After the unfortunate loss of 13-year-old Beco, an Asian elephant, the Columbus Zoo opened its own unique on-site DNA lab, making it one of only four labs in the US able to test for elephant endotheliotropic herpesvirus (EEHV), a common disease affecting elephants across the world. With weekly testing and monitoring, and collaboration with both the scientific and local community, the lab hopes to prevent losses like Beco’s in the future.
The lab, located at the Columbus Zoo, employs a staff of veterinarians, veterinary technicians, and a laboratory technician who work with both blood and trunk wash samples on a weekly basis. Before the lab opened, samples would have to be shipped to the Smithsonian’s National Zoo or driven the seven hours in case of an emergency.
“It’s incredibly important to catch EEHV early,” says Dan Wallon, a veterinary technician at the lab. “By being able to test these samples on-site, we can catch EEHV early before clinical signs present themselves and it may be too late for treatment to help.”
EEHV is a herpes virus endemic to Asian and African elephant populations and can present itself in populations in zoos and in the wild. While most EEHV infections are asymptomatic and do not require treatment, one version, EEHV hemorrhagic disease (EEHV HD), does result in symptoms and is fatal without treatment. Younger elephants, between the ages of one and 15, are especially susceptible as they can be exposed to the virus during their youth as early maternal antibodies are waning. EEHV HD can kill an elephant within 24-48 hours from the onset of clinical signs, which include stiffness, a reluctance to get up, cyanosis, and vascular seepage, among other symptoms. The ultimate cause of death is cardiovascular shock.
The quick progression from clinical signs to fatality is one of many reasons why it is important to have an on-site lab in zoos where elephants are present. Another important reason is the unpredictability of the disease itself. The Columbus Zoo lab tests trunk wash samples weekly with the help of trained keeper staff who perform the trunk washes and deliver the samples to the lab. Testing trunk wash samples informs staff on shedding and potential exposure to the virus. The process includes injecting a sterile saline into the elephant’s trunk, which the elephant then blows out. This sample is then taken to the DNA lab where they process the shedding for the EEHV virus.
When asked about the trunk wash process, Wallon admits that “it’s a bit of a dirtier process than the blood samples, but it’s an important testing step as the level of shedding of the virus can vary between elephants.” Wallon, typically accompanied in the lab by some good music to help the day go by, performs a rigorous extraction process on the trunk wash samples to get down to the DNA, including amplification, master mixing, and plating in a thermocycler. Although the constant processing of these samples may seem arduous, it allows for the opportunity to monitor trunk wash samples over time, another unique feature available thanks to the lab being on-site. Technicians are now able to work on quantification of data points from trunk washes over time.
The quick progression from clinical signs to fatality is one of many reasons why it is important to have an on-site lab in zoos where elephants are present.
When it comes to EEHV, it can be shed asymptomatically by elephants in a herd. When this shedding occurs in a contained ecosystem, another animal could be exposed and develop the infection within two to three months. Trunk washes allow the monitoring of these shedding events and allow the staff to be prepared for a potential sick elephant. Testing blood samples is the only way to detect EEHV early, as they can show an uptick in blood viremia up to 28 days before clinical presentation. These early detections allow the staff to begin aggressive treatments immediately, which involves lengthy 24-hour care. Even with treatment, it isn’t guaranteed that an elephant will survive as EEHV has a 60 to 70 percent mortality rate. However, no elephant will survive EEHV HD without treatment, so catching the signs early and giving these highly endangered animals a chance is of the utmost importance.
An on-site DNA testing lab is an expensive project, and trying to find the budget for it had been a priority for many at Columbus Zoo. The lab was in the process of being developed and the outpouring of donor support allowed the lab to open only a couple of months after Beco’s loss.
Another important relationship to the zoo is that of the Smithsonian, whose partnership is and has been invaluable in the day-to-day operations of the lab. The Smithsonian developed the process for much of the EEHV testing and made it what it is today. They also helped build the lab from the ground up, assisting with training and lab design. Zoo staff still interact and collaborate with the Smithsonian on a weekly basis, validating results and working together on other research projects.
This kind of collaboration-based science is what really makes the Columbus Zoo DNA lab unique, according to Wallon: “Obviously getting to work with elephants daily is incredibly unique and special, but the collaboration aspect of the lab is what really sets us apart.” Collaboration has been important since the lab’s inception, with the entire zoo family, from upper management to volunteers, being excited and supportive of the project. Along with internal support from the Zoo itself, the lab couldn’t work without the collaborative efforts between the lab staff and the keeper staff, the latter of which are trained to provide the weekly blood and trunk samples and play a vital role in keeping the elephants healthy and safe. There has also been an outpouring of support from the community, whether through donations or just pure interest in the lab and its work. “Oftentimes, research labs get pushed to the back corner until it comes time for results,” remarks Wallon. “So, it’s nice to see so much support for the lab and our work towards the well-being of the elephants.”
The elephant in the room seems to be the lingering question of whether labs like the one at Columbus Zoo will become more common over time. Things do seem to be moving in that direction and quite a few other zoos across the US are in the process of developing these on-site labs, but the financial and collaborative requirements necessary make opening a lab of this kind a lengthy endeavor. However, it is important to see more labs of this kind open. Elephants are a highly endangered species, and zoos should be doing everything possible to make sure they are not passing away from EEHV at alarmingly high rates in places where it can be detected and prevented. In Wallon’s own words, “Ideally, an on-site DNA lab should become standard if a zoo has elephants because you will, at some point or another, need that kind of care to keep them healthy. In the grand scheme of housing elephants, the value of their lives, based on how rare and long-lived they are, far outweighs the cost of opening and maintaining a DNA lab.”