‘Catching’ COVID

Dr. Italo Zecca and Rachel Busselman swab the fur of a cat as part of the COVID-19 & Pets study in May 2021.

Dr. Sarah Hamer’s COVID-19 & Pets study has had a profound, global impact on our knowledge of the emergent disease, resulting in unprecedented discoveries and contributing to the scientific community’s understanding of how the virus may affect household pets.

Story by JENNIFER GAUNTT

Since the start of the COVID-19 pandemic, the United States Department of Agriculture’s (USDA) Animal and Plant Health Inspection Service (APHIS) has tracked the number of SARS-CoV-2 cases in animals ranging from cats and dogs to otters and gorillas.

Looking at this map tells a story of how one state has had considerably more positive animal cases than any other— Texas. In fact, of the approximately 363 non-farmed animals reported to have been infected by the virus since the start of the pandemic, almost one-third were from Texas.

That disparity was largely because of the work of a team led by Dr. Sarah Hamer, an associate professor in the Texas A&M College of Veterinary Medicine & Biomedical Sciences’ (CVMBS) Departments of Veterinary Integrative Biosciences (VIBS) and Veterinary Pathobiology (VTPB).

Since she launched her COVID-19 & Pets study in June 2020, her team has not only identified the first two cats in Texas that tested positive for the virus, but they also discovered the first animal carrying the British variant, B.1.1.7 or alpha, in the world.

The team never anticipated these types of results when their study first started; initially, their goal was simply to better understand how animals may be involved in the pandemic.

“As the pandemic was ramping up, the mood was gloomy, with research projects being put on pause and week after week of not knowing what to expect,” Hamer said. “At our virtual lab meetings, we started talking about what we could do to learn something new or to contribute to the science behind the pandemic. As a lab that studies diseases in animals that can cross over to people, we explored that a little bit, thinking that if there were any animals that might

be involved in transmission cycles with this virus, they would probably be ones that have really close associations with humans—our household pets." Refining that idea, they decided to sample animals living in high-risk environments, or households in which someone had already tested positive for COVID-19, to see if their pets also were infected with the SARS-CoV-2 virus.

Their early and quick success opened many doors for the team, including a partnership that quickly developed with the Centers for Disease Control & Prevention (CDC).

“When the CDC learned of some of our initial positive results, they became really interested,” Hamer said. “They deployed a veterinarian and an epidemiologist to work with us for a week, to see how our team was doing the sampling and to lend a helping hand. That solidified our common interest and sparked a collaboration that continues today.”

A MODEL OF SUCCESS

Hamer has built her career on understanding the ecology and epidemiology of infectious and vector-borne diseases that affect both people and animals.

She played a critical role in understanding the impacts of West Nile Virus (WNV) on wild bird populations at the time when WNV was first detected in the U.S., learning how bird movements can impact public health. Her work with Chagas disease also has received federal funding to examine the impact of the disease on U.S. Department of Homeland Security working dogs along the U.S.-Mexico border, among others.

“We’ve had several projects with dogs and cats for our Chagas disease work, a lot of community outreach and door-to-door type research in South Texas, working closely with the pet owners and sampling animals in household settings,” Hamer said.

These experiences with emerging infectious diseases and the novel insight Hamer gleaned from that work informed her approach to her COVID-19 & Pets research.

But the biggest key to the success of the project, she says, has been the research team, which includes faculty collaborators, postdoctoral associates, research staff, and graduate students from the CVMBS as well as Texas A&M’s College of Agriculture and Life Sciences and School of Public Health.

For example, two team members—former CVMBS postdoctoral research associate Dr. Italo Zecca (now a fellow with the Centers for Disease Control & Prevention and Hamer collaborator) and biomedical sciences doctoral student Ed Davila—initially volunteered with the Brazos County Health Department (BCHD) as part of the COVID-19 contact tracing efforts.

A formal partnership with BCHD soon emerged that allowed Hamer’s team to offer individuals testing positive for COVID-19 the opportunity to also have any pets living in their households tested for the virus. Those who opted in received a visit from Hamer’s team—appropriately protected to ensure their safety—who took fur, nasal, oral, and rectal swabs, as well as blood samples, to test the animals for the virus.

“Italo and Ed had unique perspectives from working closely in human case investigations that really helped to facilitate our project, because we were able to train the health department teams on asking the questions that opened the door for our investigation,” Hamer said.

Hamer also credits Dr. Rebecca Fischer’s (Public Health) work with the health department and the PCR and antibody testing conducted in her and Dr. Gabriel Hamer’s (Ag & Life Sciences) laboratories as contributing factors to the project’s success.

“Collaboration has been so important in this work; there are so many different dimensions—public health, veterinary health, regulatory, diagnostics,” she said. “In particular, Gabe and his team made a lot of progress on setting up protocols and approvals to work with SARS-CoV-2 in a Biosafety Level-3 environment. That is a unique capability; our unique resources here at Texas A&M allow us to actually grow the virus in cell culture in order to see if there are antibodies in the animal blood that neutralize the virus.”

Zecca prepares samples for testing. “Collaboration has been so important in this work; there are so many different dimensions—public health, veterinary health, regulatory, diagnostics.”

- DR. SARAH HAMER

Dr. Sarah Hamer, Lisa Auckland, Rachel Busselman, Dr. Italo Zecca, and Ed Davila

LEARNING IN ACTION

While their study approach set them up for success, the project was a learning experience for everyone involved.

As an active surveillance study of a disease about which very little was known when the project began, Hamer’s team initially set out to simply learn about the risk factors for pets, potential veterinary health issues, and how it relates to public health.

“We’ve learned that while we have evidence of both dogs and cats being infected, it's much more common in cats than in dogs,” Hamer said. “Even multi-pet households where you have owners with a few cats and a few dogs, it's most likely the cats that were infected; that might relate to the relationship of the cats with the owners, the animals’ different physiology, and so forth.

“Another thing is, fortunately, it's the rare case that pets are getting sick with this infection. Of the more than 600 pets we sampled, the project has confirmed infections in just under 100 animals; approximately 25% of the houses we visited had at least one infected pet,” she said. “Less than a quarter of the confirmed infected pets we’ve sampled were reported by their owners to show signs of disease, and in all of those cases, it's been very mild: sneezing, a couple cases of diarrhea, feeling under the weather, or being less active than they usually were for maybe three or four days.”

In all cases, the pets recovered on their own, which Hamer said is “a very promising message from our research.”

Beyond their findings, Hamer said this project allowed her team to practice their flexibility, especially as they encountered pets they hadn’t initially anticipated sampling, such as “pocket pets” like hamsters and hedgehogs, which required them to continuously update their research protocols and refine their skills. Their communication skills grew greatly as they worked with the public to quell concerns about participating in research, especially for a disease that has had deadly consequences.

Rachel Busselman, a doctoral student on Hamer’s team and a CVMBS first-year veterinary student, said she not only expanded upon her clinical skills through her work in the field and the lab, but she also learned the value of communicating their science with the public as Hamer and her peers interviewed with media outlets around the world to explain their findings and what they were learning as they were learning it.

The team has, thus far, published four peer-reviewed studies on their findings; has given several presentations

Auckland helps prepare sample kits.

on the work, including at the American Veterinary Medical Association convention; and has had published interviews with major news outlets in the U.S., India, Spain, and South Korea.

“While we know the work we are doing is important for science and our findings are important for the public, I saw how the media can be a helpful tool to share our work with the general public, not just the scientific community,” Busselman said.

“It’s been a privilege to be involved in a lab that asks how our expertise can be used to help add to the knowledge of a world-altering event,” she said. “I am so thankful to still be in my training with Dr. Hamer during this pandemic and watch how she uses her expertise to help and how she has persisted in the scientific process even during a pandemic.”

VIRAL RESEARCH

As the pandemic began to wane and people started returning to everyday life, Hamer’s team hit the magic 600 mark in meeting their sample size goals for their CDC funding.

While that piece of the project is over, the team has continued compiling and evaluating these data for publication—and have begun new COVID-19-related projects.

In an extension of their COVID-19 & Pets research, one project is investigating SARS-CoV-2 transmission by sampling at more regular intervals both pets and people in homes in which the human residents test positive for the virus; owners also have the option to use a device to track their proximity to their pets over a two-week period, which will allow the team to better understand potential transmission between people and pets.

In another study—funded by the Council of State and Territorial Epidemiologists—Hamer’s team is collaborating with the Austin Humane Society (AHS) and Austin Animal Center to sample cats brought to the AHS for spaying or neutering to determine if there are coronaviruses circulating among Travis County animals that could potentially pose a risk to humans.

Branching out beyond household pets, Hamer—working with CVMBS clinical associate professor Dr. Walter Cook

“It has been really nice to be a part of this project and to be a part of providing information, to answer questions, to learn about this new virus that affected the whole world. It is our small way of helping and that feels great.”

- LISA AUCKLAND

Garrett Norman holds Oreo while Dr. Sarah Hamer swabs the Norman family pet’s nose.

Samantha Norman places a COVID-19 swab into a test tube for Dr. Sarah Hamer.

and doctoral students Chase Nunez and Logan Thomas—is testing captive white-tailed deer in Texas and learned that these animals are also susceptible to SARS-CoV-2 at rates that indicated that the deer may be spreading the virus among themselves.

Finally, as doctoral and master’s students in Hamer’s lab sample wildlife for research involving vector-borne pathogens, these students are also collecting samples that are being frozen for secondary use for SARS-CoV-2 research when they’re able to secure funding.

“In a ‘One Health’ perspective, we know the health of people, animals, and the environment is all intertwined,” Hamer said. “So to most fully understand the ecology of SARS-CoV-2 and other emerging diseases, we need to incorporate humans, animals, and the ecosystem in our research efforts.”

As the team reflects on their experience, there is a feeling of both pride and accomplishment.

“It has been really nice to be a part of this project and to be a part of providing information, to answer questions, to learn about this new virus that affected the whole world. It is our small way of helping and that feels great,” said research associate Lisa Auckland. “We’ve heard lots of great stories from the people we visited—not all were related to COVID, but it has been great to connect with the community and hear the stories that people want to share with us.”

Hamer said it has been important that the staff and students on her research team feel fulfilled by their work, but she also acknowledges that it’s been an intellectually satisfying project as they worked to drive knowledge forward.

“We know that after SARS-CoV-2 is under control, there will be a ‘next’ emergence of another zoonotic pathogen, so it’s important to train our students not to be experts on any one disease but to have the skillset to apply their epidemiology and biomedical sciences background wherever it is most useful to help improve human and animal health,” she said.

“I am so proud of the whole team and the fact that everybody was able to quickly create new roles and work together,” Hamer said. “As a mentor, I could have never expected that, because there is some risk associated with going to these houses, even though we had appropriate PPE and the best protocols. Nobody had to do this. So just being a mentor on a team where there was so much willingness to step up to the plate in the face of the pandemic has been really satisfying.” ■