Millions of genetically modified mosquitoes crafted by UK-based biotechnology company Oxitec are to be unleashed across the United States to wipe out malaria with “death sex,” according to The Sun.
Messing with the sex life of mosquitoes
The reproduction patterns of mosquitoes begin like this: The female mosquito enters the swarm. The male will seek her based on the frequency of her wing beat, which is lower than the males’ frequency until his wings beat slowly to match the female mosquito. In less than a second, the two are joined, fly slowly out of the swarm, and then mate midair, although it can sometimes occur on a surface. Mating in mosquitoes is quick, usually lasting no more than 15 seconds. Understanding that 15-second frenzy and making sure that it will not lead to breeding has always been a challenge in research laboratories.
So, Oxitec’s scheme has been approved by the US Environmental Protection Agency. The mutant male mosquitoes that are to be released in the wild are genetically modified to kill off or lessen the number of mosquitoes in the country. Once released, they will mate with the wild females and their female offspring will die. Since only female mosquitoes bite because she needs blood to produce eggs, Oxitec’s insects will not spread the disease to people.
Oxitec received the experimental use permit on May 1 to release the modified mosquitoes they called OX5034. The mosquitoes will be released every week over the next two years in Texas and Florida.
Concern on the deployment of mosquitoes
A group of bioethicists, scientists, vector biologists, policy experts, and geneticists highlighted that such a strategy holds considerable potential benefits for hundreds of millions of people that are affected by mosquito-borne diseases every year. However, they also raised their concern that the scientific evaluation of gene-edited mosquitoes does not ensure responsible deployment.
Large-scale, repeated releases of genetically modified insects over time could lead to the temporary collapse of the wild populations and could halve the spread of diseases carried by mosquitoes.
Small mosquito bites, big consequences
Scientific online publication Our World in Data shares that global malaria deaths by world region have declined. In 2015, Africa held 9 out of ten malaria victims or 395,000 malaria deaths compared to other regions. Western Pacific had 3,200 malaria deaths, Eastern Mediterranean 7,300, South-East Asia 32,000, Americas 500, and Europe 0.
At a global level, the most vulnerable age group to malaria deaths are kids below five years old, which accounted for 57% of total deaths in 2017. The number of deaths from malaria decreased with age, with those over 70 years comprise around 5% of global deaths from malaria.
Mosquito-borne illnesses, including malaria, have been on the rise in the southern United States. The Sun added that this is due to climate change, increased the mosquito population in South America. Scientists have, however, raised their concern about the lack of oversight for the deployment of genetically modified mosquitos in Texas and Florida.
A call for precautionary oversight
The same project launched in Brazil backfired after the country released millions of genetically-hacked bugs into the neighborhoods of Jacobina. Other scientists believe that it accidentally created a super-resistant mosquito species that were even tougher to kill than before.
A charity dedicated to protecting the environment Friends of the Earth has likewise criticized Oxitec’s work. In 2012, Eric Hoffman from the said charity said that trials of mosquitoes should not push through in the absence of impartial and comprehensive reviews of the ethical, human health, and environmental risks.
In a press release, though, Oxitec said that field tests will be conducted. If these are approved by the local and state authorities, then the project will begin in summer 2020 in Florida and 2021 in Texas. As part of their field tests, the company will release into the environment male mosquitoes that carry a protein that will inhibit the survival of the female offspring. The male offspring will survive and become fully functional adults with the same genetic modification, they added. EPA also anticipates that the project will combat the spread of the Zika virus.
Oxitec will also be sampling and monitoring the mosquito population every week in selected areas in the US to determine how well the project works for mosquito control. This will also confirm if GM mosquito traits will disappear in the male mosquito population over time. EPA maintains the right to cancel the experimental use permit (EUP) during the 24 months if unforeseen outcomes will happen.
Unlike Oxitec’s approach, the International Atomic Energy Agency previously mentioned the use of the Sterile Insect Technique (SIT). It involves sterilizing the male insects through radiation in laboratories and then releasing them in the wild. This method has been proven effective in controlling the screwworm and fruit fly that attacks the livestock and crops, respectively. Entomologist Andrew Parker said via German news publisher DW that if they can reach local eradication of the pest species, then there’s no need for the use of pesticides. The scientists from the IAEA Seibersdorf laboratories believe that the SIT is effective pest control.
Genetic engineering in the natural world
Aside from mosquitoes that can’t spread malaria to humans, other projects show how genetic engineering has been changing the natural world. Another example would be the genetically modified coral reefs that can cope with the rising sea temperatures.
Coral geneticist Madeleine van Oppen can hear the clock ticking for coral reefs. In a study, which appeared in the American Association for the Advancement of Science, Van Oppen and colleagues re-engineered corals with techniques as new as the latest gene-editing tools and as old as the domestication of plants.
Genetic engineering has indeed offered humankind the unprecedented opportunity to reshape the structures of the biological world and is an important tool to alleviate global health burdens. However, it’s not easy to assess the final risk determination. Shortcomings in the release of millions of GM mosquitoes should be addressed.