Mosquitoes bite: A Zika story on vector management and gene drives.

Parasitology Today, 1990

Transgenic mosquitoes may provide a new way of dealing with the old problem of diseases transmitted by insects. Although many technical, and perhaps ethical, problems associated with the wild-release of transgenic insects have yet to be overcome, Julian Crampton and colleagues explore the potential of this technology in the continuing battle to control insect-borne disease.

EMBO reports, 2016

More than 80% of the global populace lives in regions at a risk of at least one major vectorborne disease and more than 700,000 people die from vector-borne diseases in every year which is a big public concern. Collectively, these diseases cause massive economic losses and may perhaps hamper the development activities. As there are inadequate specific therapeutic drugs and no reliable vaccines for malaria or dengue, the World Health organization (WHO) is supporting and promoting the urgent need for new beneficial tools and technology to combat vector-borne diseases including genetically modified mosquitoes (GMM). For many, genetic engineering technologies offer a promising tool to control vector-borne infectious diseases. Nevertheless, the most recent releases of the first genetically modified (GM) mosquitoes into the wild have triggered intense debates. Recent advancements in genetic engineering technology, increased by the innovation of new molecular tools such as Insects carrying Dominant Lethals (RIDL) technology and CRISPER, have transformed the field of genetic engineering. These technologies developed several novel methods for the control of vector and pest insects. According to their genetic composition, these tools can be adjusted to impose different grades of impact on the targeted populations. As expected, several ecologists expressed concerns about the possible accidental side-effects on releasing modified flying insects on the bigger ecosystem. Here, we review some of the most recent ongoing genetic control innovations, their molecular mechanisms and performance, and emphasizing the sustainability potentials of such innovations.

With the sequencing of the Anopheles gambiae genome (Holt et al., 2002) the opportunity to develop genetically modified mosquitoes became a reality and a series of laboratory tests and trials have since explored various possibilities of population control through population suppression. The aims of this paper are to review the current and recent research relating to transgenic mosquitoes especially in relation to their possible future applications and efficacy as disease-vector control mechanisms. The paper will also consider some of the potential and incipient risks associated with the release of genetically modified mosquitoes. By looking at the dispersal and distribution of wild type mosquitoes coupled with human movement and global climate change this paper aims to present the implications of transgenic mosquitoes in relation to existing dispersal modeling.

Bridging laboratory and field research for genetic control of disease vectors

Advances in transgenic technology have allowed the development of genetically transformed insects that have reduced ability to support the development of disease pathogens. The integration of this new method within national vector control programmes is indeed the biggest challenge, notwithstanding the current weak health systems in most disease-endemic countries (DECs) to efficiently apply vector control interventions. Moreover, where integration is considered, it is essential that reliable data are available on the multiple effects of the interventions. This should be done in parallel to the general strengthening of both human, technical, financial and physical resources at all levels of the national health system.

F1000Research, 2016

After a 40-year hiatus, the International Congress of Entomology (ICE 2016) convened in Orlando, Florida (September 25-30, 2016). One of the symposia at ICE 2016, the Zika Symposium, covered multiple aspects of the Zika epidemic, including epidemiology, sexual transmission, genetic tools for reducing transmission, and particularly vector competence. While there was a consensus among participants that the yellow fever mosquito, Aedes aegypti, is a vector of the Zika virus, there is growing evidence indicating that the range of mosquito vectors might be wider than anticipated. In particular, three independent groups from Canada, China, and Brazil presented and discussed laboratory and field data strongly suggesting that the southern house mosquito, Culex quinquefasciatus, also known as the common mosquito, is highly likely to be a vector in certain environments.

Mosquito-borne diseases represent a significant global disease burden, and recent outbreaks of such diseases have led to calls to reduce mosquito populations. Furthermore, advances in ‘gene-drive’ technology have raised the prospect of eradicating certain species of mosquito via genetic modification. This technology has attracted a great deal of media attention, and the idea of using gene-drive technology to eradicate mosquitoes has been met with criticism in the public domain. In this paper, I shall dispel two moral objections that have been raised in the public domain against the use of gene-drive technologies to eradicate mosquitoes. The first objection invokes the concept of the ‘sanctity of life’ in order to claim that we should not drive an animal to extinction. In response, I follow Peter Singer in raising doubts about general appeals to the sanctity of life, and argue that neither individual mosquitoes nor mosquitoes species considered holistically are appropriately described as bearing a significant degree of moral status. The second objection claims that seeking to eradicate mosquitoes amounts to displaying unacceptable degrees of hubris. Although I argue that this objection also fails, I conclude by claiming that it raises the important point that we need to acquire more empirical data about, inter alia, the likely effects of mosquito eradication on the ecosystem, and the likelihood of gene-drive technology successfully eradicating the intended mosquito species, in order to adequately inform our moral analysis of gene-drive technologies in this context.

Vector-Borne and Zoonotic Diseases, 2008

This represents a collective effort of the Working Group members, and the views of all individual members could not be fully represented in this consensus document. Recognizing that the issues addressed herein are complex, and that there are many possible genetic engineering approaches that might be covered by this guidance, it is understood that specific issues will need to be addressed further when field containment plans are developed. The WG members all agree that this document provides useful guidance that should play a primary role in the development of project plans.

Frontiers in Environmental Science, 2023

Gene drives are genetic elements that in sexually reproducing organisms spread faster than those transmitted through a Mendelian fashion. Since gene drives can be engineered to modify different aspects of physiology and reproduction, they have been proposed as a new and revolutionary tool to control vector-borne diseases, particularly those transmitted by the genera Anopheles and Aedes (Culicidae), such as malaria, Dengue and Zika virus. This approach may impact on human health by lowering the transmission of such devastating diseases. However, the release of genetically modified mosquitos (or other species) into the environment raises a series of questions related to the still incipient technology and our present understanding of the complex structure and dynamics of terrestrial and aquatic ecosystems. Moreover, there are ethical concerns about human interventions in natural ecosystems that may eventually impact our way of living or the ecosystems themselves. This work is an interdisciplinary approach that analyzes from a biological, philosophical, and theological perspective the potential ecological impacts on natural environments of the release of genetically modified species, focusing on gene drive-modified mosquitos. It includes theological approach from a Catholic point of view (although it could be easily shared by other Christians) because we hold that world religions give valuable insights even though not everyone may share their groundings. We conclude that the focal problem is the relationship between humans and nature, and the release of genetically modified species may change this relationship unpredictably. However, given the complex interactions in ecosystems, new approaches such as Earth Stewardship principles could provide new and more widely accepted answers involving biological, philosophical, and theological concepts that will help engaging all relevant actors to make a better world

2020

One of the biggest challenges currently for public health in Brazil and worldwide are vector-borne diseases