Beef Prices Are Already Sky High. Now Comes Screwworm.

Summary

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Episode Overview

Theme:
This episode of The Bulwark's "Bulwark Takes" is hosted by Kathryn Rampell, with guest Jonathan Cohn, delving into the reappearance of the New World screwworm in the United States. The discussion blends wit and precision as it explores the biology of the parasite, the potential economic and agricultural impacts, blame-shifting across political lines, and the effectiveness of containment policies—against a backdrop of already sky-high beef prices.

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Key Discussion Points and Insights

1. What is the New World Screwworm?

[00:00–02:32]

• Biology and Threat:

  • The New World screwworm is not a worm but a parasitic fly. The female lays eggs in wounds (primarily on mammals), and the larvae consume living flesh, potentially causing severe infections or death if untreated.
    • Jonathan Cohn: “They’re literally eating flesh... you can get secondary infections, and in mammals, it can eventually become deadly, if not from the larvae, then from the secondary infection itself.” (01:42)
  • Historically, it had been eradicated from U.S. livestock since 1966. Human cases are rare but possible and treatable, notably with ivermectin.

• Notable Moment:

  • Kathryn Rampell: “So not something you and I want to get.” (01:50)
  • Jonathan Cohn: “No cattle, no, nothing we want to get.” (01:55)

2. How Did the Screwworm Return?

[02:32–05:34]

• Previous Eradication:
  • In the 1960s, the screwworm was eradicated by flooding populations with irradiated sterile males—a technique still used today.
  • Barrier zones, including the Darien Gap, prevented the northward migration from South America.
• Recent Re-emergence:
  • The parasite has slowly moved northward in the last 2–4 years, with recent cases in deer populations in Florida.
  • Possible causes include:
    • Disruptions during COVID (supply chain, travel, and maintenance of control measures).
    • Ecological and cattle population shifts.
    • No conclusive single cause, but migration predates recent border policy debates.
  • Jonathan Cohn: “There's a couple of theories... Looks like it's a combination of factors. Some related to cattle populations, some related to weather change—there’s a whole bunch of different factors going on.” (04:13)

3. The Politics of Blame: Immigration Policy and Screwworm

[05:34–08:05]

• Blame on Biden and “Open Borders”:
  • Trump administration figures, including USDA Secretary Brooke Rollins, blamed Biden’s border and immigration policies for the breach.
    • Citing a tweet: “It was the direct result of the Biden Harris administration’s weak foreign policy agenda and failed immigration policies and wide open border...” (05:41)
• Debunking the Narrative:
  • Jonathan Cohn counters with evidence that the parasite’s movement predates the Biden administration’s immigration changes.
    • Jonathan Cohn: "Everything I've seen and read and what I've heard suggests that immigration really doesn't... That doesn't fit the timing... It's not likely that this migrated across the gap on humans." (06:59)
  • More plausible factors: COVID-era disruptions—not policy or border security failure.

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Notable Quotes and Memorable Moments

• On Screwworm’s Nature:

  • Jonathan Cohn: "They’re literally eating flesh..." (01:42)

• On Human Risk:

  • Kathryn Rampell: “So not something you and I want to get.” (01:50)
  • Jonathan Cohn: “No cattle, no, nothing we want to get.” (01:55)

• On Eradication Tactics:

  • Jonathan Cohn: "You breed sterile male flies... They mate with the females. Female screw flies only mate once... If they mate with the sterile male, they will not create offspring." (03:40)

• Skepticism About Border Blame:

  • Jonathan Cohn: “This is not about, this is not an immigration issue.” (08:00)

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Significant Timestamps

• 00:00–01:50: Introduction to screwworm, threat assessment, biology.
• 02:32–03:12: Human infection rarity; history of U.S. cases and treatments.
• 03:12–05:34: Historical eradication, barriers, recent outbreaks, migration theories.
• 05:34–08:05: Political finger-pointing—dissecting claims about immigration policy.

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Takeaways

• The New World screwworm’s return is a multifaceted agricultural concern, not a straightforward political issue.
• While rare in humans, the parasite poses significant risks for livestock—and by extension, for beef prices already under strain.
• The episode debunks political narratives that seek to tie the outbreak to recent immigration policy, pointing instead to complex ecological, logistical, and pandemic-related causes.
• A mix of expert commentary, historical context, and sharp humor provides listeners with both facts and perspective on an issue likely to dominate agricultural and political headlines.

Transcript

[A]

Hi everyone. I'm Kathryn Rampel, Economics editor at the Bulwark. Thanks so much for joining me. For Bulwark Takes, I am joined by my excellent colleague Jonathan Cohn to talk about the most comedic, most entertaining of topics. Flesh eating parasites. Jonathan, let's talk a little bit about the New World screwworm that has apparently now invaded the United States. This week, Agriculture Secretary Brooke Rollins announced a case of New World screwworm that was confirmed in a three week old calf in La Prior, which is near the US Mexico border. What is the screw worm? And should we be freaked out?

[B]

Yeah, well, we should be a little freaked out, especially if we care about, you know, the agriculture business. The New World screwworm, it is a fly actually. It's the New world screw worm fly. And basically the. Yeah, and the fly, the female fly, it, it finds open wounds in mammals. Other. I think it's just mammals. I. You know, but commonly livestock, for example, finds open wounds. It lays its eggs in the open wounds. The larvae grow, they kind of nodded, chew at the wound. That's where the flesh eating comes. They're literally eating flesh. Eventually, after a couple of days, they drop out. The larvae then burrow into the ground. They make new flies and that's how the whole cycle replicates. But meanwhile, during that period, while they are in the wounds and flesh, they are causing problems. You know, they're eating flesh. In addition to that, you can get secondary infections. And in mammals, um, you know, it can eventually become deadly, if not from the larvae, then from the secondary infection itself.

[A]

Okay, so not something you and I want to get. Not something we want.

[B]

No cattle, no, nothing we want to get.

[A]

We have a herd of cattle.

[B]

Yeah, yeah. I mean it mainly is, it's mainly an issue for, for livestock, for animals, for wild animals. It can infect humans. It's not common. Doesn't happen much, but it does happen. Um, we actually had a case a couple of years ago in Maryland. A woman who had come from somewhere in Central or South America, which is, it is endemic to the Americas, brought it up, got infected. Um, she wasn't. We were able to treat it. We can treat it and actually you can treat it with ivermectin. You know, the great medicine that was supposedly, was great for Covid. Yes.

[A]

Now really relevant again.

[B]

Yes, yes, yes. Well, you know, it's, it's, it's an anti parasite drug. So this is a parasite and this is, this is actually what it works for. So we can treat it in humans again, you know, on these sort of skin scale of Human pandemics that we need to worry about. We got Ebola running around in hantavirus, you know, you know, this is not that event. I mean, this is, I, I, I, I do not worry about, you know, human impact, but very big issue for animals and for livestock. Historically, it's been a big problem for ranchers. And, and it was, in fact, we eventually going way back in the 1960s, we finally figured out a way kind of eradicate it. And we did get rid of it here in the United States. But again, now we have a case here.

[A]

Yeah. So we haven't had it in livestock in the United States since I think I had read, like, 1966. Yeah. First confirmed detection of New world screw. Oh, at least in Texas, since 1966. So why is it back?

[B]

Yeah, so it is back. And this is a sort of, this is not entirely clear, but we had basically up, pushed it all the way down, kept it from coming north of South America. You there, you basically, the way you get rid of it, the eradication method, is you breed sterile male flies. You basically take the male version, you irradiate them so they become sterile, and then you release them into the wild. They mate with the females. Female screw flies only mate once during their lifetime. So if they mate with the sterile male, they will not create offspring. That's how you eradicate them. Turns out to be a remarkably effective way of getting rid of them. That's how we got rid of them in the 1960s. It is endemic, so it does keep popping up. But we have basically created what they call barriers, in effect, as sort of choke points around islands. And one of them is in the Darien Gap between Panama and South America. For some reason, about two, three, four years ago, we started seeing them come up north of there. Again, the screw room, started migrating north. There's a couple of theories. I mean, again, this is one of those where it's not entirely clear what had happened, but it looks like it's a combination of factors. Some of them related to cattle populations, some related to weather change. I mean, there's a whole bunch of different factors going on. We did have a case there was an infestation in Florida not too long ago that was affecting some of the deer population there. They'd gotten in there somewhere. They think it got there. I think the theory is through some kind of shipping lane. I do know that during COVID there were because of travel restrictions during COVID that apparently had some kind of ripple effect on the ability to deploy these flies in the sort of preventive ways. So that may be a factor, but basically it's been climbing up for the last two, three years. We have seen it climbing up and so we've known this might be coming, which, you know, which suggests we'd be extra alert for it. Although that brings us to the subject of, you know, what we've been doing at the Department of Agriculture, etc.

[A]

Well, before we get to that, I just want to stick with like, how this thing is getting here because the Trump administration, including USDA Secretary Brooke Rollins, have suggested that the real person to blame or entity to blame is the Biden administration and its so called open borders policy. Like, here's a tweet from Brooke Rollins where she blames explicitly Biden's immigration policy. She says the threat didn't appear overnight. It was the direct result of the Biden Harris administration's weak foreign policy agenda and failed immigration policies and wide open border. She notes that for decades, the New World screw worm was kept thousands of miles from the US through one of the most successful animal health programs in history, which jives with basically what you've just said and then, you know, blah, blah, blah. Enter Biden Harris. The barrier broke down in 2022. Uncontrolled illegal immigration, commerce and animal movement through the Darien Gap surged, and New World Skurm moved north into Central America and eventually reached Southern Mexico by late 2024. So is there truth to that narrative there? It sounds like some of the facts that I just read out sound a lot like what you just repeated. Is there truth? Like, should we be laying some of the blame for this breach of the barrier? I guess this outbreak in Texas at the feet of the Biden administration?

[B]

Yeah, I mean, I don't think so. Again, with a caveat that this is a developing situation, you know, and people are going to talk about this and there'll be more investigations and we'll spend some more time analyzing why this happens. So you never can be sure, but everything I've seen and read and what I've heard suggests that immigration really doesn't. That doesn't fit. It doesn't fit the timing. This is actually. Apparently we were starting to see the screw worm migrate north before these sort of Biden policies took effect. A much better, more plausible explanation is, like I said, that some of the travel and supply restrictions during COVID made it difficult to deploy some of the mitigation method and protection methods that we had. And of course, you know, it's not carried. I mean, it's very rare for humans to get it. So it doesn't. It's not likely that this migrated across the gap on humans. You know, was that will it turn out there was some role that immigration policy could have played? Maybe. I don't know. I, I think we'll find out. But at least all the sort of experts I am reading and seeing, they don't really think that explanation holds hold water. This is not about, this is not an immigration issue.

[A]

Okay, so then on the the flip side of all of this, there is also a lot of finger pointing at the Trump administration and Doge related layoffs at the USDA suggest.