Thermal Fogging Research Articles

Prison overcrowding and ill-treatment: sentence reduction as a reparation measure. A view from Latin America and Europe.

In recent years mass protest movements have taken to the streets in many countries across the world. Despite strong international and domestic legal protections for the right to freedom of peaceful assembly and other fundamental human rights, entire assemblies are frequently labelled violent and less lethal weapons are used to disperse them. This article examines the weapons often used by police against public assemblies. Focusing on striking weapons (batons), chemical irri-tants, kinetic impact projectiles and stun grenades, the article uses examples from various countries to illustrate how these weapons are being used and the associated human rights and health impacts. Re-sults: Worrying trends identified include the use of dangerous or untested equipment, such as thermal foggers to deploy chemical irritants; the use of inherently abusive weapons, such as whips or sjam-boks; and the increasing use of certain types of munitions, specifically indiscriminate kinetic impact projectiles. The article seeks to support medical and legal professionals becoming more familiar with the weapons being used in the countries they practice in, the effects of those weapons, and clinical aspects in the presentation and care of those exposed.

Experiments and CFD simulation of downwash airflow and fog distribution discharged from a single-rotor UAV fitted with a pulse-jet thermal fogging machine

A single-rotor UAV fitted with a pulse-jet thermal fogging machine was developed. Computational fluid dynamics (CFD) was employed to simulate the downwash airflow and fog distribution of a single-rotor UAV fitted with a pulse-jet thermal fogger. The developed CFD models were validated in three steps by comparing the calculated results with the measurement experiments. Predicted air velocities of the single-rotor UAV downwash airflow agreed well with measured velocities. The model was also able to predict the fog droplet deposition density of the pulse-jet thermal fogger alone, and fitted to the single-rotor UAV, with the relative errors within 20% and 30%, respectively. The validated CFD model was then employed to investigate the effects of the headwind, crosswind and UAV operating height on the downwash airflow and the fog distribution. Results indicated that when the pulse-jet thermal fogging machine was mounted on the UAV, crosswinds needed to be avoided. At the UAV flight speed of 2 m s−1 and natural wind speed of 1 m s−1, a modest headwind appearance could help improve thermal fogging efficiency at different operating heights. The results have important research value and practical significance for improving the pesticide efficiency of UAV sprayers.

EVALUATION OF THERMAL FOGGER FOR EFFECTIVENESS OF LARVICIDE-ADULTICIDE MIXTURE AGAINST AEDES AEGYPTI

A hand-held thermal fogger was evaluated to spray a mixture of adulticide (Aqualuer 20-20® containing permethrin and piperonyl butoxide) and a biological larvicide (VectoBac®12AS, containing Bacillus thuringiensis subspecies israelensis). Adulticide was applied at maximum label rate of 37 mL/ha while larvicide rates were 0.58, 1.76, 2.64, and 3.50 L/ha (Maximum label rate 2.34 L/ha). Two rows, 7.6 m apart, of bioassay cages containing susceptible 25, 5-7 days old female Aedes aegypti were used to assess effectiveness of the adulticide. Along with each cage were two 473 mL empty plastic cups at 0 and 1.3 m above ground to collect the larvicide. Two control cages and two empty cups were placed upwind in the field for five minutes and removed before the spray. The study was conducted in the evening with five separated replications of a rate. The exposed cages and cups were retrieved from the field and brought back to the laboratory for further observations and tests to determine mortality at 24 and 48 h, respectively. All the adults in all treatment cages and all tests died within 24 h of the spray application. In the lab, larval mortality was assessed by introducing Ae. aegypti larvae, where mortality decreased with increasing distance from the spray line and increased with increasing application rate. The larval mortality at all distances was strongly correlated with application rate (R2 = 0.98). The highest rate used produced 64 -95% larval mortality at all distances. The results indicate that Aqualuer 20-20 and VectoBac 12AS can be applied simultaneously as a mixture achieving complete adult control and considerable larval control.

Comparative efficacy trials with alcohol added d-phenothrin formulations against Aedes aegypti under open-field condition.

Evaporation inhibition of water-based space spray insecticides is necessary to prevent the drifting away of fog droplets and the release of insecticidal actives and to prolong suspension time. To address this problem, hygroscopic alcohols, namely propylene glycol and glycerol, were included as adjuvants in water-based d-phenothrin formulations. The performances of glycerol-added formulation (D1) and propylene glycol-added formulation (D2) in terms of droplet size and efficacy against larvae, pupae and adult Aedes aegypti in an open-field environment were examined and compared to the performance of a formulation without adjuvant (negative control). No significant difference in droplet size was observed between the formulations and fogging methods. The efficacy of cold fogs was significantly higher than thermal fogs for all formulations. D2 was found to be most effective against adult Ae. aegypti, followed by D1 and the negative control. D1 and D2 provided complete knockdown and mortality in adult Ae. aegypti at 10 and 25 m for cold and thermal fogging, respectively. However, all d-phenothrin formulations possessed minimal efficacy on immature Ae. aegypti. The incorporation of non-toxic alcohols as adjuvants in water-based space spray insecticides increased efficacy against adult Ae. aegypti, a major vector for dengue. Propylene glycol was discovered to induce higher adulticidal efficacy than glycerol. © 2023 Society of Chemical Industry.

Modeling Sustained Transmission of Wolbachia among Anopheles Mosquitoes: Implications for Malaria Control in Haiti.

Wolbachia infection in Anopheles albimanus mosquitoes can render mosquitoes less capable of spreading malaria. We developed and analyzed a mechanistic compartmental ordinary differential equation model to evaluate the effectiveness of Wolbachia-based vector control strategies among wild Anopheles mosquitoes in Haiti. The model tracks the mosquito life stages, including egg, larva, and adult (male and female). It also accounts for critical biological effects, such as the maternal transmission of Wolbachia through infected females and cytoplasmic incompatibility, which effectively sterilizes uninfected females when they mate with infected males. We derive and interpret dimensionless numbers, including the basic reproductive number and next-generation numbers. The proposed system presents a backward bifurcation, which indicates a threshold infection that needs to be exceeded to establish a stable Wolbachia infection. The sensitivity analysis ranks the relative importance of the epidemiological parameters at baseline. We simulate different intervention scenarios, including prerelease mitigation using larviciding and thermal fogging before the release, multiple releases of infected populations, and different release times of the year. Our simulations show that the most efficient approach to establishing Wolbachia is to release all the infected mosquitoes immediately after the prerelease mitigation process. Moreover, the model predicts that it is more efficient to release during the dry season than the wet season.

Semi-field evaluation of the space spray efficacy of Fludora Co-Max EW against wild insecticide-resistant Aedes aegypti and Culex quinquefasciatus mosquito populations from Abidjan, Côte d’Ivoire

BackgroundSpace spraying of insecticides is still an important means of controlling Aedes and Culex mosquitoes and arboviral diseases. This study evaluated the space spray efficacy of Fludora Co-Max EW, (water-based insecticide space spray combining flupyradifurone and transfluthrin with film forming aqueous spray technology (FFAST)), against wild insecticide-resistant Aedes aegypti and Culex quinquefasciatus mosquitoes from Abidjan, Côte d’Ivoire, compared with K-Othrine EC (deltamethrin-only product), in small-scale field trials.MethodsWild Ae. aegypti and Cx. quinquefasciatus mosquito larvae were collected in Abidjan, Côte d’Ivoire from August to December 2020. Mosquito larvae were reared in the laboratory until the adult stage. Fludora Co-Max EW and K-Othrine EC were tested against emerged adult females (F0 generation) using ultra-low volume cold fogging (ULV) and thermal fogging (TF) delivery technology, both outdoors and indoors in Agboville, Côte d’Ivoire. Specifically, cages containing 20 mosquitoes each were placed at distances of 10, 25, 50, 75 and 100 m from the spraying line for outdoor spraying, and at ceiling, mid-height and floor levels for indoor house spraying. Knockdown and mortality were recorded at each checkpoint and compared by treatments.ResultsOverall, Fludora Co-Max EW induced significantly higher knockdown and mortality effects in the wild insecticide-resistant Ae. aegypti and Cx. quinquefasciatus compared with K-Othrine EC. In both species, mortality rates with Fludora Co-Max EW were > 80% (up to 100%) with the ULV spray outdoors at each distance checkpoint (i.e. 10–100 m), and 100% with the ULV and TF sprays indoors at all checkpoints (i.e. ceiling, mid-height and floor). K-Othrine EC induced high mortality indoors (97.9–100%), whereas mortality outdoors rapidly declined in Ae. aegypti from 96.7% (10 m) to 36.7% (100 m) with the ULV spray, and from 85.0% (10 m) to 38.3% (100 m) with the TF spray. Fludora Co-Max EW spray applied as ULV spray outdoors had higher knockdown and higher killing effects on Ae. aegypti and Cx. quinquefasciatus than when applied as TF spray. Fludora Co-Max EW performed better against Cx. quinquefasciatus than against Ae. aegypti.ConclusionsFludora Co-Max EW induced high mortality and knockdown effects against wild insecticide-resistant Ae. aegypti and Cx. quinquefasciatus Abidjan strains and performed better than K-Othrine EC. The presence of flupyradifurone and transfluthrin (with new and independent modes of action) and FFAST technology in the current Fludora Co-Max EW formulation appears to have broadened its killing capacity. Fludora Co-Max EW is thus an effective adulticide and may be a useful tool for Aedes and Culex mosquito and arbovirus control in endemic areas.Graphical

Effectiveness of insecticide thermal fogging in hyrax dens in the control of leishmaniasis vectors in rural Palestine: A prospective study.

BackgroundZoonotic cutaneous leishmaniasis (ZCL) is endemic in Palestine and transmitted by Phlebotomus sand flies. They inhabit dens of hyraxes, the reservoir animal. Control measures were implemented since 1996 but cases still occur. We estimated the effect of insecticide thermal fogging inside hyrax dens on sand fly density and leishmania infection.Methodology/Principal findingsDuring July-September 2019, we conducted a 12-week controlled interrupted time series study in two control and one intervention sites containing three hyrax dens each. We implemented Permethrin thermal fogging in the intervention site at week 6. We measured weekly and 36hrs post-intervention sand fly abundance inside dens using CDC light traps. We performed Next-Generation Sequencing to identify sand fly Leishmania spp. infection. We calculated the abundance reduction (AR) using Mulla’s formula and negative binomial regression. Among 11427 collected sand flies, 7339 (64%) were females and 1786 (16%) were Phlebotomus spp. comprising ten species; P. sergenti was the dominant (n = 773, 43%). We report P. arabicus (n = 6) for the first time in Palestine. After fogging, Phlebotomus spp. AR was 93% at 36hrs, 18% and 38% at two and five weeks respectively and 41% during the complete post-intervention period. In the regression models, Phlebotomus spp. density in the intervention site decreased by 74% (IRR: 0.26, 95%CI: 0.11–0.57) at two weeks, 34% (IRR: 0.66, 95%CI: 0.48–0.90) at five weeks and 74% (IRR: 0.26, 95%CI: 0.12–0.59) during the complete period. The density of Leishmania infected sand flies decreased by 65% (IRR: 0.35, 95%CI: 0.26–0.48) at five weeks and 82% (IRR: 0.18, 95%CI: 0.07–0.42) for the complete period (zero infections until week two). Leishmania infection prevalence in the intervention site was 14% pre-intervention and 3.9% post-intervention.Conclusions/SignificanceFogging hyrax dens reduced sand fly abundance and leishmania infection during the 5-week post-intervention period and especially the first two weeks suggesting it could be an effective source-reduction measure for ZCL vectors. Future randomized controlled trials are needed to confirm the effectiveness of fogging hyrax dens on decreasing ZCL incidence.

Thermal fogging with disinfectants and antifreezes enables effective industrial disinfection in subzero cold-chain environment.

During several local COVID-19 outbreaks in China in 2020, SARS-CoV-2 or its RNA was isolated or detected from frozen food or packages, revealing the lack of effective disinfection measures in the frozen food chain and risk of transmission. We explored the possibility that disinfectant plus antifreeze could be delivered as thermal fog to realize effective disinfection at subzero temperatures. We selected two disinfectant-antifreeze combinations, didecyl dimethyl ammonium bromide (DDAB) - propylene glycol (PPG) and peracetic acid (PAA) - triethylene glycol (TEG), and each combination is used with a custom-optimized thermal fogging machine. The two fogs were tested in -20°C freezer warehouses for their disinfection efficacy against a coronavirus porcine epidemic diarrhoea virus (PEDV) field strain, a swine influenza virus (SIV) field strain, and three indicator bacteria, Escherichia coli, Staphylococcus aureus and Bacillus subtilis endospores. At -20°C, the DDAB-PPG or PAA-TEG thermal fogs settle within 3.5 to 4.5h and effectively inactivated PEDV with median tissue culture infective dose of 10-3.5 0.1ml-1 and SIV-H1N1 with hemagglutination titre of 26 ml-1 within 15-60min. DDAB-PPG could inactivate S. aureus and E. coli vegetative cells (106 cfuml-1 ) within 15-60min but not effective on B. subtilis spores, while PAA-TEG could disinfect B. subtilis spores more effectively than for S. aureus and E. coli. We showed that a practical subzero temperature disinfection technology was effective in killing enveloped viruses and vegetative bacteria or bacterial spores. DDAB-PPG or PAA-TEG thermal fogging may be a practical technology for cold-chain disinfection. This subzero temperature disinfection technology could help to meet the urgent public health need of environmental disinfection in frozen food logistics against pandemic and other potential pathogens and to enhance national and international biosecurity.

Evaluation of the efficacy of pyrethroid pesticides against selected strains of Aedes mosquitoes using the who susceptibility test and by thermal fogging

Tests on the efficacy of pyrethroid insecticides in fogging were conducted. These were done in two approaches: 1. A laboratory-based series of the WHO susceptibility tests on F1- generation female adult Aedes mosquitoes, and 2. A series of actual field thermal fogging using caged sentinel F1-generation Aedes mosquitoes. Based on the 98% WHO susceptibility test criterion, strains of Ae. Aegypti have shown to have incipient resistance to pyrethroids, making them less susceptible to laboratory and field tests. Ae. Albopictus was found susceptible to pyrethroids, but it requires further confirmatory tests based on field test results. The study recommends molecular tests on mechanisms involved, nationwide surveillance of susceptibility/resistance of dengue vector mosquitoes, and a review of the chemical control strategies used by authorities.

EFFECTIVENESS OF COMPREHENSIVE CAMPAIGN FOR DENGUE CONTROL IN SOUTHERN PUNJAB, PAKISTAN - AN EXPERIENCE OF 2 YEARS

Objective: To determine the effect of comprehensive campaign for dengue control in Southern Punjab, Pakistan.
 Study Design: Cross sectional study.
 Place and Duration of the Study: Station Health Organization Multan and Departments of Pathology, Combined Military Hospital Multan, from Mar 2019 to Dec 2020.
 Methodology: This study was conducted by implementing a comprehensive campaign by involvement of public health workers in high risk dengue area of Multan. There were five phases of this campaign; awareness, situation analysis, vector surveillance, indoor residual sprays where vector was found and contact tracing of dengue fever cases. The system was developed in 46 Mohallas/localities of Multan. Hot spot for mosquitoes breeding were identified at 15 places. Total of 23 health workers were recruited including 3 female workers. Insecticide spraying was carried out by indoor residual spray pumps & thermal foggers in a cyclic pattern.
 Results: During 2019, 42 larvae were identified followed by insecticide sprays & follow up visits; 26 cases of dengue fever were diagnosed and treated at CMH Multan in a dedicated dengue ward. Contact tracing was carried out and indoor residual sprays were carried out in 20 houses around residence of these cases. In 2020, 5 larvae were identified followed by sprays & follow up visits; 2 cases of dengue fever were diagnosed and treated.
 Conclusion: Comprehensive campaign against dengue fever was quite successful to control spread of dengue fever.

Environment-Friendly Control of Cucumber Downy Mildew Using Chlorine Dioxide

Pseudoperonospora cubensis (downy mildew) is highly virulent to various Cucurbitaceae crops, including cucumber (Cucumis sativus). We tested chlorine dioxide application in a plastic greenhouse for environmentfriendly control of downy mildew disease. Spraying diluted chlorine dioxide suppressed downy mildew disease with 41.2% control efficacy. Thermal fogging with chlorine dioxide had a high control efficacy of 80.9%, confirming that this approach is useful for environment-friendly downy mildew control. Using thermal fogging to control diseases that are greatly affected by humidity, such as downy mildew, may be more effective compared with conventional dilution spray control methods.

Dengue Outbreak Management - Field Experience in Managing Dengue Involving an Urban Residential Area in Kota Kinabalu, Sabah Malaysia


 Introduction: Dengue fever is endemic in Malaysia. It is a major public health challenge that has caused significant morbidity and mortality. A dengue outbreak is contributed by entomological factors, epidemiological and environmental factors. Outbreak response is crucial to reduce cases and death. This study is a descriptive dengue outbreak report in an urban residential area in Kota Kinabalu, Sabah Malaysia.
 Methods: This is a report of a dengue outbreak that started in middle of November 2019 and ended early December 2019. A dengue outbreak in Malaysia is defined when more than one dengue cases is reported in the same locality within 14 days from the date of notification of the first case. Cases were analysed descriptively looking at epidemiology and vector control database.
 Results: This outbreak involved 6 cases. The source reduction activities by elimination of breeding sites were conducted 3 times covering an area of 200 meter radius. A total of 110 premises were checked with coverage of 86%. The number of containers inspected was 923, with 454 outside the premises and 469 inside the premises with no positive results for dengue larvae. Insecticide space spraying via thermal fogging was conducted with added ultra-low volume (ULV) spraying done within the 400 meter radius with coverage of 100%.
 Conclusion: Effective preventive measures have to be paired with responsible communities, as both play very vital roles in the control of dengue.

Factors Affecting the Thermal Fogger for Controlling of “Parlatoria Blanchardi Targ.” on Date-Palm Trees

The aim of this research is to study factors affecting thermal fogger for controlling “Parloria Blanchardi” on the date-palm trees. The outlet tube of the tested fogger was modified by addition tube of 1000 mm length with 30.8 mm diameter. So, the total resonator length increased to 1740 mm to suit with palm-tree heights and easy fog flow. The studied variables included fogger conditions (mobile fogger by human and fogger attached to tricycle), control materials (Malathion, Mineral oil(KZ),“KZ+malathion” and without insecticide), tricycle forward-speeds (0.6, 0.8, 1.0 and 1.2 m/s), the fog angles (30⁰, 45⁰ and 60⁰) and resonator length (74 and 174 cm). The maximum control efficiencies for the nymphs and adult insect were 84.7 and 95.81% respectively, using fog angle of 45⁰, resonator length of 174 cm, control material of “KZ” and forward-speed of 0.6 m/s. The fogger capacities were 93, 108, 120 and 132 tree/h using tricycle forward-speeds of 0.6, 0.8, 1.0 and 1.2 m/s respectively. Using optimum fog angle of 45⁰ with resonator length of 174 cm, the maximum yield of date-palm fruit is 109.6 kg/tree at forward-speed of 0.6 m/s and “KZ” controlling material. Meanwhile, the minimum yield recorded 88.2 kg/tree was obtained under forward-speed of 1.2 m/s and “Malathion” control material. Under fog angle 45⁰ approximately and resonator length of 174, the minimum range of hourly, operation and production costs of using the fogger attached to tricycle at forward speed range of 0.6-1.2 m/s were 24.6-26.2 L.E./h, 0.20-0.26 L.E./tree and 1.96-2.41 L.E./Mg fruit for “KZ”.

Salmonella in dairy calves

Modern calf-raising facilities are not designed for effective cleaning and disinfection. Common issues are lack of a sanitary design, absence of wash bays, improper floor drainage, plus open side curtains and peaks, which negates the use of thermal fogging, which is the only effective method available to decontaminate buildings. Doorway entry and exit points use outdated technology (foot baths) to control infectious agents, and there is a general unawareness by calf raisers and veterinarians of the dangers posed by a relatively small number of Salmonella serotypes such as Salmonella Heidelberg. The dangerous serotypes of Salmonella spp can quickly circumvent current best practices for raising dairy calves and lead to high morbidity and mortality disease outbreaks.

Coleopterans (Hexapoda, Coleoptera) associated with canopies of Callisthene fasciculata (Spr.) Mart. (Vochysiaceae) in the Brazilian Pantanal

Abstract: The study of coleopteran assemblages associated with the canopies of tropical forests can help to expand the knowledge about species diversity and the ecological patterns related to the distribution of this diversity in tropical environments, including wetlands such as the Brazilian Pantanal. In this scenario, the present study examined the effect of temporal variation on the abundance, richness and distribution of the Coleoptera assemblage associated with canopies of Callisthene fasciculata (Spr.) Mart. (Vochysiaceae) throughout the dry and high-water seasonal periods in the Northern Pantanal of Mato Grosso, Brazil. Twelve specimens of C. fasciculata were sampled between 2010 and 2011, six per seasonal period, by thermal fogging with insecticide. A total of 1,663 coleopterans were collected, consisting of 1,572 adults and 91 larvae. The adults are distributed into 38 families and 251 species or morphospecies. Chrysomelidae, Curculionidae, Nitidulidae and Tenebrionidae predominated in terms of abundance and richness. Family distribution, abundance, species richness and trophic guilds varied between the dry and high-water periods, demonstrating a relationship with the phenological conditions of C. fasciculata in addition to seasonality effect. In conclusion, the seasonality imposed by the hydrological regime and its influence on the phenology of C. fasciculata affect the structure of the coleopteran assemblage associated with the canopy of this monodominant vegetation formation in the Pantanal of Mato Grosso.

The Effect of the Atmospheric and Cloud Properties on the Retrieval of Fog Microphysics at Night for MSG/SEVIRI: A Sensitivity Test Using LibRadtran

The simplest way of building a look-up table (LUT) for the retrieval of cloud microphysical properties is to use a standard atmospheric profile and vertically uniform cloud microphysics. Such an assumption has been demonstrated to be incoherent with in-cloud observations. This paper aims to show the effect of some atmospheric conditions associated with fog as well as its macro-and microstructure on brightness temperature (BT) for the MSG/ SEVIRI satellite using libRadtran. The sensitivity tests were performed by gradually changing some features from the initial data, such as cloud cover, total water vapor column, thermal inversion intensity, fog depth, fog microstructure, and others. The results revealed that some variables can cause significant variations on BT and, consequently, discrepancies in the retrieval of fog microphysical properties. Also, a variation as high as 0.5°C was found on BT just by switching uniform to the non-uniform profile of fog microphysics depending on the channel, the droplet size, and optical thickness.

Potential of Outdoor Ultra-Low-Volume Aerosol and Thermal Fog to Suppress the Dengue Vector, Aedes aegypti, Inside Dwellings.

A field study investigated penetration of outdoor ground ultra-low-volume (ULV) aerosol and thermal fog adulticide applications into a dwelling to control the dengue vector Aedes aegypti (L). Four applications of Kontrol 4-4 (4.6% permethrin active ingredient [AI], 4.6% piperonyl butoxide) at the maximum label rate were made at 25-30 m in front of a house at Camp Blanding Joint Training Center, Starke, FL, during summer 2016. The ULV sprayer and thermal fogger nozzles were oriented horizontally, and vehicle travel speeds were 16 and 24 km/h, respectively. All doors and windows of the house were left open. Spray efficacy was assessed using caged female mosquitoes positioned 30 cm above ground, outside and inside of the house. Interior cages were placed in open areas and cryptic sites (i.e., in a closet or cardboard box). A spinner holding 2 rods sized 3 mm × 75 mm was deployed next to each cage (except cryptic sites) to sample droplets and to quantify AI deposition. Thirty minutes after application, cages were removed, slides collected, and mosquitoes transferred to clean cages in the laboratory where mortality was assessed at 24 h posttreatment. The ULV application to the south side of the house produced 100% mortality in outdoor and indoor cages and 24% mortality at cryptic sites. Similarly applied thermal fog resulted in 85% mortality outdoors, 34% indoors, and only 4% in cages at cryptic sites. Application of either method from the west resulted in 19-61% mortality outdoors and 0.5-6.5% indoors. Droplet volume median diameter (Dv0.5) on rods from the ULV application was significantly larger compared with the thermal fogger outdoors, but similar indoors. Outdoors and indoors, the AI deposition from ULV was significantly higher than from thermal fog. Our results show the potential for controlling dengue vectors inside houses with outdoor ground ULV applications in areas where doors and windows are left open for ventilation.

Indoor thermal fogging of the mixture of flupyradifurone and transflutrin on Aedes aegypti mosquitoes susceptible and resistant to pyrethroids in southern Mexico

To evaluate the efficacy of thermal fogging of a mixture of flupyrafirudone (26.3 g/L) and transfluthrin (52.5 g/L) against dengue, Zika y chikungunya Aedes mosquito vectors. Groups of 15 caged Ae. aegypti (susceptible and pyrethroid resistant) mosquitoes were placed in living room, kitchen and bedroom inside houses, after which a dose of 2 and 4 mg/m3 of flupyradifurone and transfluthrine, respectively, was applied as thermal fog. After one hour of exposure mosquitoes were transferred to the laboratory and mortality was recorded after 24 h. The mixture killed 97 to 100% of mosquitoes from the strains and the efficacy was similar independently of their place within the premises. The mixture of flupyrafirudone and transfluthrin applied as thermal fog is a promising tool to control Aedes mosquito populations independently of the pyrethroid-insecticide resistance status.

Use of pyriproxyfen in control of Aedes mosquitoes: Asystematic review.

Dengue is the most rapidly spreading arboviral disease in the world. The current lack of fully protective vaccines and clinical therapeutics creates an urgent need to identify more effective means of controlling Aedes mosquitos, principally Aedes aegypti, as the main vector of dengue. Pyriproxyfen (PPF) is an increasingly used hormone analogue that prevents juvenile Aedes mosquitoes from becoming adults and being incapable of transmitting dengue. The objectives of the review were to (1) Determine the effect of PPF on endpoints including percentage inhibition of emergence to adulthood, larval mortality, and resistance ratios; and (2) Determine the different uses, strengths, and limitations of PPF in control of Aedes. A systematic search was applied to Pubmed, EMBASE, Web of Science, LILACS, Global Health, and the Cochrane database of Systematic Reviews. Out of 1,369 records, 90 studies met the inclusion criteria. Nearly all fit in one of the following four categories 1) Efficacy of granules, 2) Auto-dissemination/horizontal transfer, 3) use of ultra-low volume thermal fogging (ULV), thermal fogging (TF), or fumigant technologies, and 4) assessing mosquito resistance. PPF granules had consistently efficacious results of 90-100% inhibition of emergence for up to 90 days. The evidence is less robust but promising regarding PPF dust for auto-dissemination and the use of PPF in ULV, TF and fumigants. Several studies also found that while mosquito populations were still susceptible to PPF, the lethal concentrations increased among temephos-resistant mosquitoes compared to reference strains. The evidence is strong that PPF does increase immature mortality and adult inhibition in settings represented in the included studies, however future research should focus on areas where there is less evidence (e.g. auto-dissemination, sprays) and new use cases for PPF. A better understanding of the biological mechanisms of cross-resistance between PPF, temephos, and other insecticides will allow control programs to make better informed decisions.

Application with initiative to replace common insect fuel for fogging system with biodiesel

The project addressed the application of biodiesel as a fuel in replacing the petroleum-based liquid carrier in common fogging system. In controlling the population of larvae and adult mosquito using chemical pesticide spraying through fogging method, the dilution rate based on the efficient mixing of pesticide and biodiesel is yet to be investigated. A simulation field trial was conducted indoor in a visible container with the designed dimension of 50 cm × 50 cm × 50 cm with the method of fogging was adapted from the principle of thermal fogger. The biodiesel was produced through the transesterification reaction of palm oil with methanol using hydrotalcite as catalysts. To evaluate the larvicidal and adulticidal mortality, dilution of pesticide which is Sumithion L-40 into biodiesel as liquid carrier is varied. The 5 ml pesticide-carrier mixture with the dilution ratio of 1:9, 3:7 and 5:5 were used and dispersed into the ambient in the form of fog. After several tests, it can be deduced that the most effective dilution ratio for against larvae is 1:9 and adult mosquito is 5:5. The larvae mortality rate achieved 100% at the duration of 117 min due to effective settlement of the spraying droplet of formulation mixture on exposed water. The result also proven that, biodiesel as liquid carrier capable to overcome the solubility problem encountered by the conventional petroleum-based carrier. The adult mosquito needs shorter knockdown time with the higher dosage of pesticide. Sumithion L-40 consists of two active ingredients which are tetramethrin and fenitrothion that provide quick knockdown and residual effect especially to adult mosquito.