Member Spotlight: Jimmy Bernot

By Kelly Weinersmith

Dr. Jimmy Bernot recently finished postdoctoral positions that brought him from the Smithsonian National Museum of Natural History, to the Natural History Museum in London, to the Senckenberg German Center for Marine Biodiversity Research! I connected with Jimmy over email while he was hanging out in DC before moving to Connecticut to start as an Assistant Professor at UConn. Jimmy studies parasitic copepods, and in the email interview below we chat about weird copepods, Ian Mckellan, getting infected by hookworms, and more. Enjoy!

Q: Did you have an "a-ha!" moment when you realized you wanted to be a parasitologist? If so, what was it? 

A: It wasn’t a singular moment, but over the first few years I was studying parasites (i.e., shark tapeworms) I became more and more fascinated by their host associations. Most organismal biologists study a group of animals, and, in part, that involves studying them in the context of their habitat. But with parasites, their habitat is in large part another organism. I think that just makes parasites way more interesting than any other group of organisms!

Q: One of my favorite things about copepod parasites is the incredible diversity of their body plans. What is your favorite copepod parasite overall? And which copepod parasite seems "weirdest" to you (and of course I mean that in the nicest way possible...)? 

A: One of my favorite species is Lernaeolophus sultanus, a member of the family Pennellidae. Pennellids exhibit many of the most interesting features of parasitic copepods: they have lost most of their appendages and external segmentation—they often look more like worms than arthropods; they are mesoparasitic, living with their heads (the branchy part at the top left of the photo) embedded into their fish hosts; and they are also some of the only parasitic copepods with a multihost lifecycle: their definitive host is usually a fish but their larvae live on pelagic molluscs. They are really amazing and surprising animals!

Lernaeolophus sultanus

Image credit: Natural History Museum, London.

Without a doubt, members of the genus Sarcotaces are some of the weirdest copepods. Adult females look like blobs that are about the size and shape of a large grape. Adult females lack all appendages and external segmentation—you would be hard pressed to identify this as an arthropod!

Some species of Sarcotaces live under the skin of fish but others swim up the rectum and live in an out pocketing of the intestine that they form there. Adult males are tiny things that can be less than 1/100th the size of the female, and still look somewhat look like a copepod.

Sarcotaces antimori

Image credit: Natural History Museum, London.

Q: What is the most exciting thing that has happened to you as part of your parasitology career? 

A: I love being a scientist and I love my job. I have gotten to go around the world to collect parasites, to attend conferences, and to meet some incredible people. I feel extremely grateful to have found a career that fuels my curiosity, provides me with a diversity of problems to solve, challenges me, and brings me into contact with remarkable people.

Beyond that background level of excitement, there have been so many interesting experiences. Some particularly formative ones came during biodiversity surveys when I encountered some particular host individuals. The first was a sunfish that seemed perfectly healthy, but upon dissection I saw at least 1/3 of its liver was taken up by metacercaria. The second was a small frog that I dissected only to find was still moving—more than 20% of the frog’s biomass was taken up by 2 trematodes in its intestine! When dissecting several small sharks for my Master’s research, I found a few emaciated looking individuals that I thought were probably heavily infected with tapeworms, but it turned out they were uninfected, while the largest, most robust individual turned out to be heavily infected. These experiences demonstrated how impactful, yet surprising, parasites can be. I would not have thought a sunfish or frog could be so heavily parasitized yet be living apparently normally. Clearly those parasites must be affecting their host, but not always in the obvious ways we anticipate. I think it also goes to show that it can be very difficult to know what is going on inside an organism when looking from the outside, and I think there is a larger life lesson in that too.

Q: What is your favorite book? 

A: I read a ton of fantasy and science fiction. It is one of my main pastimes. If I had to choose a favorite, I’d say the Lord of the Rings. I love the books and reread them regularly—they paint a world that is so rich. I am always finding new things to appreciate in them. I love the Peter Jackson film trilogy too. I bumped into Ian Mckellan at a bar in London last year and was pretty star struck 😂

Q: What advice do you have for budding parasitologists in undergrad or grad school? 

A: (1)  Don’t forget to take stock of your own learning and how far you’ve come! One of the great things about academia and science in general is that there is always more to learn and discover. But that also means we can feel discouraged when we feel we don’t know enough or haven’t perfected a technique. As we learn more, we keep moving the goalpost on to the next challenge, and we forget to celebrate our progress. I suggest periodically (at least a few times a year or more often if you are feeling discouraged) doing the following exercise: say it is December 1, ask yourself if you could travel back in time to September 1 and tell you past-self all of the progress you had made between September and December, how would your past self feel? Even when we are feeling discouraged in the present, chances are your past self would be very pleased with how far you have gotten. You’ve probably made a lot more progress than you realize—we often just have trouble seeing that progress ourselves.

(2)  Take lots of notes! You will never regret keeping a detailed notebook of your research projects, meetings, etc. On the other hand, I can guarantee that months or years later you will forget some things you thought were so obvious that they didn’t need to be written down. When in doubt, write it out! Your future self will thank you.

Q: Purposefully infecting oneself with parasites used to be something like a right of passage for parasitologists. Thankfully, that's pretty rare now. But you've gone through this ancient initiation ritual! Would you tell us which parasite you hosted, why you volunteered to be infected, and what the experience was like? 

A: I’ve been a host to several parasites but only one of them was intentional: the hookworm Necator americanus. I was experimentally infected as part of a hookworm vaccine trial that took place at George Washington University. I enrolled in the study for a few reasons: (1) I thought it would be a good story to tell when teaching parasitology, (2) I was interested in experiencing what a hookworm infection (and clinical study in general) is like, (3) the risks were low and the experimental vaccine could help the hundreds of millions of people that are infected with hookworm globally, and (4) I got paid around $1,000.

Here is what happened. For people that are interested, I wrote a Twitter thread about this and included some pictures. Over the course of several months I was given 3 doses of an experimental vaccine. After that, that vaccine was tested by infecting me with 50 hookworms larvae that penetrated my skin from a patch of gauze I wore on my wrist for 1 hour. I felt a tingling sensation under the gauze patch as the larvae sensed fatty acids in my skin and release proteolytic enzymes to make it easier to slip between my skin cells and into my blood vessels. It got very itchy! After an hour the gauze was removed and I went about my day as a faint rash developed where the worms were applied. Over the next week the rash from the worms and my immune response enlarged. The itch was more intense than any I’ve experienced—much worse than poison ivy. I slept with Benadryl cream next to my bed because the itching would wake me up in the middle of the night. At this point, it was interesting to consider that the larval worms were now riding around my circulatory system like a tube slide at a water park. At least that’s how I pictured them. This was during COVID lockdown and I joked that I appreciated the company and started using the royal “we”. Besides the itchiness I didn’t have any other side effects, but, interestingly, I didn’t experience any seasonal allergies that year. After a few months, I started giving fecal samples to the study team every 2 weeks so they could check for worm eggs. The number of eggs let them estimate the number of worms I had. 76 days post infection and eggs appear for the first time. My worms were alive and mating apparently.

After about 6 months with the worms, it was time for their stay (and my part in study) to end. Fortunately, it is pretty easy to cure hookworm as long as you aren’t being continually infected. I was given a triple dose of Albendazole to clear the infection. About a year later, after the study was completed, I was informed that I was given one of the experimental vaccine/adjuvant combinations, not the placebo, and that one of vaccine/adjuvant combinations was significantly protective. It was really interesting to experience research from the other side – as a study participant rather than a researcher. I got to take my background as a scientist to this side of the experiment and ask questions each week to the nurse/doc I talked to. I learned a lot! We have so many medicines, treatments, and vaccines that make our lives so much easier—it's easy to lose sight of all the work and self-sacrifice that goes into making them safe and effective. I got to witness that here and I really appreciate that perspective. It was a very interesting experience and I have no regrets!