Prevention Of Vector-borne Diseases Research Articles

Insecticide Susceptibility and KDR Mutations in Aedes Albopictus Collected from Seven Districts of Guangyuan city, Northern Sichuan, China.

The Asian tiger mosquito, Aedes albopictus, is an important vector of chikungunya, dengue, yellow fever, and Zika viruses. Vector control remains an important means for the prevention and control of vector-borne diseases. The development of insecticide resistance has become a serious threat to the efficacy of insecticide-based control programs. To understand the resistance status and the underlying genetic mechanism in mosquitoes in Guangyuan City of Sichuan Province, China, we investigated the susceptibility of Ae. albopictus to four commonly used insecticides. We found that all the examined populations were susceptible to malathion and propoxur. However, Ae. albopictus populations in Guangyuan showed a possible resistance to the two tested pyrethroids (beta-cypermethrin and deltamethrin). Notably, phenotypic resistance to deltamethrin was detected in 2 of the 7 populations. The potential of resistance to pyrethroids was confirmed by the presence of knockdown resistance (kdr) related mutations in the voltage-gated sodium channel. Four kdr mutations (V1016G, I1532T, F1534L, and F1534S) were identified to be present alone or in combination, and their distribution displayed significant spatial heterogeneity. These findings are helpful for making evidence-based mosquito control strategies and highlight the need to regularly monitor the dynamics of pyrethroid resistance in this city.

Assess the Level of Knowledge Regarding Prevention and Control of Vector Borne Diseases among Farmers

Assess the Level of Knowledge Regarding Prevention and Control of Vector Borne Diseases among Farmers

MBORS: Mosquito vector Biocontrol Ontology and Recommendation System

Background & objectives: Mosquito vectors are disease-causing insects, responsible for various life-threatening vector-borne diseases such as dengue, Zika, malaria, chikungunya, and lymphatic filariasis. In practice, synthetic insecticides are used to control the mosquito vector, but, the continuous usage of synthetic insecticides is toxic to human health resulting in communicable diseases. Non-toxic biocontrol agents such as bacteria, fungus, plants, and mosquito densoviruses play a vital role in controlling mosquitoes. Community awareness of mosquito biocontrol agents is required to control vector-borne diseases. Mosquito vector-based ontology facilitates mosquito biocontrol by providing information such as species names, pathogen-associated diseases, and biological controlling agents. It helps to explore the associations among the mosquitoes and their biocontrol agents in the form of rules. The Mosquito vector-based Biocontrol Ontology Recommendation System (MBORS) provides the knowledge on mosquito-associated biocontrol agents to control the vector at the early stage of the mosquitoes such as eggs, larvae, pupae, and adults. This paper proposes MBORS for the prevention and effective control of vector-borne diseases. The Mosquito Vector Association ontology (MVAont) suggests the appropriate mosquito vector biocontrol agents (MosqVecRS) for related diseases. Methods: Natural Language Processing and Data mining are employed to develop the MBORS. While Tokenization, Part-of-speech Tagging (POS), Named Entity Recognition (NER), and rule-based text mining techniques are used to identify the mosquito ontology concepts, the data mining apriori algorithm is used to predict the associations among them. Results: The outcome of the MBORS results in MVAont as Web Ontology Language (OWL) representation and MosqVecRS as an Android application. The developed ontology and recommendation system are freely available on the web portal. Interpretation & conclusion: The MVAont predicts harmless biocontrol agents which help to diminish the rate of vector-borne diseases. On the other hand, the MosqVecRS system raises awareness of vectors and vector-borne diseases by recommending suitable biocontrol agents to the vector control community and researchers.

Influence of dengue virus serotypes on the abundance of Aedes aegypti insect-specific viruses (ISVs).

A comprehensive understanding of the virome in mosquito vectors is crucial for assessing the potential transmission of viral agents, designing effective vector control strategies, and advancing our knowledge of insect-specific viruses (ISVs). In this study, we utilized Oxford Nanopore Technologies metagenomics to characterize the virome of Aedes aegypti mosquitoes collected in various regions of Colombia, a country hyperendemic for dengue virus (DENV). Analyses were conducted on groups of insects with previous natural DENV infection (DENV-1 and DENV-2 serotypes), as well as mosquito samples that tested negative for virus infection (DENV-negative). Our findings indicate that the Ae. aegypti virome exhibits a similar viral composition at the ISV family and species levels in both DENV-positive and DENV-negative samples across all study sites. However, differences were observed in the relative abundance of viral families such as Phenuiviridae, Partitiviridae, Flaviviridae, Rhabdoviridae, Picornaviridae, Bromoviridae, and Virgaviridae, depending on the serotype of DENV-1 and DENV-2. In addition, ISVs are frequently found in the core virome of Ae. aegypti, such as Phasi Charoen-like phasivirus (PCLV), which was the most prevalent and showed variable abundance in relation to the presence of specific DENV serotypes. Phylogenetic analyses of the L, M, and S segments of the PCLV genome are associated with sequences from different regions of the world but show close clustering with sequences from Brazil and Guadeloupe, indicating a shared evolutionary relationship. The profiling of the Ae. aegypti virome in Colombia presented here improves our understanding of viral diversity within mosquito vectors and provides information that opens the way to possible connections between ISVs and arboviruses. Future studies aimed at deepening our understanding of the mechanisms underlying the interactions between ISVs and DENV serotypes in Ae. aegypti could provide valuable information for the design of effective vector-borne viral disease control and prevention strategies.IMPORTANCEIn this study, we employed a metagenomic approach to characterize the virome of Aedes aegypti mosquitoes, with and without natural DENV infection, in several regions of Colombia. Our findings indicate that the mosquito virome is predominantly composed of insect-specific viruses (ISVs) and that infection with different DENV serotypes (DENV-1 and DENV-2) could lead to alterations in the relative abundance of viral families and species constituting the core virome in Aedes spp. The study also sheds light on the identification of the genome and evolutionary relationships of the Phasi Charoen-like phasivirus in Ae. aegypti in Colombia, a widespread ISV in areas with high DENV incidence.

Novel strains of Culex flavivirus and Hubei chryso-like virus 1 from the Anopheles mosquito in western Kenya

Surveillance of mosquito vectors is critical for early detection, prevention and control of vector borne diseases. In this study we used advanced molecular tools, such as DNA barcoding in combination with novel sequencing technologies to discover new and already known viruses in genetically identified mosquito species. Mosquitoes were captured using BG sentinel traps in Western Kenya during May and July 2019, and homogenized individually before pooled into groups of ten mosquitoes. The pools and individual samples were then used for molecular analysis and to infect cell cultures. Of a total of fifty-four (54) 10-pools, thirteen (13) showed cytopathic effect (CPE) on VeroB4 cells, eighteen (18) showed CPE on C6/36 cells. Eight (8) 10-pools out of the 31 CPE positive pools showed CPE on both VeroB4 and C6/36 cells. When using reverse transcriptase polymerase chain reaction (RT-PCR), Sanger sequencing and Twist Comprehensive Viral Research Panel (CVRP) (Twist Biosciences), all pools were found negative by RT-PCR when using genus specific primers targeting alphaviruses, orthobunyaviruses and virus specific primers towards o'nyong-nyong virus, chikungunya virus and Sindbis virus (previously reported to circulate in the region). Interestingly, five pools were RT-PCR positive for flavivirus. Two of the RT-PCR positive pools showed CPE on both VeroB4 and C6/36 cells, two pools showed CPE on C6/36 cells alone and one pool on VeroB4 cells only. Fifty individual mosquito homogenates from the five RT-PCR positive 10-pools were analyzed further for flavivirus RNA. Of these, 19 out of the 50 individual mosquito homogenates indicated the presence of flavivirus RNA. Barcoding of the flavivirus positive mosquitoes revealed the mosquito species as Aedes aegypti (1), Mansonia uniformis (6), Anopheles spp (3), Culex pipiens (5), Culex spp (1), Coquilletidia metallica (2) and Culex quinquefasciatus (1). Of the 19 flavivirus positive individual mosquitoes, five (5) virus positive homogenates were sequenced. Genome sequences of two viruses were completed. One was identified as the single-stranded RNA Culex flavivirus and the other as the double-stranded RNA Hubei chryso-like virus 1. Both viruses were found in the same Anopheles spp. homogenate extracted from a sample that showed CPE on both VeroB4 and C6/36 cells. The detection of both viruses in a single mosquito homogenate indicated coinfection. Phylogenetic analyses suggested that the Culex flavivirus sequence detected was closely related to a Culex flavivirus isolated from Uganda in 2008. All four Hubei chryso-like virus 1 segments clusters closely to Hubei chryso-like virus 1 strains isolated in Australia, China and USA. Two novel strains of insect-specific viruses in Anopheles mosquitoes were detected and characterized.

Improving vector-borne disease control in Albufeira

Abstract The Albufeira Health Centre (CSA) comprises various functional units within primary healthcare. Recognizing the limited awareness of colleagues regarding the Vector Surveillance Network (REVIVE), responsible for entomological surveillance of mosquitoes, ticks, and sandflies, the Public Health Unit (USP) initiated a project to improve coordination and knowledge sharing. Implemented in April 2023, the project involved a multidisciplinary team. Informational materials on vector surveillance and control, clinical guidance for common vector-borne diseases (VBDs), tick collection protocols, and specimen registration forms were distributed. A video highlighting entomological surveillance and strategies for prevention and control was disseminated. To date, the project has recorded 45 views of the video (51%). A questionnaire distributed among the target population revealed that only 20% had knowledge of the epidemiological importance of vectors in the Algarve region. None were familiar with REVIVE or its work. Furthermore, participants were not acquainted with the Aedes albopictus mosquito species. Regarding ticks, 20% felt confident in tick removal, but none were aware of the tick genera in the Algarve region. Only 20% were aware of notifiable vector-borne diseases through SINAVE. Training sessions on this topic were suggested. The project emphasized the significance of communication and collaboration among healthcare professionals in the prevention and control of vector-borne diseases. It highlighted the need for continuous education on VBDs, surveillance techniques, and control measures. This innovative project can serve as a model for healthcare centres and countries, contributing to global efforts to improve the response to vector-borne diseases. The project's outreach extended to the Municipal Albufeira Animal Welfare Centre. A new questionnaire will be distributed to gather additional insights and enhance the impact of the project. Key messages • The project aims to improve integration of primary healthcare services for vector-borne diseases, increasing awareness and training for healthcare professionals. • This innovative project promotes prevention culture and replicable adaptations for improved response to vector-borne diseases.

Modern Means of Personal Protection of People from Bloodsucking Arthropods

The review focuses on the means of personal protection of people from blood-sucking arthropods, mainly from Ixodidae ticks. Individual (personal) protection of humans is an important component of nonspecific prevention of natural-focal vector-borne diseases. The paper considers statistical data describing the level of significance and relevance of the information about the infections transmitted by ticks, for instance, tick-borne viral encephalitis, tick-borne borreliosis etc. Presented are the characteristics of different groups of personal protection means: insectoacaricidal, repellent, and insectoacaricidal-repellent ones. Indicators of their effectiveness are assessed; their practical use, as well as the features of special protective clothing and the necessity of its application is described. The toxicity of protective clothing is reduced through a lining fabric, local inserts of fabric with insectoacaricidal impregnation and the use of underwear. Different interpretation of the term “repellent” in the domestic and foreign literature, and also two different approaches (“Eastern” and “Western”) to the design and manufacture of personal protection means for people against attacks of blood-sucking arthropods, including Ixodidae ticks, in Russia and Western Europe countries and the USA is discussed. The paper highlights the effect of different pyrethroid groups on the behavioral reactions of ticks. It is shown that in the Russian Federation the use of permethrin is prohibited for the treatment of protective clothing against blood-sucking arthropods, in particular against the taiga tick Ixodes persulcatus, which is the main vector of dangerous infections across the major part of the country (in the east of the European part, the Urals, Siberia and the Far East).

Pillars for successful operationalization of one health as an ecosystem approach: experience from a human-animal interface in the Maasai steppe in Tanzania

BackgroundSolving complex public health challenges requires integrated approaches to health, such as One Health. A key element of the One Health approach is the interrelationship between human, animal and environmental health and the associated multistakeholder collaboration across many cultural, disciplinary, institutional and sectoral boundaries. Here we describe a pragmatic approach for One Health operationalisation basing on our long-term engagement with communities faced with health challenges in a human-livestock-wildlife interface in the Maasai steppe in northern Tanzania.MethodsUsing a qualitative study design we performed an outcome mapping to document insights on results integration from our previous project. Data were collected through participatory community meetings, in-depth interviews and field observations. Field notes were coded and analysed using inductive thematic analysis.ResultsWe found that effective implementation of One Health interventions in complex ecosystems works best by understanding local conditions and their context and by working closely with the local people and relevant disciplinary players as one complex adaptive system. Community engagement, systems analysis, transdisciplinarity as well as political commitment played critical roles in successful operationalization of One Health. We have further emphasized that project ownership is as important to the local community as it is to the researchers. When used in combination, these elements (community engagement, systems analysis, transdisciplinarity) provide essential pillars for co-creation and maintaining collective action to set a common vision across disciplines, serving as inputs for a metrics-based toolbox for One Health operationalisation.ConclusionConsidering the novelty and complexity of One Health operationalisation, there is need also to develop scorecard-based guidance for assessment of One Health programs at local and national level. This paper proposes a framework for the optimization of an ecosystems-based One Health approach for prevention and control of Vector-Borne Diseases implemented at the local, sub-national or national level.

Worldwide Status of Insecticide Resistance of Aedes aegypti and Ae. albopictus, Vectors of Arboviruses of Chikungunya, Dengue, Zika and Yellow Fever.

Controlling of Aedes aegypti and Ae. albopictus, vectors of five important mosquito-borne diseases, is known as the most effective method to prevent the transmission of arboviruses to humans, but the emergence of insecticide resistance is threat for control and prevention of vector borne diseases. A better understanding of mosquito resistance to insecticides will help to develop more effective methods to control insecticide resistance in mosquito vectors. Worldwide geographical distribution of insecticide resistance in Ae. aegypti and Ae. albopictus by the available papers and map of the data for carbamates, organochlorines, organophosphates, pyrethroids, microbial and insect growth regulator insecticides were reviewed. Article data published up to December 2022 were investigated by searching the following databases: "Google Scholar", "PubMed", "Scopus", "SID" and "Web of Knowledge". The results showed that the susceptibility and resistance status of Ae. aegypti and Ae. albopictus to insecticides in the world is very diverse. Due to the importance of Ae. aegypti and Ae. albopictus in the transmission of mosquito-borne arboviruses, resistance management should be given more attention worldwide to prevent insecticide resistance in the arbovirus vector and replace the new approach for vector control.

Molecular identification of Leishmania major species in phlebotomine sand flies from Al Ahsa, Eastern KSA

ObjectivesCutaneous leishmaniasis (CL) is considered an overlooked public health threat in KSA. CL is endemic to several Saudi regions, including Al Ahsa City, Eastern KSA. To our knowledge, no prior molecular identification of Leishmania parasites in vectors in Al Ahsa has been published. The aim of this study was to perform molecular identification of Leishmania species in sand flies collected from Al Ahsa. MethodsThis cross-sectional study was conducted in Al Ahsa from July 2020 to May 2021. Sand flies were collected from the three areas with the highest rates of CL cases and sand flies, according to data from the Vector Borne Diseases Prevention Center in Al Ahsa. CDC miniature light traps and sticky traps were used to collect sand flies. Pools of 3–10 female sand flies were subjected to genomic DNA extraction. The extracted DNA was then amplified with a protocol targeting the Leishmania genus and using species-specific primers. For Leishmania species identification, a PCR-restriction fragment length polymorphism (PCR-RFLP) method was used. ResultsTen of 113 pools of samples tested positive for the Leishmania genus, according to our experimental protocol. Characterization of Leishmania species by PCR-RFLP established Leishmania major as the only species found in the collected sand flies. ConclusionThis is the first documentation of molecular identification of Leishmania species in phlebotomine sand flies in the Al Ahsa region. L. major was the only species identified in our study. Further comprehensive research investigating the vectors and reservoirs will be crucial to establish the dynamics of transmission of Leishmania in Al Ahsa.

Nanoparticles: A Potential and Effective Method to Control Insect-Borne Diseases.

Insects act as vectors to carry a wide range of bacteria and viruses that can cause multiple vector-borne diseases in humans. Diseases such as dengue fever, epidemic encephalitis B, and epidemic typhus, which pose serious risks to humans, can be transmitted by insects. Due to the absence of effective vaccines for most arbovirus, insect control was the main strategy for vector-borne diseases control. However, the rise of drug resistance in the vectors brings a great challenge to the prevention and control of vector-borne diseases. Therefore, finding an eco-friendly method for vector control is essential to combat vector-borne diseases. Nanomaterials with the ability to resist insects and deliver drugs offer new opportunities to increase agent efficacy compared with traditional agents, and the application of nanoagents has expanded the field of vector-borne disease control. Up to now, the reviews of nanomaterials mainly focus on biomedicines, and the control of insect-borne diseases has always been a neglected field. In this study, we analyzed 425 works of the literature about different nanoparticles applied on vectors in PubMed around keywords, such as"nanoparticles against insect," "NPs against insect," and "metal nanoparticles against insect." Through these articles, we focus on the application and development of nanoparticles (NPs) for vector control, discussing the lethal mechanism of NPs to vectors, which can explore the prospect of applying nanotechnology in the prevention and control of vectors.

Guide to equine exotic vectorborne diseases and their risks to UK horses

Background: Infectious diseases remain a constant threat to human and animal populations, with the potential for far‐reaching and diverse impacts on health, welfare, trade, livelihoods and the economy. Over recent years, many infectious diseases have increased in incidence and geographical range and this is the result of a multitude of factors, of which population expansion, globalisation and climate change are notable. With increased international connectivity, emergence and re‐emergence of exotic diseases have arisen on multiple occasions in the UK.Aim of the article: This article reviews the epidemiology, clinical presentation, diagnosis, control and prevention of the key equine vectorborne diseases. It also outlines the surveillance initiatives in place for detection of these diseases, and the current risk status they pose to the UK equine population.

Integrated vector management program in the framework of the COVID-19 pandemic in Medellin, Colombia

Introduction: The COVID-19 pandemic pressured health care systems to remain alert and active in their vector-borne disease control and prevention programs, leading to changes in vector control strategies in urban areas affected by dengue, Zika and chikungunya. Objective: To describe the adaptations made to the vector control and surveillance program in Medellín during the COVID-19 health emergency. Materials and methods: Once the health emergency started, biosecurity protocols were developed. Entomological surveillance was strengthened from the institutional environment instead of homes. Data was collected in Medellín from 2018 to 2021 during the vector control and surveillance program activities, which included epidemiological and entomovirological surveillance, entomological index survey, ovitrap monitoring, community mobilization, search and elimination of mosquito breading sites, and chemical control. These actions were adapted and/or increased to promote self-care among communities in total and partial confinement, and to develop prevention and control measures. Results: Mosquito monitoring was increased by 40% using ovitraps, entomological virological surveillance showed an increase in 2020 of 34,4% compared to 2019 and virtual media was used to keep and improve contact with the community. Conclusion: The COVID-19 pandemic had a significant impact on arbovirus prevention and control programs. The city of Medellín quickly adapted its entomo-virological surveillance activities, control measures, and the contact with the community during the pandemic, which allow the Integrated Vector Management program to remain active in the city.

Resistance to Pyrethroids in the Malaria Vector Anopheles albimanus in Two Important Villages in the Soconusco Region of Chiapas, Mexico, 2022

Chiapas State comprises the largest malaria foci from Mexico, and 57% of the autochthonous cases in 2021, all with Plasmodium vivax infections, were reported in this State. Southern Chiapas is at constant risk of cases imported due to migratory human flow. Since chemical control of vector mosquitoes is the main entomological action implemented for the prevention and control of vector-borne diseases, this work aimed to investigate the susceptibility of Anopheles albimanus to insecticides. To this end, mosquitoes were collected in cattle in two villages in southern Chiapas in July-August 2022. Two methods were used to evaluate the susceptibility: the WHO tube bioassay and the CDC bottle bioassay. For the latter, diagnostic concentrations were calculated. The enzymatic resistance mechanisms were also analyzed. CDC diagnostic concentrations were obtained; 0.7 μg/mL deltamethrin, 12 μg/mL permethrin, 14.4 μg/mL malathion, and 2 μg/mL chlorpyrifos. Mosquitoes from Cosalapa and La Victoria were susceptible to organophosphates and to bendiocarb, but resistant to pyrethroids, with mortalities between 89% and 70% (WHO), and 88% and 78% (CDC), for deltamethrin and permethrin, respectively. High esterase levels are suggested as the resistance mechanism involved in the metabolism of pyrethroids in mosquitoes from both villages. Mosquitoes from La Victoria might also involve cytochrome P450. Therefore, organophosphates and carbamates are suggested to currently control An. albimanus. Its use might reduce the frequency of resistance genes to pyrethroids and vector abundance and may impede the transmission of malaria parasites.

Rickettsia felis is an emerging human pathogen associated with cat fleas: A review of findings in Taiwan

Rickettsia felis is an emerging rickettsial agent principally associated with cat fleas (Ctenocephalides felis), formerly discovered in 1990. Since then, clinical cases of R. felis infection have been identified globally by specific DNA sequences in patients with undifferentiated febrile illness, including in Taiwan, but such evidence is limited. R. felis rickettsiosis is self-limiting and easily treated with doxycycline, but its diagnosis remains a challenge. Environmental risk factors for R. felis rickettsiosis have yet to be clearly demonstrated, and its transmission biology is incompletely understood. Cat fleas are naturally infected with R. felis at varying rates, and vector competence in the transmission of R. felis has been demonstrated in animal models, including dogs, which may serve as reservoir hosts. In northern Taiwan, despite ∼20% of cat fleas infesting companion animals consistently found to be infected with R. felis, only a few cases of potential R. felis infection have been identified through a retrospective serological investigation, though without molecular confirmation. Ecological studies have identified divergent R. felis-like organisms in different arthropod hosts, but these strains appear to serve as nonpathogenic endosymbionts. Although its association with disease is limited, we believe cat flea-borne R. felis warrants increased recognition in an aging population due to immunosenescence and the proximity of companion animals to the elderly. Adopting a One Health approach involving collaboration and communication between clinicians, veterinarians, public health practitioners, and environmental scientists will improve our knowledge about this neglected pathogen and promote the prevention and control of vector-borne diseases.

Use of Insect Promoters in Genetic Engineering to Control Mosquito-Borne Diseases.

Mosquito transgenesis and gene-drive technologies provide the basis for developing promising new tools for vector-borne disease prevention by either suppressing wild mosquito populations or reducing their capacity from transmitting pathogens. Many studies of the regulatory DNA and promoters of genes with robust sex-, tissue- and stage-specific expression profiles have supported the development of new tools and strategies that could bring mosquito-borne diseases under control. Although the list of regulatory elements available is significant, only a limited set of those can reliably drive spatial-temporal expression. Here, we review the advances in our ability to express beneficial and other genes in mosquitoes, and highlight the information needed for the development of new mosquito-control and anti-disease strategies.

Quantitative Trait Locus Determining the Time of Blood Feeding in Culex pipiens (Diptera: Culicidae).

Mosquitoes and other blood feeding arthropods are vectors of pathogens causing serious human diseases, such as Plasmodium spp. (malaria), Wuchereria bancrofti (lymphatic filariasis), Borrelia burgdorferi (Lyme disease), and viruses causing dengue, Zika, West Nile, chikungunya, and yellow fever. Among the most effective strategies for the prevention of vector-borne diseases are those aimed at reducing human-vector interactions, such as insecticide applications and insecticide-treated bed nets (ITNs). In some areas where ITNs are widely used, behavioral adaptations have resulted in mosquitoes shifting their time of blood feeding to earlier or later in the night when the bed nets are not being employed. Little is known about the genetic basis of these behavioral shifts. We conducted quantitative trait locus (QTL) analysis using two strains of Culex pipiens sensu lato with contrasting blood feeding behaviors, wherein the lab adapted Shasta strain blood feeds at any time of the day or night, while the newly established Trinidad strain feeds only at night. We identified a single locus on chromosome 2 associated with the observed variation in feeding times. None of the core clock genes period, timeless, clock, cycle, PAR-domain protein 1, vrille, discs overgrown, cryptochrome 1, or cryptochrome 2 were located within the QTL region. We then monitored locomotor behavior to determine if they differed in their flight activity. The highly nocturnal Trinidad strain showed little daytime activity while the day-feeding Shasta strain was active during the day, suggesting blood feeding behavior and flight activity are physiologically linked.

Laboratory evaluation of a new alphacypermethrin long-lasting insecticidal net against Anopheles culicifacies s.l.

Long-lasting insecticidal nets (LLINs) are being promoted by World Health Organization (WHO) as key vector control tool for the prevention and control of malaria and other vector-borne diseases. A laboratory study was conducted to evaluate the bio-efficacy of a new alphacypermethrin LN (HILNET®) against insecticide-susceptible Anopheles culicifacies s.l.. This study presents the observations on (a) regeneration time, the period required to regenerate insecticide in the LLIN after three consecutive WHO standard washes in a single day to deplete the insecticide on the net surface, and (b) wash resistance of the LLIN to retain bio-efficacy up to 20 repeated washes at intervals corresponding to the regeneration time in days. In the present evaluation, the regeneration time of HILNet® was determined as 2days. Wash resistance studies of HILNet® showed a knockdown rate of 100% up to 15 washes and 97% at the 20th wash and complied with the criteria of WHO knockdown rate of ≥ 95%. The mean active ingredient content from 0 to 20 washes was in the range of 5.8 to 6.04g/kg and met the WHO criteria of the product claim (± 25% g/kg). The insecticide un-impregnated control net has shown no detectable levels of alphacypermethrin. In this evaluation, HILNet® fulfilled the WHO laboratory (phase I) efficacy criteria based on the rates of knockdown up to 20 standard WHO washes.

Modified Mosquitoes for the Prevention and Control of Vector-Borne Diseases

Modified Mosquitoes for the Prevention and Control of Vector-Borne Diseases

Exploring the key anthropological drivers of and barriers to zoonotic malaria preventative behaviour in a community exposed to Plasmodium knowlesi infection in Malaysia: protocol for a qualitative study with a participatory research design

IntroductionPlasmodium knowlesi malaria is a zoonotic mosquito-borne disease with complex epidemiology. According to the WHO, the prevention and control of vector-borne diseases require community participation to increase coherence between malaria...