51��ɫ

By Amy Matzke-Fawcett

For most students, a practicum is a final step toward graduation and a chance to gain hands-on experience in their field of study. For Darian Dean ‘22, it also meant turning her passion for public health into an unexpected research opportunity: tick borne illness.

Dean, who is set to graduate with a master’s in public health in August, works as an infection prevention associate at Children’s Hospital of The King’s Daughters (CHKD) where she investigates hospital-acquired infections and creates protocols to keep patients safe. But when it came time to complete the 200-hour practicum required for graduation from her Master of Public Health (MPH) program, the challenge was clear: how would she balance a full-time job with a meaningful practicum placement?

Her research led her to Holly Gaff, Ph.D., professor and chair of biological sciences in the College of Sciences at 51��ɫ Dominion University. Despite being in different departments, Dean says Dr. Gaff welcomed her with open arms because of the connection between tick-borne illness and public health.

“I read some of her papers and couldn’t believe she had a lab right here,” Dean said. “The idea that this niche work was happening in my own backyard was incredible.”

Dean became one of the student researchers on the 51��ɫ Tick Team, a group that conducts tick surveillance across Virginia. Established in 2009, the team visits designated field sites monthly and uses a standard flagging technique — literally dragging cloth across vegetation — to collect ticks questing for a host. The fieldwork was a breath of fresh air for Dean, who was used to working behind a desk.

“Being out there, collecting ticks, logging the data and working in the lab — it was all completely new,” she said. “I’d never done research like this, and the team was so welcoming. I learned what to wear in the field, how to collect properly and what happens to the samples once they’re back in the lab.”

The driving force behind her desire to join the Tick Team comes from a concept she learned during undergrad in a class led by Leslie Hoglund, Ph.D., clinical assistant professor for epidemiology, biostatistics and environmental health: One Health. The class takes an interdisciplinary approach to public health that emphasizes the interconnectedness of human, animal and environmental health, a concept that has stuck with Dean throughout the years. 

"The 51��ɫ Tick Team has greatly benefited from having MPH students in the lab over the years, and Darian is one of the top MPH students we have had,” Dr. Gaff said. “The students come with a lot of knowledge on the theory of public health, but they get a chance to learn the challenges of active surveillance and public health outreach through work on ticks and tick-borne diseases."

For Dean, the fieldwork is just the beginning. Once students return to the lab, each tick is frozen to preserve its DNA, cataloged in a detailed database and eventually tested for pathogens. This hands-on exposure to both the field and molecular sides of epidemiology led Dean to the question that was ultimately the subject of her practicum’s final project: how do changes in the environment affect tick populations?

For the answer, she analyzed tick data going back to 2010 and cross-referenced it with National Oceanic and Atmospheric Administration (NOAA) weather reports. Her findings suggested a link between major rain events and decreased tick populations in the following three years in the Tidewater region. 

Dean investigated the effects of environmental change, through the lens of major weather events, on lone star tick populations in Virginia’s Tidewater region. As one of the most common human-biting ticks in Virginia, the lone star tick has the potential to carry diseases such as Rocky Mountain spotted fever, alpha-gal syndrome, ehrlichiosis, heartland virus, rickettsia parkeri disease and tularemia. Using NOAA's storm event database, Dean examined the various major weather events with flood and heavy rain events being the most common occurrences. 

Her findings show that for every flood or heavy rain event in that timeframe, the population of lone star tick counts decreased by approximately 16 ticks. The findings could lay the foundation for predictive modeling of tick populations in response to weather, Dean said. 

“It all ties back to One Health,” Dean explained. “Environmental changes affect animal populations, which in turn impact human health. That’s the lens I use for everything now.”

Looking ahead, Dean plans to turn her practicum into a manuscript for a submission to a public health journal to share the findings with other researchers. She also plans to incorporate what she’s learned into her future career plans.  

“My biggest regret is not knowing about this opportunity earlier,” she said. “It’s changed how I see public health and what I want my role in it to be.”

For more information on the 51��ɫ Tick Lab and how to submit your own tick for testing, visit the 51��ɫ Tick Team