London: Bacteria in the gut of disease-bearing insects — including the mosquito which carries the Zika virus — can be used as a Trojan horse to help control the insects’ population, reveals a new research. “Our method could also help in the fight against the Zika virus, as the Aedes mosquito that bears the virus has bacteria that would be suitable,” said Paul Dyson, professor at Swansea University in Wales in Britain.
It can help us to tackle some of the insects and crop pests that have such a devastating impact on human health and the food chain, he added.
The research showed decline in fertility up to 100 percent and an increase of 60 percent in the mortality rate of larvae, amongst the insects studied. Researchers used a technique, known as symbiont-mediated RNAi, that uses friendly (symbiotic) bacteria to inhabit an insect’s gut as a Trojan horse to deliver a “switch off” command to chosen target insect genes.
“This technology allows us to target insects much more effectively than conventional pesticides, and without their side effects. Using bacteria as a Trojan horse gets round some of the problems in delivering RNAi to the insect,” Dyson noted. The study revealed that the RNAi can be targeted specifically at the species in question, and does not harm other insects, such as bees and other pollinators.
It also does not carry the risk of environmental damage and harm to human health and insects do not acquire resistance to it in the way that they do to chemical pesticides. The symbiotic bacteria are programmed to manufacture the RNAi molecules inside the insect’s body, for as long as needed, and they do this without being detected by the insect’s immune system. The bacteria are specific to that particular insect and cannot live outside it.
The study, published in the journal Proceedings of the Royal Society B, represents a significant advance in the ability to deliver RNAi, potentially to a large range of non-model insects, the researchers said adding that the technique would be transferable to many insect species, including the Aedes mosquitoes, which carry the Zika virus.