# Valley ranchers concerned over screwworm threat following outbreak in southern Mexico

> A South Texas ranch and a regional rancher warn that the New World screwworm, a fly that burrows into open wounds of warm-blooded animals, is spreading north through Mexico. Representative Monica De La Cruz proposed legislation asking the USDA to study the threat and prepare a response. Local ranchers are deworming herds and are most worried about calf losses if the pest crosses the border.

- Date: 2026-11-02 · published 2026-11-02T09:14:20.880Z
- Category: disease · region US · magnitude medium
- Page: https://feedsoft.ai/events/75305-valley-ranchers-concerned-over-screwworm-threat-following-outbreak-in-southern
- Commodities: [Live Cattle](https://feedsoft.ai/c/LCATTLE.md), [Feeder Cattle](https://feedsoft.ai/c/FCATTLE.md)

## Why it matters

A screwworm incursion into US cattle country would threaten calf crops and herd health, tightening the already tight feeder and live cattle supply. Continued border restrictions on Mexican cattle would also keep supply constrained, which supports cattle prices.

## Read by commodity

- FCATTLE: bullish ▲
- LCATTLE: bullish ▲

## Similar past events

| Commodity | Date | Event | 5-day % | 20-day % |
| --- | --- | --- | --- | --- |
| LCATTLE | 2026-07-19 | [What the U.S. can learn from Mexico's handling of the screwworm outbreak - VPM](https://feedsoft.ai/events/18298-what-the-u-s-can-learn-from-mexico-s-handling-of-the-screwworm-outbreak-vpm.md) | -1.4% | -2.8% |
| LCATTLE | 2026-08-22 | [US-Mexico: Screwworm is squeezing ranchers on both sides of the border \| CNN](https://feedsoft.ai/events/17847-us-mexico-screwworm-is-squeezing-ranchers-on-both-sides-of-the-border-cnn.md) | -1.6% | -2.8% |
| LCATTLE | 2025-05-13 | [Mexico to tighten cattle flows from south, rules out shutting border over screwworm](https://feedsoft.ai/events/24641-mexico-to-tighten-cattle-flows-from-south-rules-out-shutting-border-over.md) | -0.5% | +5.0% |
| LCATTLE | 2024-05-09 | [Nicaragua reports screwworm outbreak in cattle
						 \| The Cattle Site](https://feedsoft.ai/events/30190-nicaragua-reports-screwworm-outbreak-in-cattle-the-cattle-site.md) | +0.6% | +2.4% |
| LCATTLE | 2025-07-10 | [US again halts cattle imports from Mexico over flesh-eating screwworms \| Reuters](https://feedsoft.ai/events/23700-us-again-halts-cattle-imports-from-mexico-over-flesh-eating-screwworms-reuters.md) | +2.6% | +6.8% |
| FCATTLE | 2026-07-19 | [What the U.S. can learn from Mexico's handling of the screwworm outbreak - VPM](https://feedsoft.ai/events/18298-what-the-u-s-can-learn-from-mexico-s-handling-of-the-screwworm-outbreak-vpm.md) | -0.2% | -1.5% |
| FCATTLE | 2025-05-13 | [Mexico to tighten cattle flows from south, rules out shutting border over screwworm](https://feedsoft.ai/events/24641-mexico-to-tighten-cattle-flows-from-south-rules-out-shutting-border-over.md) | -2.4% | +3.3% |
| FCATTLE | 2025-07-10 | [US again halts cattle imports from Mexico over flesh-eating screwworms \| Reuters](https://feedsoft.ai/events/23700-us-again-halts-cattle-imports-from-mexico-over-flesh-eating-screwworms-reuters.md) | +1.6% | +7.7% |

## Sources

- krgv.com: https://www.krgv.com/videos/valley-ranchers-concerned-over-screwworm-threat-following-sightings-in-southern-mexico/

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