Return of New World Screwworm Raises Concerns for US Livestock and Human Health
Return Of The Screwworm: Can The Flesh-Eating Parasite Found In US Cattle Infect Humans?

Image: News 18
The New World screwworm, a flesh-eating parasite, has re-emerged in La Pryor, Texas, marking the first case since 1966. While the immediate threat to human health is low, the parasite poses significant risks to livestock, potentially impacting the $113 billion US cattle industry. Quarantine measures and sterile fly releases are being implemented to contain its spread.
- 01The New World screwworm was confirmed in a 3-week-old calf in La Pryor, Texas, the first case in the state since 1966.
- 02Texas, the leading cattle-producing state, has a cattle industry valued at approximately $17 billion.
- 03The USDA has initiated a response involving quarantines, surveillance, and an expanded sterile fly release program to combat the infestation.
- 04Human infections are rare but can occur, particularly among those working with livestock; the last US case was reported in August 2023.
- 05The screwworm can cause severe damage to livestock, feeding on live tissue and potentially leading to death if untreated.
Advertisement
In-Article Ad
The New World screwworm, a parasitic fly known for infesting warm-blooded animals, has been confirmed in La Pryor, Texas, marking the first occurrence in the state since 1966. The US Department of Agriculture (USDA) reported this case in a 3-week-old calf, raising alarms in a region critical to the US cattle industry, valued at about $113 billion. The parasite poses a serious threat to livestock, as its larvae feed on live flesh, potentially leading to severe infections and even death. In response, the USDA has implemented quarantine measures, movement restrictions, and an expanded sterile fly release program, which involves releasing millions of sterilized flies to reduce the population of the screwworm. Although the risk to human health is currently considered low, there have been rare cases of human infection, notably a travel-related case in Maryland in August 2023. The return of this parasite underscores the importance of vigilance in livestock management and public health.
Advertisement
In-Article Ad
The re-emergence of the New World screwworm poses a significant threat to livestock health and could disrupt the cattle industry in Texas, affecting local economies.
Advertisement
In-Article Ad
Reader Poll
What do you think is the biggest threat posed by the return of the New World screwworm?
Connecting to poll...
More about US Department of Agriculture

US Launches Plan to Combat Flesh-Eating Screwworm Outbreak Using Sterile Flies and Detection Dogs
The Bbc • Jun 5, 2026
New World Screwworm Detected in Texas Calf, USDA Implements Quarantine Measures
Jpost • Jun 4, 2026

USDA Investigates Possible New World Screwworm Case in South Texas
Hindustan Times • Jun 4, 2026
Read the original article
Visit the source for the complete story.





