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Arboviruses transmitted by mosquito vectors, mainly of the genera Aedes, Anopheles and Culex, are among the main concern for global public health. The rapid spread of these arboviruses causes an increase in government spending, socioeconomic losses and an overload on health systems. Mosquitoes' population control remains the main method to combat the arboviruses spread. This control has been carried out mainly using synthetic pesticides. However, in addition to the possibility of inducing mosquitoes' resistance, synthetic pesticides have harmful effects on both human health and the environment. Thus, the development of eco-friendly products from natural sources, based on agro-industrial by-products, constitutes a viable alternative for the vector mosquitoes' control in immature stages, still in breeding sites. Among the alternatives available, we can highlight the by-products derived from the cashew nut, Anacardium occidentale L. (Anacardiaceae), which has been shown to be a promising alternative due to its ovicidal, larvicidal and insecticidal activities. Considering the efficiency demonstrated both by the by-products of the cashew nut production chain, its constituents, and derived products, the objective of this review is to describe the state-of-the art regarding its use in vector control and to propose future perspectives for the development of products that can be marketed. [ABSTRACT FROM AUTHOR]

Mosquito-borne disease (MBD) control depends largely on a range of public health measures aimed at reducing the spread of infected mosquitoes and human-mosquito contact. These public health measures are generally driven by voluntary, though in few occasions obligatory (e.g., indoor residual spraying), self-protective behaviors by individuals and communities. To develop effective interventions that promote public health measures, the underlying mechanisms that contribute to self-protective behaviors should be well understood. The present scoping review aims to provide a timely overview of how behavior change theories have been applied in the context of MBD control. In addition, the review proposes an integrated model that includes identified key determinants in MBD control behavior, and identifies knowledge gaps to inform future research. A comprehensive search was performed in several databases: MEDLINE, PsycINFO, Embase (Ovid), Web of Science Core Collection, CINAHL, ERIC, and Econ.Lit (EBSCO), as well as registered trials and reviews in CENTRAL and PROSPERO to identify ongoing or unpublished studies. References of included studies and literature reviews were screened, as well as citation tracking in Web of Science, Google Scholar and the malaria database of Behavior Change Impact. This scoping review identified a total of 28 studies. Most studies targeted personal-protective behavioral measures such as adopting, using, or maintaining insecticide-treated bed nets, and were most frequently informed by risk-related behavioral theories. Knowledge and perceived susceptibility of the risk, and related perceived efficacy were identified as key behavioral determinants in the conceptual, integrated human behavior model for MBD control. Numerous studies related to MBD control behavior, especially those focusing on knowledge-attitudes-practices (KAP), often lack a solid theoretical framework, which risks depicting an incomplete understanding of behaviors. In addition, by incorporating various behavioral disciplines into the domain of MBD control, a more comprehensive understanding of key behavioral determinants may be developed and applied in future research and MBD control efforts.

The use of insecticides to control vector mosquitoes is still a necessary practice in many countries. Due to the negative impacts and increasing mosquito resistance to synthetic insecticides, environmentally friendly alternatives are needed. In this context, products derived from the technical cashew nut shell liquid (tCNSL) have shown promise as larvicides to control Aedes aegypti. Our objective was to develop 5 new self-emulsifiable bioactive derivatives from partial tCNSL neutralization reactions with 2 inorganic and 3 organic bases, and to determine their larvicidal activities against Ae. aegypti. We also evaluated their antimicrobial activities and ecotoxicological potential. All five bioactive derivatives of tCNSL had larvicidal activity against Ae. aegypti. Four bioactive derivatives had some bacteriostatic activity, but none had fungicidal activity. Although the five bioactive derivatives are toxic against aquatic organisms, in general they were less toxic against Pseudokirchneriella subcapitata, Daphnia similis, and Oreochromis niloticus, than the larvicides recommended by World Health Organization (WHO). Considering the development of low-cost multifunctional bioproducts it is suggested that the bioactive derivative obtained from tCNSL that was partially neutralized whit NaOH (tCNSLNa) can be incorporated into sanitizing products for Ae. aegypti domestic control. [ABSTRACT FROM AUTHOR]

Plasmodium falciparum has conquistador prowess that depends on its knack for arrested development. This phenomenon is poorly defined/understood; therefore stakeholders neglect its relevance in malaria control strategies. This study provides requisite knowledge and motivation to interested parties to now begin to factor in arrested development of P. falciparum in order to prepare Sub Sahara Africa to strategize for malaria elimination. Reviews of published works and anecdotes were used to generate the reports embodied in this study. P. falciparum arrested development was redefined and contextualized in the light of current laboratory findings that prove that absolute arrest is incompatible with life. During arrest, metabolism is only down-regulated while essential processes continue. Arrested P. falciparum is found in all stages of its complex forms which permits it to cope with inhibitory substances thereby enabling it to exist asymptomatically while modulating some notable genes to resist chemotherapy or mobilizing the resources of the host to shield itself to frustrate host reactions. Arrested development is a defensive strategy par excellence that P. falciparum depends on for relevance in ways that are strikingly complicated. Progress in malaria control would depend on pressuring P. falciparum and its vector to change their habit through strict use of house screening. Man can also apply the principle of arrest to deal with sociopolitical problems especially in Africa. [ABSTRACT FROM AUTHOR]

Abstract Background Bio-efficacy and residual activity of SumiShield® 50WG (50%, w/w) with active ingredient clothianidin, a neonicotinoid compound, was assessed using an insecticide-susceptible laboratory strain of Anopheles arabiensis. Implications of the findings are examined in the context of potential alternative insecticides for indoor residual spraying in Lualaba Province, Democratic Republic of the Congo. Methods Contact surface bioassays were conducted for 48 weeks on four types of walls (unbaked clay, baked clay, cement, painted cement) in simulated semi-field experimental conditions using two different doses of clothianidin active ingredient (200 mg ai/sq m and 300 mg ai/sq m). Additionally, two types of walls (painted cement and baked clay) were examined in occupied houses using the 300-mg dosage. Laboratory-reared An. arabiensis were exposed to treated surfaces or untreated (controls) for 30 min. Mortality was recorded at 24-h intervals for 120 h. Results Under semi-field experimental conditions, there was no significant difference in mortality over time between the two doses of clothianidin. The mortality rates remained above 60% up to 48 weeks on all four wall surface types. The formulation performed better on cement and unbaked clay with a mean final mortality rate above 90%. Under natural conditions, there was no significant difference in response between baked clay and painted cement walls with a mean final mortality rate above 90%. The insecticide also performed significantly better in natural settings compared to semi-field experimental conditions. Conclusion Depending on the type of experimental surface, the residual activity of the two doses of clothianidin was between 28 and 48 weeks based on a 60% mortality endpoint. Clothianidin at 300 mg ai/sq m applied on two house walls (baked clay or painted cement) performed equally well (> 80% mortality) on both surfaces up to week 41 (approximately 9.5 months). Extended bioassay holding periods (up to 120 h) may present with excess natural mortality in the untreated controls, thus complicating analysis.

Mosquito-borne disease (MBD) control depends largely on a range of public health measures aimed at reducing the spread of infected mosquitoes and human-mosquito contact. These public health measures are generally driven by voluntary, though in few occasions obligatory (e.g., indoor residual spraying), self-protective behaviors by individuals and communities. To develop effective interventions that promote public health measures, the underlying mechanisms that contribute to self-protective behaviors should be well understood. The present scoping review aims to provide a timely overview of how behavior change theories have been applied in the context of MBD control. In addition, the review proposes an integrated model that includes identified key determinants in MBD control behavior, and identifies knowledge gaps to inform future research. A comprehensive search was performed in several databases: MEDLINE, PsycINFO, Embase (Ovid), Web of Science Core Collection, CINAHL, ERIC, and Econ.Lit (EBSCO), as well as registered trials and reviews in CENTRAL and PROSPERO to identify ongoing or unpublished studies. References of included studies and literature reviews were screened, as well as citation tracking in Web of Science, Google Scholar and the malaria database of Behavior Change Impact. This scoping review identified a total of 28 studies. Most studies targeted personal-protective behavioral measures such as adopting, using, or maintaining insecticide-treated bed nets, and were most frequently informed by risk-related behavioral theories. Knowledge and perceived susceptibility of the risk, and related perceived efficacy were identified as key behavioral determinants in the conceptual, integrated human behavior model for MBD control. Numerous studies related to MBD control behavior, especially those focusing on knowledge-attitudes-practices (KAP), often lack a solid theoretical framework, which risks depicting an incomplete understanding of behaviors. In addition, by incorporating various behavioral disciplines into the domain of MBD control, a more comprehensive understanding of key behavioral determinants may be developed and applied in future research and MBD control efforts., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:Hans J. Overgaard reports financial support was provided by 10.13039/501100005416Research Council of Norway. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Solidago gigantea and Solidago canadensis (Asteraceae) are two invasive weeds native to North America and introduced in Europe and Asia, where they are spreading quickly threatening the stability of local secondary ecosystems. These two plant invaders may represent an ideal bioresource to be exploited for production of green pesticides. Therefore, herein we evaluated the efficacy of the essential oils (EOs) obtained from their different parts, i.e. leaves, inflorescences and roots, against Culex quinquefasciatus, Spodoptera littoralis and Musca domestica. The essential oil composition was investigated by gas chromatographic-mass spectrometry (GC-MS) analysis. S. canadensis leaf EO was the most toxic to C. quinquefasciatus, with a LC50 of 89.3 μl L−1. The two most effective oils against M. domestica adults were S. canadensis leaf and flower EOs, with LD50 values of 206.9 and 207.1 μg adult−1, respectively. Three EOs highly toxic to S. littoralis were also identified, namely S. gigantea leaf EO, S. canadensis leaf EO and S. gigantea flower EO, with LD50 values of 84.5, 98.9 and 107.4 μg larva−1, respectively. Since the S. canadensis leaf EO was the only green product effective against all the tested insect pests, we selected it for non-target toxicity assays on Eisenia fetida earthworms, along with the leaf EO from S. gigantea. Both the S. canadensis and S. gigantea leaf EOs did not led to mortality of E. fetida adult earthworms, at variance with the positive control α-cypermethrin, allowing us to propose them for pest control purposes in IPM and organic farming. [ABSTRACT FROM AUTHOR]

Nanobiomedicine and parasitology are facing a number of key challenges, which mostly deal with the paucity of effective preventive and curative tools against mosquito-borne diseases and cancer. In this scenario, the employ of botanical and invertebrate extracts as reducing, stabilizing and capping agents for the synthesis of nanoparticles is advantageous over chemical and physical methods, since it is one-pot, cheap, and does not require high pressure, energy, temperature, or the use of highly toxic chemicals. Considering the overlooked connection between mosquito vector activity and the spread of cancer in USA, this review focused on the current knowledge available about green synthesized nanoparticles with efficacy against mosquito-borne diseases and cancer. Green fabricated metal nanoparticles showed antiplasmodial activity that often encompasses the efficacy of currently marked drugs for malaria treatment. They have been also reported as growth inhibitors against dengue virus (serotype DEN-2), with moderate cytotoxicity on mammalian cells. However, this feature is strongly dependent to the botanical agents employed during nanosynthesis. In addition, green nanoparticles have been successfully used to reduce mosquito young instar populations in the field. The final section focuses on some issues for future research, with special reference to the chemical standardization of the botanical extracts used for nanosynthesis and the potential effects on green fabricated nanoparticles on non-target organisms. [ABSTRACT FROM AUTHOR]

In 2005, an outbreak of West Nile virus (WNV) disease occurred in Sacramento County, California; 163 human cases were reported. In response to WNV surveillance indicating increased WNV activity, the Sacramento-Yolo Mosquito and Vector Control District conducted an emergency aerial spray. We determined the economic impact of the outbreak, including the vector control event and the medical cost to treat WNV disease. WNV disease in Sacramento County cost ≈$2.28 million for medical treatment and patients’ productivity loss for both West Nile fever and West Nile neuroinvasive disease. Vector control cost ≈$701,790, including spray procedures and overtime hours. The total economic impact of WNV was $2.98 million. A cost-benefit analysis indicated that only 15 cases of West Nile neuroinvasive disease would need to be prevented to make the emergency spray cost-effective.

A pentane extract of flowers of common milkweed, Asclepias syriaca (Asclepiadaceae), elicited significant orientation from both male and female Culex pipiens in a dual-port flight olfactometer. Analysis of the extract by gas chromatography-mass spectrometry revealed six major constituents in order of relative abundance: benzaldehyde, ( E)-β-ocimene, phenylacetaldehyde, benzyl alcohol, nonanal, and ( E)-2-nonenal. Although not all were collected from the headspace profile of live flowers, a synthetic blend of these six compounds, when presented to mosquitoes in the same levels and proportions that occur in the extract, elicited a response comparable to the extract. Subtractive behavioral bioassays demonstrated that a three-component blend consisting of benzaldehyde, phenylacetaldehyde, and ( E)-2-nonenal was as attractive as the full blend. These findings suggest the potential use of synthetic floral-odor blends for monitoring or control of both male and female disease-vectoring mosquitoes. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To evaluate the larvicidal and pupicidal potential of the methanolic extracts from Moringa oleifera (M. oleifera) plant seeds against malarial vector Anopheles stephensi (A. stephensi) mosquitoes at different concentrations (20, 40, 60, 80 and 100 ppm). Methods: M. oleifera was collected from the area of around Bharathiar University, Coimbatore. The dried plant materials were powdered by an electrical blender. From each sample, 100 g of the plant material were extracted with 300 mL of methanol for 8 h in a Soxhlet apparatus. The extracts were evaporated to dryness in rotary vacuum evaporator to yield 122 mg and 110 mg of dark greenish material (residue) from Arcang amara and Ocimum basilicum, respectively. One gram of the each plant residue was dissolved separately in 100 mL of acetone (stock solution) from which different concentrations, i.e., 20, 40, 60, 80 and 100 ppm were prepared. Results: Larvicidal activity of M. oleifera exhibited in the first to fourth instar larvae of the A. stephensi, and the LC50 and LC90 values were 57.79 ppm and 125.93 ppm for the first instar, 63.90 ppm and 133.07 ppm for the second instar, 72.45 ppm and 139.82 ppm for the third instar, 78.93 ppm and 143.20 ppm for the fourth instar, respectively. During the pupal stage the methanolic extract of M. oleifera showed that the LC50 and LC90 values were 67.77 ppm and 141.00 ppm, respectively. Conclusions: The present study indicates that the phytochemicals derived from M. oleifera seeds extracts are effective mosquito vector control agents and the plant extracts may be used for further integrated pest management programs. [Copyright &y& Elsevier]

Different ecosystems were probed in the vicinity of the city of Bhubaneswar in the Indian state of Orissa for the presence of bacterial spore-formers with activity against mosquito larvae. The most productive sites were places that were flooded during the monsoon season, including roadside ditches and shorelines of ponds. Among 630 isolates screened, 44 (7%) showed larvicidal activity against larvae of Aedes aegypti. The specific activity of the bacterial spore-formers varied greatly. Isolates were found with specific activities superior to the Bacillus thuringiensis israelensis reference strain of the Pasteur Institute. All mosquitocidal strains produced crystal proteins, and based on the biochemical analyses could be classified into the species B. thuringiensis. Such strains possess the potential for the development of new microbial products for mosquito control in India. [ABSTRACT FROM AUTHOR]

Background: Bio-efficacy and residual activity of SumiShield® 50WG (50%, w/w) with active ingredient clothianidin, a neonicotinoid compound, was assessed using an insecticide-susceptible laboratory strain of Anopheles arabiensis. Implications of the findings are examined in the context of potential alternative insecticides for indoor residual spraying in Lualaba Province, Democratic Republic of the Congo. Methods: Contact surface bioassays were conducted for 48 weeks on four types of walls (unbaked clay, baked clay, cement, painted cement) in simulated semi-field experimental conditions using two different doses of clothianidin active ingredient (200 mg ai/sq m and 300 mg ai/sq m). Additionally, two types of walls (painted cement and baked clay) were examined in occupied houses using the 300-mg dosage. Laboratory-reared An. arabiensis were exposed to treated surfaces or untreated (controls) for 30 min. Mortality was recorded at 24-h intervals for 120 h. Results: Under semi-field experimental conditions, there was no significant difference in mortality over time between the two doses of clothianidin. The mortality rates remained above 60% up to 48 weeks on all four wall surface types. The formulation performed better on cement and unbaked clay with a mean final mortality rate above 90%. Under natural conditions, there was no significant difference in response between baked clay and painted cement walls with a mean final mortality rate above 90%. The insecticide also performed significantly better in natural settings compared to semi-field experimental conditions. Conclusion: Depending on the type of experimental surface, the residual activity of the two doses of clothianidin was between 28 and 48 weeks based on a 60% mortality endpoint. Clothianidin at 300 mg ai/sq m applied on two house walls (baked clay or painted cement) performed equally well (> 80% mortality) on both surfaces up to week 41 (approximately 9.5 months). Extended bioassay holding periods (up to 120 h) may present with excess natural mortality in the untreated controls, thus complicating analysis. [ABSTRACT FROM AUTHOR]