New World Screwworm Detected in Texas for First Time in 60 Years

New World screwworm has been confirmed in Texas for the first time in 60 years, according to reports from Rock Creek Ranch. The case was identified in a three-day-old calf in La Pryor and officially confirmed on June 3 by the U.S. Department of Agriculture’s National Veterinary Services Laboratories in Ames, Iowa.

How was the New World screwworm detected in Texas?

Robbie Graff, a ranch manager at Rock Creek Ranch in La Pryor, and his crew discovered the infestation during a routine check of water pivots and mineral distribution. Graff reported that a three-day-old calf exhibited a swollen naval area with blood around it.

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Graff contained the animal, removed the larvae, and treated the calf. He then contacted his veterinarian to submit samples for official testing, which led to the June 3 confirmation from the USDA in Iowa.

Did You Know? Robbie Graff recalls watching sterile flies being distributed from planes and trucks during his childhood, a strategy used to combat the pest 60 years ago.

What is the response to the screwworm outbreak?

Following the detection, Graff contacted the Texas Animal Health Commission and his veterinarian to follow established protocols. This report triggered the immediate deployment of sterile flies in the affected area.

Graff stated that officials began dropping flies the day after the case was reported. Since that intervention, no further cases have been detected on the ranch, and the affected calf recovered quickly.

Expert Insight: Samantha Carter notes that the speed of reporting is the primary factor in containment. Because the New World screwworm is a pest that targets wounds rather than a contagious disease, immediate identification and the use of sterile fly technology may prevent a localized case from becoming a widespread regional crisis.

Why does this detection matter for other ranchers?

Graff emphasized that New World screwworm is a pest infestation and not an infectious disease. According to Graff, the fly attacks existing wounds and is not transmitted from one animal to another or through the food chain.

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To prevent further spread, Graff and his crew have increased monitoring, checking cattle every day or every other day. He advised other ranchers to remain vigilant and report any suspected cases immediately to ensure rapid response.

What may happen next for South Texas herds?

The reemergence of the pest could lead to increased surveillance across South Texas ranches. If more cases are detected, officials may expand the distribution of sterile flies to other areas.

Ranchers may need to adopt more rigorous daily inspection routines to identify wounded livestock, as the pest’s northward movement continues to be a concern for the region.

Frequently Asked Questions

Is the New World screwworm a contagious disease?
No. According to Robbie Graff, it is a pest that attacks wounds and is not transmitted between animals or through the food chain.

Where was the Texas case officially confirmed?
The case was confirmed on June 3 by the U.S. Department of Agriculture’s National Veterinary Services Laboratories in Ames, Iowa.

What method is being used to eliminate the infestation?
Authorities are dropping sterile flies in the affected area, a strategy Graff notes was successful 60 years ago.

Do you believe increased daily livestock monitoring is sufficient to stop the spread of agricultural pests?