US containment efforts slow northward spread of New World screwworm with new sterile-fly facility

US officials report a decline in New World screwworm cases in south Texas as enhanced surveillance and a new sterile-fly facility bolster efforts to halt the parasite’s spread across North America.

A senior US agriculture official said the northward movement of New World screwworm in south Texas is easing, as federal efforts to contain the parasite intensify and a new sterile-fly facility is brought forward.

Rear Admiral Michael Schmoyer, the US Department of Agriculture’s lead screwworm coordinator, said public data showed 45 confirmed US cases, but only three remained active. He said the recent rise in detections was consistent with the early phase of an outbreak and that wider surveillance, public reporting and targeted sterile-fly releases were now helping to slow spread.

The CDC says the parasite has re-emerged across Central America, Mexico and the southern US, with the first US detection identified in a calf in Zavala County, Texas. No locally acquired human infestations have been recorded.

Schmoyer said wildlife remains the weakest point in the defence line because it is harder to regulate than livestock movement. He added that most cases arise when infested animals are transported, rather than from wild flies travelling long distances.

USDA and the Army Corps of Engineers have begun work on a sterile-fly production site at Moore Air Base in Edinburg, Texas. The facility is intended to ramp up domestic capacity, with industry groups saying it could eventually produce 100 million sterile flies a week.

Source: Noah Wire Services