New Genetically Modified Fly About to be Released

December 15, 2016 – Oxitec, the UK company that has made its specialty modifying disease-spreading insects to limit the damage and death they cause, is about to tackle the Medfly problem. Not familiar with the Medfly? It’s in reference to the Mediterranean Fruit Fly, (Cerititis capitata), an insect whose larvae infest fruit and fruiting vegetables. According to the California Department of Food and Agriculture, the Medfly is “considered the most important agricultural pest in the world” infesting 300 fruit, nuts and vegetables “making them unfit for human consumption.” Damage to apples, apricots, avocados, bell peppers, figs, grapes, grapefruit, lemons, limes, melons, nectarines, oranges, peaches, pears, persimmons, plums, pomegranates, tangerines, tomatoes and walnuts are among the many that fall victim to this insect which is a native of Africa but has spread globally.

Eradication programs range from application of chemical pesticides to the introduction of sterilized irradiated insect pupae (a larval stage before the adult fly emerges) to interfere with reproduction. In California fly release for eradication is done over two life cycles and success is determined when no adult flies are found eight months after application. Medfly outbreaks are estimated to have cost California $500 million (US) over the past 25 years. And the only way to conceivably block outbreaks in California has been to impose trade embargoes from countries of origin which amounts to 43 at present with 500 unique localities. It is expected that climate change will further enable Medfly spread. So a genetically modified Medfly may be just the ticket to control outbreaks.

What Oxitec has developed is a “self-limiting” Medfly. It mates with wild Meflies to suppress the insect population. In controlled netted releases done in Western Australia, compared to the sterilized irradiated technology, the Oxitec Medfly produced better results. Tests done in glassed-in greenhouses in Crete eliminated the insect pests withint 12 Netted trials in Morocco produced similar results. Now Oxitec is ready to do open field trials noting that their “self-limiting” Medfly can save agribusiness billions of dollars annually.

I have written about Oxitec before, a company spun out from Oxford University’s research laboratories focused on developing genetically modified insect technology. The company has developed “self-limiting” Aedes aegypti, the mosquito responsible for the spread of dengue, malaria and the Zika virus.