From Panama To The Plains: Screwworm Is On The Move - BGWT 113

The New World Screwworm, once thought gone from U.S. pastures, is creeping north again—and it’s bad news for both livestock producers and wildlife enthusiasts. 
In this episode of Blazin’ Grazin’ and Other Wild Things, Dr. Jonathan Cammack of OSU Extension walks listeners through the pest’s history, the landmark sterile fly eradication program, and the sobering reality that it’s now only 300 miles from the U.S. border. 
We explore how the insect’s gruesome feeding habits devastate livestock and deer populations, why winter weather offers only partial protection, and what producers can do to spot and treat infections early.

The conversation also highlights the equally concerning arrival of the Asian Longhorned Tick in northeast Oklahoma. 
This invasive parasite reproduces asexually, spreads rapidly, and carries livestock diseases already present in nearby states. 
Whether you’re managing a herd, tracking deer health, or just passionate about Great Plains wildlife, this episode delivers timely, practical insight into two pests that demand vigilance.

10 Key Takeaways

1. The New World Screwworm is advancing north from Central America into central Mexico.
2. Eradication in the U.S. was achieved through sterile fly releases starting in the 1950s.
3. Current spread appears to be aided by illegal or uninspected livestock movement.
4. Screwworm larvae feed on both dead and living tissue, causing severe wounds and death.
5. The pest threatens both livestock and wildlife, with deer being particularly vulnerable.
6. Cold winters can limit natural spread, but human-mediated jumps bypass that barrier.
7. Livestock owners should inspect animals weekly and treat all wounds promptly.
8. Few insecticides are approved for screwworm, and their effectiveness is short-lived.
9. The Asian Longhorned Tick is a newly detected invasive species in Oklahoma.
10. Cooperation between the U.S., Mexico, and Panama is key to keeping screwworm at bay.

Time Stamps

00:02:04 – Introduction of Dr. Jonathan Cammack and defining “New World” Screwworm
00:03:17 – Historical presence and eradication in the U.S.
00:05:14 – The sterile fly release program explained
00:08:47 – Early detection challenges and illegal livestock movement
00:10:42 – Life cycle of the screwworm and why it’s so destructive
00:13:41 – Efforts to reopen production and distribution facilities
00:14:50 – Wildlife impacts, with focus on deer mortality
00:18:47 – Challenges in controlling wildlife-borne spread
00:21:06 – Life span, temperature limits, and seasonal spread
00:22:18 – Livestock management practices to reduce risk
00:24:01 – Approved insecticides and treatment limitations
00:27:13 – Update on the Asian Longhorned Tick in Oklahoma
00:30:27 – Why the current screwworm spread is different from past outbreaks
00:31:59 – Resources for producers and wildlife managers

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