Sofina is sedated, sprawled out on an examination table as four medical professionals hover over her. The 8-year-old has had Type 1 diabetes most of her life, but it seems like her normal insulin isn’t helping. Sofina’s doctors worry she might have developed Cushing’s disease and they’re taking blood samples to figure out what’s wrong.

Joseph Rosenthal, a fourth-year Harvard Medical School student, will be the one drawing Sofina’s blood. This is a bit of a unique experience for him. He’s drawn blood before, but up until recently, the process has mostly been with humans. Sofina, who resides at the Franklin Park Zoo, will be his first ring-tailed lemur patient.

Veterinarian Dr. Alex Becket coaches Rosenthal through some of the unexpected hurdles, like spotting a vein and not something that just looks like a vein.

“Now keep in mind, that with fur, it might bunch up on you and fake you out,” Becket says.

A ring-tailed lemur sits on a perch at the Franklin Park Zoo in Boston.
Meredith Nierman WGBH News

Rosenthal is part of a comparative medicine program called the One Health Clinical Elective. The program is a partnership between Zoo New England and Harvard Medical School that allows students to do a four-week rotation shadowing veterinarians at the Franklin Park Zoo and Stoneham's Stone Zoo. The elective is the only formal partnership of its kind in the country, according to Zoo New England Vice President of Animal Health and Conservation Dr. Eric Baitchman.

“[It’s] just comparing the similarities of medicine and physiology between animals and humans, and that really provides the context for the greater discussion for the concept of One Health. It’s about the intersection between animal health, human health, and environmental health, and the ecosystem health that both animals and humans share,” Baitchman says.

Harvard and Zoo New England began the program as an informal partnership when a former student, Gilad Evrony, volunteered to come over to the zoo in 2015. Evrony wrote about the moment he realized he wanted to pursue comparative health in the Journal of American Medical Association:

“Later in medical school, I read about the remarkable ways in which diseases can be prevalent in specific species but not others. I helped diagnose my family’s cocker spaniel with Evans syndrome—the co-occurrence of autoimmune hemolytic anemia and thrombocytopenia—and was intrigued to learn that Evans syndrome and immune thrombocytopenia more commonly afflict cocker spaniels, suggesting a genetic susceptibility for this breed and an opportunity to reveal some of the mystery of its cause. One of the first patients I saw on the wards in medical school had Evans syndrome. The look on the clinical team’s faces when I blurted out, “My dog has that!” was priceless. Yet it spurred me to share with my colleagues the bridges I was finding between human and animal medicine.”

Over the years, the idea grew more popular with students, and last year the zoo and Harvard formalized the program. Since its inception, seven students, including Rosenthal, have treated animals through the program, doing everything from checking up on newborn goats to vaccinating a tapir.

Joseph Rosenthal, a fourth-year Harvard Medical School student, practices drawing a blood sample from a snake.
Meredith Nierman WGBH News

What Exactly Is One Health?

While the elective is believed to be the only formal partnership of its kind in the country, the concept of One Health is an idea practiced by people around the globe.

One Health, formerly known as One Medicine, is a concept that promotes the communication between human and veterinary medical professionals, not only at the educational level but also in journals, conferences, and through allied health networks. Among other things, the idea encourages monitoring disease spread from one species to another and developing methods to stop it.

Rosenthal points to how we understand the spread of Lyme Disease in Massachusetts as an example of One Health.

“We think of [Lyme Disease] in very narrow terms as, ‘What is the number of people that are getting infected and how do we treat them?’” Rosenthal says. “Whereas broader, one might address the question of, ‘Why is Lyme disease on the rise in terms of incidence?’ [It] might have something more to do with depletion of biodiversity and the rise of certain species in the Massachusetts area that people are being more contact with that are more susceptible to transmitting it to various populations.”

Having students like Rosenthal understand One Health is more than just a way to broaden their education. Baitchman says they provide an insight into the side of the medical world veterinarians wouldn’t normally get.

“Frankly, we learned just as much from these students as hopefully we are teaching them,” Baitchman says. “These are the best of the best, right? These are Harvard [students]. We get to hear from Joseph on all the latest that he's learned on diabetes in people and that helps us consider how we might apply those treatments on our animals.”

Zoo New England Vice President of Animal Health and Conservation Dr. Eric Baitchman and Joseph Rosenthal review the x-ray of a snake. Baitchman shows Rosenthal where he see a large mass that may be causing the snakes illness.
Meredith Nierman WGBH News

From Homo Sapiens To Quadrupeds And Everything In Between

Rosenthal is squinting and shining a light into one of Sofina’s eyes, looking deep into her tiny pupils.

Lemurs, like humans and most other primates, have small pupils, making it harder to see through during exams.

“It’s like peering through a keyhole,” he mutters.

But this is one of the few situations where Rosenthal can draw from his human-based Harvard Medical School experiences. At the One Health Elective, students have to learn about the anatomy of a completely different species in a short amount of time. Confusing a clump of fur with a vein is one thing. Potentially missing a growth or a blockage in an animal is more serious, which is why the students are supervised by an experienced veterinarian.

Plus, none of these animals can communicate their aches and ailments with zoo veterinarians, forcing the staff to stay alert.

Rosenthal examines a snake as part of his training.
Meredith Nierman WGBH News

“[Animals have an] instinct is to hide their weakness. So when something is actually wrong it takes that close relationship between the zookeeper and the animal for to recognize that something is slightly off,” Baitchman says.

And these major differences are a huge factor that Rosenthal and his classmates consider when looking at the rotation. In fact, the complete change of scenery is actually a draw for the program. Rosenthal says the students face a lengthy waitlist to sign up for the experience. The fact that the elective breaks them out of usual grind that can come with med school is a huge draw.

“It's so easy in really any form of higher education to get bogged down in thinking, ‘What is the next thing I have to do that everyone does that’s going to prepare me for the next month?’” Rosenthal says. “Experiences like this are probably the most important, because they make you think differently.”

Correction: This story has been updated to reflect that the correct name of the zoo in Stoneham is the Stone Zoo.