‘Yikes, I’m A Host’: What It’s Like To Have Parasitic Eye Worms

‘Yikes, I’m A Host’: What It’s Like To Have Parasitic Eye Worms

It’s not every day that you turn into a medical curiosity. But that’s exactly what happened to Dianne Travers Gustafson, a retired medical anthropologist and public health researcher from Nebraska. In February 2018, her eyes had the misfortune of becoming infected by a particular kind of parasitic roundworm spread by face flies. She likely fell victim to the parasite while trail running along California’s Carmel Valley.

The “fluke” incident made her only the second human host of the cattle eye worm ever documented. A scientist through and through, though, Gustafson helped co-author a report detailing her peculiar case, which was published in October. Gizmodo reached out to Gustafson to talk more about her harrowing experience, why she felt the need to publicise it, and whether she’s now become a fan of goggles. This following conversation has been edited and condensed for clarity.

Gizmodo: Can you take us through the fly-smashing experience that likely exposed you to these worms?

Gustafson: Well, I don’t think I’d call it fly-smashing.

[My husband and I] are regular trail runners. We trail run at least a couple times a week, and this was a trail we’d run endless times. It’s a very steep trail, with these little hairpin turns, so you can’t really see what’s ahead until you’ve made the turn. But on that particular turn, we knew a rattlesnake lived there. And I was watching the ground, trying to stay out of his way. So when I got past that part where the snake tends to be, I looked up and I was just headed into what I would call a cloud of flies.

We live on a farm, and we’ve had cattle, so it’s not that we don’t have flies. And I’ve had many potential exposures over time right here in the farming ranching areas [of Nebraska]. But I’d never seen anything quite like this. Anyway, before I knew it, I was in the midst of it. And they were in my eyes and mouth and it was just a matter of getting them out, wiping them off from my eyes. But I remember thinking, “Oh, I hope there’s nothing in here.” Because the article about the first woman in Oregon had just been published and I had read it. But then that went out of my mind, because the chances were low. And when I got home, which was probably hours later, I watched my eyes carefully. And that was it.

Gizmodo: The discovery of the eye worms came about a month later. When did you know something was up?

Gustafson: Well, I started to have more watering in my eyes, which of course was just food for the nematodes, so they were happy. But I wear contact lenses—dailies—and sometimes with contacts, because of dry air or other things, you can get a little extra teary. So I probably discounted the early symptoms. Then I thought that I must have an eyelash stuck in there, and I kept trying to wash it out. Then I thought, maybe it’s an ingrown eyelash. And so I took a pen light and magnifying mirror to look at my right eye. And what I saw were three little glittering, translucent things moving across my eye.

Gizmodo: What did it feel like seeing these little worms in your eye?

Gustafson: My professional area of research has been public health, which I’ve practiced through the years. So my first actual thought was, “Wow, fascinating. This is interesting. What in the world is going on here?” Then a second later, I was like, “Yikes, I’m a host.” You know, in public health, we use the epidemiological triangle of hosts, environment, and vectors, with the flies being the vector in this case. So I’m a host—I’m a host for some sort of nematode. And then I thought, I want them out of there!

So I tried irrigating them out and I’ll tell you, these little buggers get stuck to your eyeball. I mean, they live in the tear, but they’ll hide if they feel something coming after them.

Gizmodo: You did eventually get all four worms out from both eyes, both by yourself and with the help of an ophthalmologist, with no lasting physical injury. But when did you actually start to feel safe?

Gustafson: Well, I’m still very sensitive to any sensations in my eyes. But finally, it was like, ok, it’s done, because their reproductive cycle is about three to four weeks. So when I got past that point, I knew I was in the clear.

Gizmodo: The other unusual aspect about this is that typically, patients don’t co-author their own case reports. Obviously, you’re a scientist already, but what made you want to talk about your experience publicly?

Gustafson: Well, because I’m in public health. And people need to know of anything out there that’s shifting in our health arena. We have these emerging diseases, with all these changes to the ecology around the world. And in terms of zoonoses [diseases spread from animals to people], the things that have always been in animals we’re starting to see transfer to humans, and likewise from humans to animals. So we really need to trace and track these things, and I’m part of that system.

But people need to understand this from an experiential perspective, not from a sensationalistic perspective. So if they have something that feels like an eye irritation they can’t get rid of, then they should go to their health care provider and have them take a look. Now, it’s not likely that it’ll be a nematode, but if it is, we need to know that. And they need to resolve that, because these can really damage the cornea and compromise their vision. But in order for us to know what’s really going on, scientifically, we need to have that data.

I think the other thing is that having a person telling their story helps reduce the sensationalizing of it. I do want everybody to feel like yeah, you know, these things happen in life. And we do need to know more about this. But also, you’re not at high risk. Most people don’t live on a ranch or a farm. And even though I have continuous exposure, with the cattle here, I had never had a problem until I saw that cloud of flies.

Gizmodo: You do travel to that same area regularly. Will you be taking any precautions in the future? And what would you recommend others do to avoid your fate?

Gustafson: Oh, I immediately did after it happened. I’ve gotten these fitted athletic sunglasses, and I do not go trail running without them on. That said, when people ask me about this, I do tell them that those glasses are the best physical precaution. But also, you still need to watch out for those rattlesnakes. And if there’s a cloud of flies, make sure you don’t run into the cloud of flies.

Again, that’s unlikely to happen. I’m 70 years old and I’ve been running forever, and that was the first time I’ve ever seen a cloud of flies like that. On the other hand, maybe these clouds are something that’s starting to happen more often. So we really do need to track these flies, and the cattle need to be more closely observed and treated too.