scholarly journals Vector microbiota manipulation by host antibodies: the forgotten strategy to develop transmission-blocking vaccines

2022 ◽  
Vol 15 (1) ◽  
Author(s):  
Apolline Maitre ◽  
Alejandra Wu-Chuang ◽  
Justė Aželytė ◽  
Vaidas Palinauskas ◽  
Lourdes Mateos-Hernández ◽  
...  
Keyword(s):  
Management Practices ◽  
Vector Competence ◽  
Control Measures ◽  
Immune Functions ◽  
Transmission Blocking ◽  
Host Interactions ◽  
Animal Pathogens ◽  
Tick Borne Encephalitis Virus ◽  
Hematophagous Arthropods ◽  
Transmission Blocking Vaccines

AbstractHuman and animal pathogens that are transmitted by arthropods are a global concern, particularly those vectored by ticks (e.g. Borrelia burgdorferi and tick-borne encephalitis virus) and mosquitoes (e.g. malaria and dengue virus). Breaking the circulation of pathogens in permanent foci by controlling vectors using acaricide-based approaches is threatened by the selection of acaricide resistance in vector populations, poor management practices and relaxing of control measures. Alternative strategies that can reduce vector populations and/or vector-mediated transmission are encouraged worldwide. In recent years, it has become clear that arthropod-associated microbiota are involved in many aspects of host physiology and vector competence, prompting research into vector microbiota manipulation. Here, we review how increased knowledge of microbial ecology and vector-host interactions is driving the emergence of new concepts and tools for vector and pathogen control. We focus on the immune functions of host antibodies taken in the blood meal as they can target pathogens and microbiota bacteria within hematophagous arthropods. Anti-microbiota vaccines are presented as a tool to manipulate the vector microbiota and interfere with the development of pathogens within their vectors. Since the importance of some bacterial taxa for colonization of vector-borne pathogens is well known, the disruption of the vector microbiota by host antibodies opens the possibility to develop novel transmission-blocking vaccines.

scholarly journals Identification of Novel Malaria Transmission-Blocking Vaccine Candidates

2021 ◽  
Vol 11 ◽  
Author(s):  
Eizo Takashima ◽  
Mayumi Tachibana ◽  
Masayuki Morita ◽  
Hikaru Nagaoka ◽  
Bernard N. Kanoi ◽  
...  
Keyword(s):  
Research And Development ◽  
Control Measures ◽  
Sub Saharan Africa ◽  
Parasite Transmission ◽  
Transmission Blocking ◽  
Vaccine Candidates ◽  
Malaria Vaccines ◽  
Sub Saharan ◽  
Transmission Blocking Vaccines ◽  
Transmission Blocking Vaccine

Control measures have significantly reduced malaria morbidity and mortality in the last two decades; however, the downward trends have stalled and have become complicated by the emergence of COVID-19. Significant efforts have been made to develop malaria vaccines, but currently only the RTS,S/AS01 vaccine against Plasmodium falciparum has been recommended by the WHO, for widespread use among children in sub-Saharan Africa. The efficacy of RTS,S/AS01 is modest, and therefore the development of more efficacious vaccines is still needed. In addition, the development of transmission-blocking vaccines (TBVs) to reduce the parasite transmission from humans to mosquitoes is required toward the goal of malaria elimination. Few TBVs have reached clinical development, and challenges include low immunogenicity or high reactogenicity in humans. Therefore, novel approaches to accelerate TBV research and development are urgently needed, especially novel TBV candidate discovery. In this mini review we summarize the progress in TBV research and development, novel TBV candidate discovery, and discuss how to accelerate novel TBV candidate discovery.

Climate resilience in rural Zambia: evaluating farmers’ response to El Niño-induced drought

2021 ◽  
pp. 1-23
Author(s):  
Federica Alfani ◽  
Aslihan Arslan ◽  
Nancy McCarthy ◽  
Romina Cavatassi ◽  
Nicholas Sitko
Keyword(s):  
El Niño ◽  
Management Practices ◽  
Unobserved Heterogeneity ◽  
El Nino ◽  
Control Measures ◽  
Data Set ◽  
Climate Resilience ◽  
Diversification Strategies ◽  
Household Incomes ◽  
Rural Zambia

Abstract This paper aims at identifying whether and how sustainable land management practices and livelihood diversification strategies have contributed to moderating the impacts of the El Niño-related drought in Zambia. This is done using a specifically designed survey called the El Niño Impact Assessment Survey, which is combined with the Rural Agricultural Livelihoods Surveys, as well as high resolution rainfall data at the ward level over 34 years. This unique panel data set allows us to control for the time-invariant unobserved heterogeneity to understand the impacts of shocks like El Niño, which are expected to become more frequent and severe as a result of climate change. We find that maize yields were substantially reduced and that household incomes were only partially protected from the shock thanks to diversification strategies. Mechanical erosion control measures and livestock diversification emerge as the only strategies that provided yield and income benefits under weather shock.

scholarly journals ITN—VIROINF: Understanding (Harmful) Virus-Host Interactions by Linking Virology and Bioinformatics

Viruses ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 766
Author(s):  
Winfried Goettsch ◽  
Niko Beerenwinkel ◽  
Li Deng ◽  
Lars Dölken ◽  
Bas E. Dutilh ◽  
...  
Keyword(s):  
Control Strategies ◽  
Fundamental Importance ◽  
Viral Growth ◽  
International Training ◽  
Host Interactions ◽  
Animal Pathogens ◽  
Interdisciplinary Nature ◽  
Common Goals

Many recent studies highlight the fundamental importance of viruses. Besides their important role as human and animal pathogens, their beneficial, commensal or harmful functions are poorly understood. By developing and applying tailored bioinformatical tools in important virological models, the Marie Skłodowska-Curie Initiative International Training Network VIROINF will provide a better understanding of viruses and the interaction with their hosts. This will open the door to validate methods of improving viral growth, morphogenesis and development, as well as to control strategies against unwanted microorganisms. The key feature of VIROINF is its interdisciplinary nature, which brings together virologists and bioinformaticians to achieve common goals.

scholarly journals Constraints to Pearl Millet (Pennisetum glaucum) Production and Farmers’ Approaches to Striga hermonthica Management in Burkina Faso

2021 ◽  
Vol 13 (15) ◽  
pp. 8460
Author(s):  
Armel Rouamba ◽  
Hussein Shimelis ◽  
Inoussa Drabo ◽  
Mark Laing ◽  
Prakash Gangashetty ◽  
...  
Keyword(s):  
Burkina Faso ◽  
Pearl Millet ◽  
Management Practices ◽  
Pennisetum Glaucum ◽  
Control Measures ◽  
Striga Hermonthica ◽  
Soil Conditions ◽  
Management Options ◽  
Central Plateau ◽  
South Central

Pearl millet (Pennisetum glaucum) is a staple food crop in Burkina Faso that is widely grown in the Sahelian and Sudano-Sahelian zones, characterised by poor soil conditions and erratic rainfall, and high temperatures. The objective of this study was to document farmers’ perceptions of the prevailing constraints affecting pearl millet production and related approaches to manage the parasitic weeds S. hermonthica. The study was conducted in the Sahel, Sudano-Sahelian zones in the North, North Central, West Central, Central Plateau, and South Central of Burkina Faso. Data were collected through a structured questionnaire and focus group discussions involving 492 participant farmers. Recurrent drought, S. hermonthica infestation, shortage of labour, lack of fertilisers, lack of cash, and the use of low-yielding varieties were the main challenges hindering pearl millet production in the study areas. The majority of the respondents (40%) ranked S. hermonthica infestation as the primary constraint affecting pearl millet production. Respondent farmers reported yield losses of up to 80% due to S. hermonthica infestation. 61.4% of the respondents in the study areas had achieved a mean pearl millet yields of <1 t/ha. Poor access and the high cost of introduced seed, and a lack of farmers preferred traits in the existing introduced pearl millet varieties were the main reasons for their low adoption, as reported by 32% of respondents. S. hermonthica management options in pearl millet production fields included moisture conservation using terraces, manual hoeing, hand weeding, use of microplots locally referred to as ‘zaï’, crop rotation and mulching. These management techniques were ineffective because they do not suppress the below ground S. hermonthica seed, and they are difficult to implement. Integrated management practices employing breeding for S. hermonthica resistant varieties with the aforementioned control measures could offer a sustainable solution for S. hermonthica management and improved pearl millet productivity in Burkina Faso.

Seasonal Nonstructural Carbohydrate Patterns in Dewberry (Rubus spp.) Roots

Weed Science ◽  
2021 ◽  
pp. 1-23
Author(s):  
Katherine M. Ghantous ◽  
Hilary A. Sandler
Keyword(s):  
Weed Management ◽  
Management Practices ◽  
Soluble Sugars ◽  
Leaf Expansion ◽  
Control Measures ◽  
Growth Stages ◽  
Phenological Stages ◽  
Long Term Storage ◽  
Nonstructural Carbohydrate ◽  
Fruit Maturity

Abstract Applying control measures when carbohydrate levels are low can decrease the likelihood of plant survival, but little is known about the carbohydrate cycles of dewberry (Rubus spp.), a problematic weed group on cranberry farms. Weedy Rubus plants were collected from areas adjacent to production beds on commercial cranberry farms in Massachusetts, two locations per year for two years. For each site and year, four entire plants were collected at five phenological stages: budbreak, full leaf expansion, flowering, fruit maturity, and after onset of dormancy. Root sections were analyzed for total nonstructural carbohydrate (TNC; starch, sucrose, fructose, and glucose). Overall trends for all sites and years showed TNC were lowest at full leaf expansion or flowering; when sampled at dormancy, TNC concentrations were greater than or equal to those measured at budbreak. Starch, a carbohydrate form associated with long-term storage, had low levels at budbreak, leaf expansion and/or flowering with a significant increase at fruit maturity and the onset of dormancy, ending at levels higher than those found at budbreak. The concentration of soluble sugars, carbohydrate forms readily usable by plants, was highest at budbreak compared to the other four phenological samplings. Overall, our findings supported the hypothesis that TNC levels within the roots of weedy Rubus plants can be predicted based on different phenological growth stages in Massachusetts. However, recommendations for timing management practices cannot be based on TNC cycles alone; other factors such as temporal proximity to dormancy may also impact Rubus plants recovery and further research is warranted. Late-season damage should allow less time for plants to replenish carbohydrate reserves (prior to the onset of dormancy), thereby likely enhancing weed management tactics effectiveness over time. Future studies should consider tracking the relationship between environmental conditions, phenological stages, and carbohydrate trends.

scholarly journals Performance Assessment of Erosion Remediation Measures and Proposal of The Best Management Practices for Erosion Control in Sebeya Catchment, Rwanda

2020 ◽  
Vol 3 (2) ◽  
Author(s):  
Félicien Majoro ◽  
Umaru Garba Wali ◽  
Omar Munyaneza ◽  
François-Xavier Naramabuye ◽  
Concilie Mukamwambali
Keyword(s):  
Soil Erosion ◽  
Best Management Practices ◽  
Management Practices ◽  
Soil Depth ◽  
Erosion Control ◽  
Control Measures ◽  
Tree Planting ◽  
Best Management ◽  
Remediation Measures ◽  
Soil Erosion Control

Soil erosion is an environmental concern that affects agriculture, wildlife and water bodies. Soil erosion can be avoided by maintaining a protective cover on the soil to create a barrier to the erosive agent or by modifying the landscape to control runoff amounts and rates. This research is focused on Sebeya catchment located in the Western Province of Rwanda. Sebeya catchment is one of the most affected areas by soil erosion hazards causing loss of crops due to the destruction of agricultural plots or riverbanks, river sedimentation and damages to the existing water treatment and hydropower plants in the downstream part of the river. The aims of this research were to assess the performance of erosion remediation measures and to propose the Best Management Practices (BMPs) for erosion control in Sebeya catchment. Using literature review, site visits, questionnaire and interviews, various erosion control measures were analyzed in terms of performance and suitability. Land slope and soil depth maps were generated using ArcGIS software. The interview results indicated that among the 22 existing soil erosion control measures, about 4.57% of farmers confirmed their existence while 95.43% expressed the need of their implementation in Sebeya catchment. Furthermore, economic constraints were found to be the main limitative factors against the implementation of soil erosion control measures in Sebeya catchment. Also, the majority of farmers suggest trainings and mobilization of a specialized technical team to assist them in implementing soil conservation measures and to generalize the application of fertilizers in the whole catchment. Finally, soil erosion control measures including agro-forestry, terraces, mulching, tree planting, contour bunds, vegetative measures for slopes and buffer zones, check dams, riverbanks stabilization were proposed and recommended to be implemented in Sebeya catchment. Keywords: Erosion control measures, Sebeya catchment, Rwanda

scholarly journals Directed evolution of Metarhizium fungus improves its biocontrol efficacy against Varroa mites in honey bee colonies

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jennifer O. Han ◽  
Nicholas L. Naeger ◽  
Brandon K. Hopkins ◽  
David Sumerlin ◽  
Paul E. Stamets ◽  
...  
Keyword(s):  
Directed Evolution ◽  
Honey Bee ◽  
Entomopathogenic Fungi ◽  
Management Practices ◽  
Abiotic Factors ◽  
Control Measures ◽  
Residual Effects ◽  
Effective Control ◽  
Great Promise ◽  
Bee Colonies

AbstractEntomopathogenic fungi show great promise as pesticides in terms of their relatively high target specificity, low non-target toxicity, and low residual effects in agricultural fields and the environment. However, they also frequently have characteristics that limit their use, especially concerning tolerances to temperature, ultraviolet radiation, or other abiotic factors. The devastating ectoparasite of honey bees, Varroa destructor, is susceptible to entomopathogenic fungi, but the relatively warm temperatures inside honey bee hives have prevented these fungi from becoming effective control measures. Using a combination of traditional selection and directed evolution techniques developed for this system, new strains of Metarhizium brunneum were created that survived, germinated, and grew better at bee hive temperatures (35 °C). Field tests with full-sized honey bee colonies confirmed that the new strain JH1078 is more virulent against Varroa mites and controls the pest comparable to current treatments. These results indicate that entomopathogenic fungi are evolutionarily labile and capable of playing a larger role in modern pest management practices.

Integrated modelling under uncertainty in watershed-level assessment and management

2007 ◽  
Vol 56 (8) ◽  
pp. 31-39 ◽  
Author(s):  
J.H. Ham ◽  
C.G. Yoon ◽  
K.W. Jung ◽  
J.H. Jang
Keyword(s):  
Water Quality ◽  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Watershed Management ◽  
Management Practices ◽  
Control Measures ◽  
Integrated Modelling ◽  
Quality Prediction ◽  
Water Quality Prediction ◽  
Modelling System

Uncertainty in water quality model predictions is inevitably high due to natural stochasticity, model uncertainty, and parameter uncertainty. An integrated modelling system (modified-BASINS) under uncertainty is described and demonstrated for use in receiving-water quality prediction and watershed management. A Monte Carlo simulation was used to investigate the effect of various uncertainty types on output prediction. Without pollution control measures in the watershed, the concentrations of total nitrogen (T-N) and total phosphorus (T-P) in the Hwaong Reservoir, considering three uncertainty types, would be less than about 4.4 and 0.23 mg L−1, respectively, in 2012, with 90% confidence. The effects of two watershed management practices, wastewater treatment plants (WWTP) and constructed wetlands (WETLAND), were evaluated. The combined scenario (WWTP + WETLAND) was the most effective at improving reservoir water quality, bringing concentrations of T-N and T-P in the Hwaong Reservoir to less than 3.4 and 0.14 mg L−1, 24 and 41% improvements, respectively, with 90% confidence. Overall, the Monte Carlo simulation in the integrated modelling system was practical for estimating uncertainty and reliable in water quality prediction. The approach described here may allow decisions to be made based on the probability and level of risk, and its application is recommended.

scholarly journals INVASIVE PLANTS - A BOON OR BANE TO THE LEPIDOPTERON FAUNA: CONSERVATION AND MANAGEMENT PLAN SUGGESTIONS

2017 ◽  
Vol 4 (1) ◽  
pp. 148-160
Author(s):  
Arjun C.P ◽  
Anoop V.K ◽  
Tijo K.J ◽  
Anoopkumar T.K ◽  
Roshnath R
Keyword(s):  
Invasive Species ◽  
Plant Species ◽  
Invasive Plants ◽  
Management Practices ◽  
Invasive Plant ◽  
Management Plan ◽  
Control Measures ◽  
Pteridium Aquilinum ◽  
Native Flora ◽  
Long Run

Butterfly diversity was recorded from Nov (2013) - May (2014) in Pookode region. A total number of 128 species recorded from the five families; Nymphalidae (46 species) Lycaenidae (28 species), Hesperiidae (22 species), Pieridae (17 species) and Papilionidae (15 species) respectively. During the survey invasive plant species were also recorded. There were 36 species of invasive plants from 18 families identified from the study area. More butterflies were attracted towards nectar offering invasive plants. Chromolaena odorata, Ipomea cairica, Lantana camara, Merremia vitifolia, Mikania micrantha, Mimosa diplotricha, Pennisetumpolystachyon, Pteridium aquilinum, Quisqualis indica and Sphagneticola trilobata were the major invasive plants found in the Pookode region and their flower attracts butterfly for pollination. Even though nectar offered by the plants are supportive for growth, in long run these species can affect butterfly population bydeclining native host larval plant species for butterfly reproduction. Invasive species compete with the native flora and reduce its population. Management practices like physical, chemical and modern bio control measures could be used for eradicating of invasive plants. Wise use of invasive plants for other economical purpose such as bio-fuel, medicinal purpose, bio-pesticide and handicraft could be suggested. Successful management of invasive species are needed for conserving Lepidoptera fauna and other native biota of the area.

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