Screwworm Appears in US Livestock for First Time Since 1966

(MENAFN) A flesh-eating parasite known as the screwworm has been detected in cattle in Texas, marking the first confirmed case in U.S. livestock since 1966, according to reports.

The U.S. Department of Agriculture said Wednesday that the presence of the New World screwworm (NWS) was confirmed in a bovine in Zavala County. The parasite had previously been considered eradicated in the United States for decades.

In a statement, the department warned that NWS poses a serious threat to animals and, in rare cases, humans.

“NWS is a serious pest that affects livestock, pets, wildlife, and less commonly, people and birds. NWS larvae (maggots) burrow into the flesh of living animals, causing serious damage to livestock and economic losses,” the department said.

Officials said larvae were discovered in the umbilical area of a 3-week-old calf. No additional cases have been identified so far.

In response, agricultural authorities have deployed response teams in Texas, establishing a restricted zone of about 20 kilometers (12.4 miles) around the detection site, along with quarantine measures, movement controls, and intensified surveillance.

Authorities are also expanding the use of sterile fly release programs, a biological control method designed to reduce reproduction of the pest and prevent its spread.

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