of these strategies overtime. We also perform a global sensitivity analysis using the combination of Latin Hypercube Sampling and Partial Rank Correlation Coefficient to determine the influential parameters on the reproduction number and an increase number of dengue cases. The results showed that the dengue reproduction number in Kupang city, Indonesia varies between 1.27 to 2.02, which reflects the reality that dengue is still endemic in Kupang city, Indonesia. The results of sensitivity analysis suggest that the vector control holds an important role in determining the reproduction number. Reduction in the reproduction number would be obtained when the rate of vector control is high. Numerical solutions of the model showed that the combination of vaccine and vector control is sufficient to minimize the dengue incidence. Furthermore, to reach an optimal result, the vector control on adult mosquitoes should be implemented for the entire time period. Our results suggest that although vaccine may be available near future, the implementation of vector control is still required. However, further research needs to be undertaken to assess the impact of the integrated strategies on secondary infections.