学物理一定要上985吗? | 8k8 com. | Updated: 2024-08-17 10:41:23
The World Health Organization announced this year that China has become a certified malaria-free country. For a nation with a population the size of China's, this is a unique scientific achievement. Not a single case of the disease or domestic transmission has been reported for several years, a notable public health achievement for any country battling such a deadly disease.
Soon, new genetic engineering breakthroughs from the United Kingdom may make it possible to render female mosquitoes infertile, essentially crashing their populations in the wild.
This means that as tough a year as 2021 as has been for many people internationally, it may yet signal the beginning of the end to one of the world's deadliest diseases.
The concept of releasing genetically-altered mosquitoes has been of interest to scientists for some time. In May this year, a population of engineered mosquitos was released in Florida as a testing method to suppress populations that have the potential to carry a wide range of diseases. Mosquitos do not just carry malaria; other infections such as Zika, yellow fever and dengue are all carried on vectors which, until now, scientists had little hope of controlling.
In Florida, genetically-engineered males that do not bite humans anyway have been introduced to wild populations where they then mate with local females. These males carry a gene which results in the death of females in their early larval stages. This means that overtime the female population becomes lower and lower, resulting in a dwindling population.
The concept is simple in nature and the method can take many forms. Other similar methods under development in parts of Africa such as Burkina Faso tweak the formula slightly, rendering females infertile instead of destroying them early on, but the premise of self-destructing mosquito populations is a promising one.
China has been at the forefront of this work, part of an aggressive innovative research response to malaria which resulted in the country achieving malaria-free status earlier this year.
Two years ago, Chinese scientists managed in an experiment to wipe out an entire population of dangerous disease-carrying Asian tiger mosquitoes on two whole islands in southern China, genetically engineering the animals so that males in the population would become infertile over time. Over two years, a specially-bred swarm of 200 million was introduced, and crashed the indigenous population, resulting in a disease-free environment for residents.
The future of so-called gene drives that help control dangerous populations of pathogens or pests will play a vital role in the coming century. Gone will be the days of expensive and side effect-ridden malaria medications and insect safety nets. It is estimated that currently, each year nearly half a million people die from mosquito related-infections, meaning that rapid deployment of safe and effective solutions is critical.
The scope for such technology does not just lie with flying insects, however. Similar projects are underway for disease-carrying rats and other larger, more complex animals. Invasive species, such as rabbits and cane toads, have caused havoc to local ecosystems and can damage livelihoods, as well as threatening local species. Genetic engineering has also led to certain types of drug-resistant strains of bacteria and fungus being eradicated in experiments, raising hopes that instead of responding to infections, medicine may soon be in a position to proactively act first and limit the threats that problematic organisms can create.
For now, China's malaria-free status is a significant milestone in itself. Going from an estimated 30 million cases a year to zero has led to countless lives being saved through the country's proactive approach toward the disease.
If genetic engineering and gene driving technology is carefully regulated and valued to its full potential, countless other diseases that previously relied on uncontrollable natural vectors may be addressed.