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For the first time in 60 years, a case of New World screwworm has been found on American soil. A calf in Texas was infected with a flesh-eating fly larva. NPR's Pien Huang reports on the bug that poses a major threat to the cattle industry.
PIEN HUANG, BYLINE: To the U.S. Department of Agriculture, the discovery of a single screwworm case is like an emergency. Here's Secretary Brooke Rollins in a media call.
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BROOKE ROLLINS: We have a unified incident command team. We've established a 20-kilometer control area - a zone around the detection.
HUANG: Within hours of hearing about the suspected case, the USDA sent a team of responders to Texas. Officials had been alert to the possibility for several years as reports of the screwworm fly moved up from the South American continent.
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ROLLINS: The fly doesn't fly itself - or, I should say, herself - long distances.
HUANG: Rollins says the fly and larvae move with the cattle trade.
ROLLINS: And that's how it's moved from South America, Central America, into Mexico and how it eventually got to America.
HUANG: The fly lays eggs in open wounds, which hatch into flesh-eating larvae. Bud Dinges with the Texas Animal Health Commission says the calf was found at a South Texas ranch in Zavala County, about 60 miles from the U.S.-Mexico border.
BUD DINGES: We had a 3-week-old beef calf that had a umbilical lesion and had larvae in the umbilical lesion itself there.
HUANG: The discovery set off big alarm bells among cattle ranchers. If it spreads widely, it could be devastating to the cattle industry, according to a joint report from Texas A&M and the USDA last year. Rear Admiral Michael Schmoyer with USDA is leading the agency's efforts against the screwworm.
MICHAEL SCHMOYER: And so I do want to emphasize that there is only one infested animal. It is that 3-week-old beef calf. It is not a danger to the food supply.
HUANG: The screwworm larva only eats living flesh, including that of livestock, wild animals and pets and, in rare cases, humans. In the early 1900s, the New World screwworm was a scourge on the cattle industry until it was eradicated in the 1960s by the release of many, many sterile flies. They mate but don't have babies, so the population goes down. Schmoyer says that's the main strategy today - releasing more sterile flies.
SCHMOYER: Two million flies are dispersed. That'll be done twice a week for a total of 4 million flies a week.
HUANG: USDA officials are also asking ranchers to be vigilant and check their cattle. The U.S. is planning to open a new sterile fly factory in Texas next year.
Pien Huang, NPR News.
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