scholarly journals Additional evidence on the efficacy of different Akirin vaccines assessed on Anopheles arabiensis (Diptera: Culicidae)

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Blaženka D. Letinić ◽  
Marinela Contreras ◽  
Yael Dahan-Moss ◽  
Ingrid Linnekugel ◽  
José de la Fuente ◽  
...  
Keyword(s):  
Vector Control ◽  
Aedes Albopictus ◽  
Malaria Vector ◽  
Vaccine Efficacy ◽  
Anopheles Arabiensis ◽  
Vaccine Development ◽  
Target Antigen ◽  
Control Methods ◽  
Protective Response ◽  
Current Vector

Abstract Background Anopheles arabiensis is an opportunistic malaria vector that rests and feeds outdoors, circumventing current indoor vector control methods. Furthermore, this vector will readily feed on both animals and humans. Targeting this vector while feeding on animals can provide an additional intervention for the current vector control activities. Previous results have displayed the efficacy of using Subolesin/Akirin ortholog vaccines for the control of multiple ectoparasite infestations. This made Akirin a potential antigen for vaccine development against An. arabiensis. Methods The efficacy of three antigens, namely recombinant Akirin from An. arabiensis, recombinant Akirin from Aedes albopictus, and recombinant Q38 (Akirin/Subolesin chimera) were evaluated as novel interventions for An. arabiensis vector control. Immunisation trials were conducted based on the concept that mosquitoes feeding on vaccinated balb/c mice would ingest antibodies specific to the target antigen. The antibodies would interact with the target antigen in the arthropod vector, subsequently disrupting its function. Results All three antigens successfully reduced An. arabiensis survival and reproductive capacities, with a vaccine efficacy of 68–73%. Conclusions These results were the first to show that hosts vaccinated with recombinant Akirin vaccines could develop a protective response against this outdoor malaria transmission vector, thus providing a step towards the development of a novel intervention for An. arabiensis vector control. Graphic Abstract

scholarly journals Human Antibody Response to Anopheles Saliva for Comparing the Efficacy of Three Malaria Vector Control Methods in Balombo, Angola

PLoS ONE ◽  
2012 ◽  
Vol 7 (9) ◽  
pp. e44189 ◽  
Author(s):  
Laura Brosseau ◽  
Papa Makhtar Drame ◽  
Patrick Besnard ◽  
Jean-Claude Toto ◽  
Vincent Foumane ◽  
...  
Keyword(s):  
Antibody Response ◽  
Vector Control ◽  
Malaria Vector ◽  
Malaria Vector Control ◽  
Human Antibody ◽  
Control Methods

scholarly journals Semi Field Trial Competitive Power Married Made Sterile Aedes Albopictus as Method of Vector Control: A Current Vector Controlling Method

2019 ◽  
Vol 3 (1) ◽  
pp. 172-180
Author(s):  
Ahmad Rosyadi ◽  
Ahmad Sehabudin ◽  
Ariel Rifayat
Keyword(s):  
Aedes Aegypti ◽  
Vector Control ◽  
Aedes Albopictus ◽  
Case Fatality Rate ◽  
Case Fatality ◽  
Hemorrhagic Fever ◽  
Current Vector ◽  
Disease Vector ◽  
Very High ◽  
A Current

Aedes albopictus is a plant that causes Dengue Hemorrhagic Fever is not as prevalent as Aedes Aegypti is not a disease given by Aedes albopictus mosquito is not much different from Aedes Aegypti mosquito. The Case Fatality Rate (CFR) of Dengue Fever is very high in Indonesia, at 41.4% at the beginning of dengue cases in Indonesia. Innovation continues to create for disease vector control to break the chain of disease. The use of sterile insect techniques is a useful thing in the things that need to be socialized in the community.

scholarly journals Phenotypic and molecular analysis of insecticide resistance in Aedes albopictus populations from Greece

2020 ◽  
Author(s):  
Sofia Balaska ◽  
Emmanouil Alexandros Fotakis ◽  
Ilias Kioulos ◽  
Linda Grigoraki ◽  
Spyridoula Mpellou ◽  
...  
Keyword(s):  
Insecticide Resistance ◽  
Vector Control ◽  
Molecular Analysis ◽  
Aedes Albopictus ◽  
Pyrethroid Resistance ◽  
Disease Outbreaks ◽  
Control Methods ◽  
Resistance Mutations ◽  
Control Programs ◽  
Southern European Countries

Abstract Background: Aedes albopictus has a well-established presence in southern European countries, associated with recent disease outbreaks (e.g. Chikungunya). Development of insecticide resistance in the vector is a major concern as it’s control mainly relies on the use of biocides. Data on the specie’s resistance status is essential for efficient and sustainable control. Methods: We investigated the insecticide resistance status of several Ae. albopictus populations from Greece. Bioassays were performed against diflubenzuron (DFB), B. thuringiensis var. israelensis (Bti), deltamethrin and malathion. Molecular analysis of known insecticide resistance loci was performed, i.e. voltage-gated sodium channel (VGSC) mutations associated with pyrethroid resistance; presence and frequency of carboxylesterases 3 (CCEae3a) and 6 (CCEae6a) gene amplification associated with organophosphate (OP) resistance and; chitin synthase-1 (CHS-1) for the possible presence of DFB resistance mutations. Results: Bioassays showed full susceptibility to DFB, Bti and deltamethrin, but resistance against the OP malathion. VGSC analysis revealed a widespread distribution of mutations F1534C (in all populations, with allelic frequencies between 6.6% - 68.3%), and I1532T (in 6 populations), but absence of V1016G. CCE gene amplifications were recorded in 8 out of 11 populations. Co-presence of mutation F1534C and CCEae3a amplification was reported in a subgroup of samples. No mutations at the CHS locus I1043 were detected. Conclusions: The results indicate: (i) the suitability of larvicides DFB and Bti for Ae. albopictus control in Greece, (ii) a possible incipient pyrethroid resistance due to the presence of kdr mutations and (iii) a possible reduced efficacy of OPs, in a scenario of re-introducing them for vector control. The study highlights the need for systematic resistance monitoring for developing and implementing appropriate evidence-based control programs. Key words: diagnostic, arbovirus, mosquito tiger, insecticide resistance, vector control, Europe

scholarly journals Evaluation of Larvicidal Activities of Parthenium Hysterophorus L. Against Anopheles Arabiensis (Diptera: Culicidae), the Major Malaria Vector in Ethiopia

2020 ◽  
Author(s):  
Mihretu Nigatu Tarekegn ◽  
Yitbarek Wolde-hawariat ◽  
Sisay Dugassa ◽  
Habte Tekie
Keyword(s):  
Petroleum Ether ◽  
Vector Control ◽  
Malaria Vector ◽  
Anopheles Arabiensis ◽  
Larval Mortality ◽  
Indoor Residual Spraying ◽  
Parthenium Hysterophorus ◽  
Mortality Data ◽  
Root Extract ◽  
Larvicidal Activities

Abstract Background: Malaria is a leading public health problem in Ethiopia despite the implementation of effective indoor vector control strategies over several decades. Vector control operations in the country largely depend on the application of Indoor Residual Spraying (IRS) of synthetic insecticides and Long Lasting Insecticidal Nets (LLINs) which resulted in a significant reduction in the malaria burden. The spread of resistance to insecticides in these indoor vector control tools in vector species is a serious challenge. Alternatively, reports indicate that botanicals which are relatively safe possess toxic compounds with high larvicidal activities. However, there are limited evidences on the larvicidal effect of botanicals against the malaria vectors, Anopheles arabiensis . This study aimed to evaluate the larvicidal activities of the extracts of the roots, stems, and leaves of Parthenium hysterophorus against the 4 th instar larvae of An. arabiensis . Methods: Field collected leaves, stems and root parts of P. hysterophorus were dried and separately ground to powder and extracted in petroleum ether, hexane, acetone, and ethanol solvents. The extracts were concentrated using a Rota evaporator, and stock solutions were subject to serial dilutions for use as test concentrations. Laboratory reared 4 th instar larvae of An. arabiensis were used for the larvicidal bioassays. Mortality data were subjected probit analysis to determine LC 50 and LC 90 of the extracts. Results: The results showed that there were significant differences in percentage larval mortalities (P<0.05) among different concentrations of the leaf, stem, and root solvent extracts, respectively. Hexane extracts of leaves and stem of P. hysterophorus at 480ppm caused the highest mortality of 4 th larval instar of An. arabiensis (85% and 96.7%, respectively) compared to those of ethanolic, acetone, and petroleum ether extracts of these plant parts. Petroleum ether extracts of the root of P. hysterophorus were the most effective in causing very high larval mortality at 360ppm and 480ppm (98.3%). The LC 50 value of petroleum ether root extract (10.7ppm) and LC 90 value of petroleum ether root extract (105.5ppm) were significantly lower than those of ethanol, acetone, and hexane root extracts, respectively. Conclusion: Petroleum ether root extract of P. hysterophorus has remarkably high larvicidal potential against 4 th instar larvae of An. arabiensis which could be exploited for malaria vector control. Further studies on the larvicidal efficacy of the extracts under field conditions and identification of the bioactive components in the root parts of this weed plant are recommended.

scholarly journals Estimates of the population size and dispersal range of Anopheles arabiensis in Northern KwaZulu-Natal, South Africa: implications for a planned pilot programme to release sterile male mosquitoes

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Maria L. Kaiser ◽  
Oliver R. Wood ◽  
David Damiens ◽  
Basil D. Brooke ◽  
Lizette L. Koekemoer ◽  
...  
Keyword(s):  
South Africa ◽  
Vector Control ◽  
Population Size ◽  
Malaria Vector ◽  
Anopheles Arabiensis ◽  
Dispersal Distance ◽  
Successful Implementation ◽  
Sterile Male ◽  
Mark Release Recapture ◽  
The Right

Abstract Background Anopheles arabiensis is a major malaria vector, recently implicated as contributing to ongoing residual malaria transmission in South Africa, which feeds and rests both indoors and outdoors. This species is, therefore, not effectively targeted using core malaria vector control interventions alone. Additionally, increasing resistance to available insecticides necessitates investigations into complementary non-insecticide-based vector control methods for outdoor-resting mosquitoes. The feasibility of the sterile insect technique (SIT) as a complementary vector control intervention is being investigated in South Africa. Successful implementation of an SIT programme largely depends on inundating a target insect population with sterilized laboratory-bred males. Therefore, knowledge of the native population size and dispersal ability of released sterile laboratory-reared males is critical. In this study, we estimated the male An. arabiensis population size and the dispersal of released males in an area targeted for a pilot sterile male release programme. Methods Three separate releases were performed within a 2-year period. Approximately 5000–15,000 laboratory-reared male An. arabiensis (KWAG) were produced and marked for mark–release–recapture experiments. To recapture released mosquitoes, cloth tubes were deployed in widening concentric circles. The average dispersal distance of released males was calculated and the wild male An. arabiensis population size was estimated using two Lincoln index formulae. The natural population was sampled concurrently and Anopheles species diversity examined. Results The Anopheles gambiae complex and An. funestus group species made up the majority of wild collections along with other anophelines. The An. arabiensis population size was estimated to be between 550 and 9500 males per hectare depending on time of year, weather conditions and method used. Average dispersal distance of marked males ranged from 58 to 86 m. Marked males were found in swarms with wild males, indicating that laboratory-reared males are able to locate and participate in mating swarms. Conclusions It was logistically feasible to conduct mark–release–recapture studies at the current scale. The population size estimates obtained may provide a guideline for the initial number of males to use for a pending SIT pilot trial. It is promising for future SIT trials that laboratory-reared marked males participated in natural swarms, appearing at the right place at the right time.

Community Knowledge, Attitude and Practices on Malaria Vector Control Strategies in Lagos State, South-West Nigeria

2021 ◽  
Author(s):  
Ahmed I Omotayo ◽  
Adeolu T Ande ◽  
Adedayo O Oduola ◽  
Abiodun K Olakiigbe ◽  
Aishat K Ghazali ◽  
...  
Keyword(s):  
Vector Control ◽  
Malaria Vector ◽  
Indoor Residual Spraying ◽  
Sub Saharan Africa ◽  
Malaria Vector Control ◽  
Control Methods ◽  
Level Of Education ◽  
Attitude And Practice ◽  
South West ◽  
Sub Saharan

Abstract Malaria is a leading public health challenge causing mortality and morbidity in sub-Saharan Africa. Prominent malaria vector control methods employed in sub-Saharan Africa include Long Lasting Insecticide Nets (LLINs) and Indoor Residual spraying (IRS). This study investigated knowledge, attitude and practices (KAP) of malaria vector control methods in Lagos, South-West Nigeria. Structured questionnaires were employed for the cross-sectional survey which was carried out between May and August 2018. Multi-stage sampling technique was used to select Lagos Mainland, Kosofe, and Ojo local government areas (LGAs). Five hundred and twenty questionnaires were used for the study. Data were analyzed for descriptive statistics, whereas χ 2 was used to determine influence of respondents’ LGA, level of education and type of dwelling on respondents’ attitude and practice. Respondents’ LGAs have no significant impact on attitude and practice to malaria vector control methods. However, ‘level of education’ as well as ‘type of dwelling structure’ impacted significantly on some practices and attitude. Basically, IRS is the major tool employed in malaria vector control, but sometimes it is used in combination with other methods. A good number of residents also use LLINs. ‘Choice of method’ employed is mainly based on the effectiveness of method. General perception about LLINs and IRS is that they are effective, cheap and safer. Considering the widespread use of IRS and LLINs for malaria vector control in Lagos, implementation of malaria control programs should consider KAP to these two strategies.

scholarly journals Heritability and phenotypic plasticity of biting time behaviors in the major African malaria vector Anopheles arabiensis

2021 ◽  
Author(s):  
Nicodem James Govella ◽  
Paul C D Johnson ◽  
Gerry F Killeen ◽  
Heather M Ferguson
Keyword(s):  
Phenotypic Plasticity ◽  
Malaria Vector ◽  
Anopheles Arabiensis ◽  
Mosquito Vector ◽  
Control Methods ◽  
Insecticide Treated Nets ◽  
Field System ◽  
Relative Contribution ◽  
Outdoor Biting ◽  
Biting Time

Use of Insecticide Treated Nets for malaria control has been associated with shifts in mosquito vector feeding behavior including earlier and outdoor biting on humans. The relative contribution of phenotypic plasticity and heritability to these behavioral shifts is unknown. Elucidation of the mechanisms behind these shifts is crucial for anticipating impacts on vector control. We used a novel portable semi-field system (PSFS) to experimentally measure heritability of biting time in the malaria vector Anopheles arabiensis in Tanzania. In PSFS assays, the biting time of F2 offspring (early: 18:00-21:00, mid: 22:00-04:00 or late: 05:00-07:00) was significantly associated with that of their wild-caught F0 grandmothers, corresponding to an estimated heritability of 0.30 (95% CI: 0.20, 0.41). F2 from early-biting F0 were more likely to bite early than F2 from mid or late late-biting F0. Similarly, the probability of biting late was higher in F2 derived from mid and late-biting F0 than from early-biting F0. Our results indicate that variation in biting time is attributable to additive genetic variation. Selection can therefore act efficiently on mosquito biting times, highlighting the need for control methods that target early and outdoor biting mosquitoes.

scholarly journals Community’s Knowledge, Attitudes and Practices towards Malaria Vector Control Methods in Ruhango district, Rwanda

2021 ◽  
Vol 6 (4) ◽  
Keyword(s):  
Vector Control ◽  
Malaria Vector ◽  
Control Measures ◽  
Malaria Vector Control ◽  
Control Methods ◽  
Good Practices ◽  
Attitudes And Practices ◽  
Positive Attitudes ◽  
Level Of Knowledge ◽  
Knowledge Attitudes And Practices

Background: Malaria occurs mostly in poor tropical and subtropical areas of the world and still a leading cause of illness and death. This study aimed to explore the community knowledge, attitudes and practices towards malaria vector control methods in Rwanda. Methods: This research was conducted under community-based cross-sectional study. Study was conducted in Ruhango district, located in South province of Rwanda. A number of 385 participants were selected using a two-stage randomized cluster sampling procedure and subjected to a tested structured questionnaire for data collection. The data were coded and entered using Kobo Collect Toolbox, and transferred to SPSS for statistical analysis. Results: More than a half of respondents were females (57.7%), married (69.4%), had attended school (89.4%) and 89.6% were farmers. The overall knowledge score showed that 41.0% had low knowledge about malaria vector control methods. Overall, 33.8% of the respondents had positive attitudes towards MVCM. The overall practice score indicated 24.7% of respondents had good on MVCM. People with high level of knowledge towards malaria vector control methods were less likely to have good practices on malaria vector control methods than people with medium and low level of knowledge towards MVCM (OR=0.04; 95%CI: [0.005-0.30]; p<0.001) and that people with positive attitudes were 1.97 times more likely having good practices than people with neutral and negative attitudes towards malaria vector control methods (OR=1.97; 95%CI: [1.08-3.59]; p<0.001). Conclusion: Malaria vector control campaigns accompanied with education for behavioural change should be considered to ensure householders’ participation and cooperation in the Integrated Vector Management (IVM) programme. Moreover, continuous evaluation and monitoring of IVM as well as conducting more surveys on KAP are recommended to improve malaria control measures and to identify indicators for effective, successful, and sustainable malaria elimination programme.

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