Success from the past
As the host and the geographical reach of the flies expand, the pressure becomes intensifying to arrange the flies – something that many countries have been able to do in the past.
Decades ago, screwworms were endemic in Central America and the South. However, governments in the regions used intensive, coordinated control efforts to push the flies to the south. Screwworms were eliminated from the US around 1966 and were pushed down by Mexico in the 1970s and eighties. They were eventually voted eliminated from Panama in 2006, with the population kept at a distance by a biological barrier at the Darénen Gap, on the border of Panama and Colombia. In 2022, however, the barrier was violated and the flies began to go north, mainly due to non -monitoring cattle movements. The last surveillance suggests that the flies are now about 370 miles south of Texas.
The most important method to wipe out screw worms is the sterile insect technology (SIT), which operates a weakness in the life cycle of the fly, because they tend to mate only once. In the 1950s, researchers from the US Department of Agriculture found out that they could use Gamma radiation to sterilize male flies without influencing their ability to find partners. They then breeding huge amounts of male flies, sterilized and carpet bombed bombed areas with air issue, which refueled the population.
Panama, in collaboration with the US, maintained the biological barrier on the Colombian border with continuous sterile-fly bomb attacks for years. But when De Vliegen approached this year, the USDA moved its air deliveries to Mexico. In June, the USDA announced plans to set up a new sterile flight facility in Texas for deliveries in the air to Noord -Mexico. And last month the USDA cattle trade from southern access points stopped.
Miller said today in the announcement that SIT is no longer enough, and Texas is taking his own steps. These include the new AAS, insecticides and new food for cattle and deer peppered with the anti-parasitic drug ivermectin. Miller also said that the state wants to develop a vaccine for cattle that could kill larvae, but such a shot is still under development.
