News

04/06/2019

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.

02/08/2018

Dengue fever is a mosquito-borne viral disease found in tropical and sub-tropical climates worldwide. Severe dengue is a leading cause of death and serious illness among children in Asian and South American countries. Unfortunately, there is no definitive medical treatment for dengue fever, but hope may be on the horizon. That’s because researchers in Australia say they have managed to eradicate dengue from an entire city using captive-bred mosquitoes. The captive-bred mosquitoes have the naturally-occurring bacteria Wolbachia, which hinders dengue transmission. The bacteria are spread as the released mosquitoes mate with local mosquitoes. As a result, the city of Townsville has been dengue-free since 2014. The researchers, all of whom are from Monash University, also believe the technique could be used to stop other mosquito-borne diseases like Zika and malaria. Speaking to the Guardian, Scott O'Neill, director of the World Mosquito Program, said: "Nothing we've got is slowing these diseases down - they are getting worse." "I think we've got something here that's going to have a significant impact and I think this study is the first indication that it's looking very promising." The results of the Australian researchers’ study were published in Gates Open Research. The next step is to trial the approach in Yogyakarta in Indonesia - a city of nearly 390,000.

07/09/2017

The harmful Zika virus, which is spread by mosquitoes and causes devastating brain damage in babies, could be used to treat aggressive brain cancer in adults, according to US scientists. Up until now, Zika has only been seen as a major global health threat, but the new research could see it become a remedy. The scientists say the virus can be used to selectively infect and destroy hard-to-treat cancerous cells in adult brains. In mice studies, the Zika virus was seen to successfully shrink aggressive tumours, yet left other brain cells unscathed. While human trials are still quite a way off, laboratory tests show that the virus works on human cells, and experts believe the Zika virus holds a huge amount of potential. They say it could be injected into a human brain at the same time as surgery to remove life-threatening tumours. Some brain cancers are fast growing and spread quickly through the brain. This makes it very difficult to see where the tumour finishes and healthy tissue begins. As an extra precaution, the team from Washington University School of Medicine and the University of California San Diego School of Medicine have already begun modifying the Zika virus to make it less potent than the regular strain. Researcher Dr Michael Diamond said: "It looks like there's a silver lining to Zika. This virus that targets cells that are very important for brain growth in babies, we could use that now to target growing tumours."

06/07/2017

A team of researchers have successfully culled mosquito populations in nine West African villages by cutting off their food supply, reducing the risk of malaria in those areas. By removing flowers from a common plant that has become a horticultural bully – the Prosopis juliflora shrub – the researchers were able to kill off lots of the older, adult, female, biting insects that transmit malaria. Experts believe that by reducing the amount of nectar (energy) available to these older “granny” mosquitoes, the cycle of malaria transmission can be stopped. That’s because it’s only these Anopheles mosquitoes that carry the malaria parasite in their saliva and transmit it to people when they bite and draw blood. An infected person can then pass the parasite on to other younger, biting, female mosquitoes, increasing the spread of the parasites further. In the villages where the flowers of the Prosopis juliflora shrub were removed, mosquito numbers were seen to drop by almost 60%. While there is no direct proof, the researchers believe the mosquitoes died of starvation. Reporting the team’s findings in the journal Malaria Research, Prof Jo Lines, a malaria control expert from the London School of Hygiene and Tropical Medicine, said the novel approach held amazing potential, alongside other malaria prevention strategies.