A fungus that has been genetically modified (GM) to produce spider toxin can rapidly kill 99% of mosquitoes that carry and spread malaria. Following trials of the fungus – known as Metarhizium pingshaense – in Burkina Faso, 99% of malaria mosquito populations were wiped out in just 45 days. Metarhizium pingshaense was used because it naturally infects Anopheles mosquitoes (the ones that carry and spread malaria). Scientists then enhanced it using genetic engineering so the fungus would start creating its own version of a venom found in a species of funnel-web spider. For the trials, scientists built a fully-enclosed ‘mosquitosphere’ that mimicked a small village community. They introduced 1,500 mosquitoes. When the insects were left alone, their numbers soared, but when the fungus was introduced, just 13 mosquitoes remained after 45 days. The researchers say their aim is not to destroy all mosquitoes, simply to cull the spread of malaria – a disease that kills more than 400,000 people every year (mostly children). Speaking about the trials, Dr Tony Nolan, from the Liverpool School of Tropical Medicine, said: “These results are encouraging. “We need new and complementary tools to augment existing control methods, which are being affected by the development of insecticide-resistance.” The results of the GM fungus trials are published in the journal Science.