# Nuevo Leon cow tests positive for screwworm, Texas ranchers urged to monitor herds

> A cow in Nuevo León, Mexico, tested positive for New World screwworm about 60 miles from the Texas border, according to a Texas Agriculture Commissioner news release. Texas ranchers were urged to monitor herds, and USDA sterile fly releases are ongoing from a facility near Edinburg.

- Date: 2026-10-31 · published 2026-11-01T06:16:00.045Z
- Category: disease · region US · magnitude low
- Page: https://feedsoft.ai/events/4561-nuevo-leon-cow-tests-positive-for-screwworm-texas-ranchers-urged-to-monitor
- Commodities: [Live Cattle](https://feedsoft.ai/c/LCATTLE.md), [Feeder Cattle](https://feedsoft.ai/c/FCATTLE.md)

## Why it matters

A closer case increases outbreak risk for Texas herds, which could later reduce cattle supplies and support prices if it spreads into the U.S.

## Read by commodity

- FCATTLE: bullish ▲
- LCATTLE: bullish ▲

## Similar past events

| Commodity | Date | Event | 5-day % | 20-day % |
| --- | --- | --- | --- | --- |
| LCATTLE | 2025-08-15 | [In Texas cattle country, ranchers brace for flesh-eating screwworms \| Reuters](https://feedsoft.ai/events/23280-in-texas-cattle-country-ranchers-brace-for-flesh-eating-screwworms-reuters.md) | +1.1% | -0.1% |
| LCATTLE | 2023-10-22 | [A screwworm fly that bedeviled cattle ranchers decades ago has returned to Texas](https://feedsoft.ai/events/33562-a-screwworm-fly-that-bedeviled-cattle-ranchers-decades-ago-has-returned-to-texas.md) | +0.4% | -3.5% |
| LCATTLE | 2026-06-04 | [Texas Ranchers Brace as New World Screwworm Returns to US Soil After 6 Decades](https://feedsoft.ai/events/12087-texas-ranchers-brace-as-new-world-screwworm-returns-to-us-soil-after-6-decades.md) | +0.6% | -1.0% |
| LCATTLE | 2023-10-23 | [Mexico boosts controls on cattle after new screwworm case found near US border in Nuevo Leon](https://feedsoft.ai/events/33561-mexico-boosts-controls-on-cattle-after-new-screwworm-case-found-near-us-border.md) | +0.4% | -3.5% |
| LCATTLE | 2026-05-20 | [Ranchers herd it all as fewer cattle pressure beef prices; screwworm lurks - Dallasfed.org](https://feedsoft.ai/events/19198-ranchers-herd-it-all-as-fewer-cattle-pressure-beef-prices-screwworm-lurks.md) | -1.7% | -1.2% |
| FCATTLE | 2023-10-22 | [A screwworm fly that bedeviled cattle ranchers decades ago has returned to Texas](https://feedsoft.ai/events/33562-a-screwworm-fly-that-bedeviled-cattle-ranchers-decades-ago-has-returned-to-texas.md) | -2.0% | -5.5% |
| FCATTLE | 2026-06-04 | [Texas Ranchers Brace as New World Screwworm Returns to US Soil After 6 Decades](https://feedsoft.ai/events/12087-texas-ranchers-brace-as-new-world-screwworm-returns-to-us-soil-after-6-decades.md) | +3.4% | +5.3% |
| FCATTLE | 2023-10-23 | [Mexico boosts controls on cattle after new screwworm case found near US border in Nuevo Leon](https://feedsoft.ai/events/33561-mexico-boosts-controls-on-cattle-after-new-screwworm-case-found-near-us-border.md) | -2.0% | -5.5% |

## Sources

- krgv.com: https://www.krgv.com/videos/nuevo-leon-cow-tests-positive-for-screwworm-texas-ranchers-urged-to-monitor-herds/

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Data from Feedsoft AI (https://feedsoft.ai/). For information only; not investment advice.