scholarly journals Dynamics of a combined medea-underdominant population transformation system

2014 ◽  
Author(s):  
Chaitanya Gokhale ◽  
Richard Guy Reeves ◽  
Floyd A Reed
Keyword(s):  
Theoretical Modelling ◽  
Low Frequencies ◽  
High Frequencies ◽  
Vector Borne Diseases ◽  
Novel Technology ◽  
Popu Lations ◽  
Insect Populations ◽  
Vector Borne ◽  
Transformation Systems ◽  
Modelling Approach

Transgenic constructs intended to be stably established at high frequencies in wild popu- lations have been demonstrated to “drive” from low frequencies in experimental insect populations. Link- ing such population transformation constructs to genes which render them unable to transmit pathogens could eventually be used to stop the spread of vector-borne diseases like malaria and dengue. Generally, population transformation constructs with only a single transgenic drive mechanism have been envisioned. Using a theoretical modelling approach we describe the predicted properties of a construct combining autosomal Medea and underdominant population transformation systems. We show that when combined they can exhibit synergistic properties which in broad circumstances surpass those of the single systems. With combined systems, intentional population transformation and its reversal can be achieved readily. Combined constructs also enhance the capacity to geographically restrict transgenic constructs to targeted populations. It is anticipated that these properties are likely to be of particular value in attracting regulatory approval and public acceptance of this novel technology.

scholarly journals Wolbachia cifB induces cytoplasmic incompatibility in the malaria mosquito

2021 ◽  
Author(s):  
Kelsey L Adams ◽  
Daniel G. Abernathy ◽  
Bailey C. Willett ◽  
Emily K. Selland ◽  
Maurice A. Itoe ◽  
...  
Keyword(s):  
Cytoplasmic Incompatibility ◽  
Control Strategies ◽  
Relative Role ◽  
Vector Borne Diseases ◽  
Limited Success ◽  
Insect Populations ◽  
Vector Borne ◽  
Female Germline ◽  
Major Malaria Vector

Wolbachia infections are a fascinating example of reproductive parasitism with strong potential to combat vector-borne diseases, due to their combined ability to spread in insect populations and block pathogen replication. Though the Wolbachia factors mediating the notable reproductive manipulation cytoplasmic incompatibility (CI) have now been identified as prophage WO genes cifA and cifB, the relative role of these genes is still intensely debated, with different models claiming that CI requires either both factors or cifB alone. Here we investigated whether cifA and cifB are sufficient to induce conditional sterility in the major malaria vector Anopheles gambiae, a species that appears to have limited susceptibility to invasion by Wolbachia. We report that CI can be fully recapitulated in these mosquitoes, and that cifB is sufficient to cause this reproductive manipulation. cifB-induced sterility is fully rescued by high levels of cifA expression in females. Surprisingly, however, when cifA is highly expressed in males alongside cifB, the CI phenotype is attenuated. cifB strongly impairs fertility also when expressed in the female germline, again mitigated by cifA. These data support a system whereby cifB and cifA must be fine-tuned to exercise CI and rescue, respectively, possibly explaining the limited success of Wolbachia at invading Anopheles. Our findings pave the way towards facilitating Wolbachia infections in anopheline vectors, for use in malaria control strategies.

scholarly journals Physiology and ecology together regulate host and vector importance for Ross River virus and other vector-borne diseases

2021 ◽  
Author(s):  
Morgan P. Kain ◽  
Eloise B. Skinner ◽  
Andrew F. van den Hurk ◽  
Hamish McCallum ◽  
Erin A. Mordecai
Keyword(s):  
Host Species ◽  
Direct Application ◽  
Ross River Virus ◽  
Vertebrate Species ◽  
Ecological Traits ◽  
Vector Borne Diseases ◽  
Community Transmission ◽  
Vector Borne ◽  
Urban Cycle ◽  
Modelling Approach

AbstractIdentifying the key vector and host species driving transmission is notoriously difficult for vector-borne zoonoses, but critical for disease control. Here, we present a general approach for quantifying the role hosts and vectors play in transmission that integrates species’ physiological competence with their ecological traits. We apply this model to the medically important arbovirus Ross River virus (RRV), in Brisbane, Australia. We found that vertebrate species with high physiological competence weren’t the most important for community transmission. Instead, we estimated that humans (previously overlooked as epidemiologically important hosts) potentially play an important role in RRV transmission, in part, because highly competent vectors readily feed on them and are highly abundant. By contrast, vectors with high physiological competence were also important for community transmission. Finally, we uncovered two potential transmission cycles: an enzootic cycle involving birds and an urban cycle involving humans. This modelling approach has direct application to other zoonotic arboviruses.

The Spread of Mosquito Borne Disease – Is Climate Change Beginning to Bite?

2019 ◽  
Vol 30 (5) ◽  
pp. 192-194
Author(s):  
John (Luke) Lucas
Keyword(s):  
Climate Change ◽  
Vector Borne Diseases ◽  
Vector Borne

The author considers the threat to vector-borne diseases in the light of climate change.

The Scientific Basis for the Prevention of Zooanthroponoze Vector-Borne Diseases Spread by Parasitic Arthropods of the Center of the East European Plain

2020 ◽  
Vol 14 (1) ◽  
pp. 81-88
Author(s):  
Fedor I. Vasilevich ◽  
Anna M. Nikanorova
Keyword(s):  
Mathematical Models ◽  
Culex Pipiens ◽  
Preventive Measures ◽  
Mosquito Species ◽  
Natural Habitat ◽  
Piperonyl Butoxide ◽  
East European Plain ◽  
Vector Borne Diseases ◽  
Vector Borne ◽  
Kaluga Region

The purpose of the research is development of preventive measures against zooanthroponoze vector-borne diseases spread by parasitic arthropods in the Kaluga Region. Materials and methods. The subject of the research was Ixodidae, mosquitoes, and small mammals inhabiting the Kaluga Region. The census of parasitic arthropods was carried out on the territory of all districts of the Kaluga Region and the city of Kaluga. Open natural habitat and human settlements were investigated. Weather conditions from 2013 to 2018 were also taken into account. For the purposes of the study, we used standard methods for capturing and counting arthropods and mouse-like rodents. In order to obtain mathematical models of small mammal populations, a full factorial experiment was conducted using the collected statistical data. In-process testing of the drug based on s-fenvalerate and piperonyl butoxide were carried out under the conditions of the agricultural collective farm “Niva” of the Kozelsky District, the Kaluga Region, and LLC “Angus Center of Genetics” of the Babyninsky District, the Kaluga Region. Results and discussion. In the Kaluga Region, two species of ixodic ticks are found, namely, Ixodes ricinus and Dermacentor reticulatus, which have two activity peaks. Mosquito may have 3-4 generations in a year in the Kaluga region. The most common mosquito species in the Kaluga Region are Aedes communis, Ae. (Och.) togoi and Ae. (Och.) diantaeus, Culex pipiens Culex Linnaeus, 1758 (Diptera, Culicidae) (Culex pipiens): Cx. pipiens f. pipiens L. (non-autogenic form) and Cx. p. f. molestus Fors. (autogenic form), which interbreed, and reproductively isolated in the Region. The developed mathematical models make it possible to quantify the risks of outbreaks of zooanthroponoze vector-borne diseases without the cost of field research, and allow for rational, timely and effective preventive measures. Medications based on s-fenvalerate and piperonyl butoxide and based on cyfluthrin showed high insecto-acaricidal efficacy and safety.

Current Challenges in the Development of Vaccines and Drugs Against Emerging Vector-borne Diseases

2019 ◽  
Vol 26 (16) ◽  
pp. 2974-2986 ◽  
Author(s):  
Kwang-sun Kim
Keyword(s):  
New Host ◽  
In Vivo Models ◽  
Vector Borne Diseases ◽  
Novel Drugs ◽  
Huge Impact ◽  
Tick Borne Disease ◽  
Vector Borne ◽  
Living Organisms

Vectors are living organisms that transmit infectious diseases from an infected animal to humans or another animal. Biological vectors such as mosquitoes, ticks, and sand flies carry pathogens that multiply within their bodies prior to delivery to a new host. The increased prevalence of Vector-Borne Diseases (VBDs) such as Aedes-borne dengue, Chikungunya (CHIKV), Zika (ZIKV), malaria, Tick-Borne Disease (TBD), and scrub typhus has a huge impact on the health of both humans and livestock worldwide. In particular, zoonotic diseases transmitted by mosquitoes and ticks place a considerable burden on public health. Vaccines, drugs, and vector control methods have been developed to prevent and treat VBDs and have prevented millions of deaths. However, development of such strategies is falling behind the rapid emergence of VBDs. Therefore, a comprehensive approach to fighting VBDs must be considered immediately. In this review, I focus on the challenges posed by emerging outbreaks of VBDs and discuss available drugs and vaccines designed to overcome this burden. Research into promising drugs needs to be upgraded and fast-tracked, and novel drugs or vaccines being tested in in vitro and in vivo models need to be moved into human clinical trials. Active preventive tactics, as well as new and upgraded diagnostics, surveillance, treatments, and vaccination strategies, need to be monitored constantly if we are to manage VBDs of medical importance.

scholarly journals Molecular survey of vector-borne diseases in two groups of domestic dogs from Lisbon, Portugal

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Ana Mafalda Dordio ◽  
Relja Beck ◽  
Telmo Nunes ◽  
Isabel Pereira da Fonseca ◽  
Jacinto Gomes
Keyword(s):  
Clinical Status ◽  
Molecular Methods ◽  
Hepatozoon Canis ◽  
Clinical Approach ◽  
Limited Information ◽  
Vector Borne Diseases ◽  
Wide Range ◽  
Other Information ◽  
Southern Portugal ◽  
Vector Borne

Abstract Background Canine vector-borne diseases (CVBDs) are caused by a wide range of pathogens transmitted by arthropods. They have been an issue of growing importance in recent years; however, there is limited information about the vector-borne pathogens circulating in Portugal. The aim of the present study was to detect canine vector-borne bacteria and protozoa of veterinary and zoonotic importance using molecular methods. Methods One hundred and forty-two dogs from Lisbon, southern Portugal, were tested: 48 dogs from a veterinary hospital clinically suspected of vector-borne diseases and 94 apparently healthy dogs from shelters. Anaplasma spp./Ehrlichia spp., Babesia/Theileria spp., Hepatozoon spp., and Mycoplasma spp. infections were detected by PCR from blood samples and examined under light microscopy. Other information including clinical status and diagnostic test results were collected for each animal. Results Infections were detected by PCR in 48 (33.80%) dogs. Single infections were found in 35 dogs (24.64%), and co-infections were found in 13 (9.15%) dogs. Twenty-nine (20.42%) dogs were positive for Hepatozoon spp., 15 (10.56%) for Mycoplasma spp., 11 (7.75%) for Anaplasma spp./Ehrlichia spp., and six (4.21%) for Babesia spp. DNA sequencing was used to identify Babesia vogeli (2.81%), Babesia canis (1.40%), Hepatozoon canis (20.42%), Mycoplasma haematoparvum (2.11%), Mycoplasma haemocanis (8.45%), Anaplasma platys (7.04%), and Ehrlichia canis (0.70%). Conclusions This is the first molecular identification of B. canis and M. haematoparvum in dogs from southern Portugal. This study highlights the importance of molecular methods to identify CVBD pathogens in endemic areas and helps to guide the clinical approach of veterinarians in practice.

scholarly journals Reptile vector-borne diseases of zoonotic concern

2021 ◽  
Author(s):  
Jairo Alfonso Mendoza-Roldan ◽  
Miguel Angel Mendoza-Roldan ◽  
Domenico Otranto
Keyword(s):  
Vector Borne Diseases ◽  
Vector Borne
Sign in / Sign up

Export Citation Format

Share Document