University of South Florida


A woman in a suit.

Karen Ruiz-Ayala, MPH. (Photo courtesy of Ruiz-Ayala) 

The voyage of one COPH alumni through public health

Originally from Puerto Rico, Karen Ruiz-Ayala, a USF College of Public Health alumna, moved to Spring Hill, Fla. when she was young and discovered her passion for public health through reading.

“I was very interested in medical history and stories. An important introduction to the topic of public health was the book “Deadly” by Julie Chibbaro. It’s a fictionalized story about a young girl working as a lab assistant in New York at the turn of the century investigating a strange illness outbreak that would later be known as the famous Typhoid Mary case.,” she said.

Ruiz-Ayala’s decision to attend the COPH was influenced by its emphasis on research opportunities, notably the COPH Activist Lab, where she served as a student board member.

 "Dr. Karen Liller, the director of the Activist Lab, was a big inspiration,” Ruiz-Ayala said. “She made me feel like I could accomplish anything I set my mind to and was a role model for me."

Amidst her academic pursuits, Ruiz-Ayala faced the challenge of adapting to the COVID-19 pandemic. Reflecting on this experience, she shared, "We were sent home just a few weeks into my first semester at USF, and it was surreal learning about public health and its history while living through a pandemic as well.It was one of the best lessons about socioeconomic determinants of health and well-being that I could have ever had.”

Transitioning from academia to practical application, Ruiz-Ayala began her public health career at Hillsborough County Mosquito Management, where she worked as a mosquito control technician. In 2023, Ruiz went on to earn her master of public health, with a concentration in epidemiology from the University of Glasgow, in the United Kingdom.

Currently, Ruiz-Ayala is the public health officer for Carnival Cruise Lines, working onboard the Carnival Paradise.

a woman on a ship

As part of her integrated pest management duties, Ruiz-Ayala waits for ship clearance from local port authorities in order to go outside and check that the rat guard was placed properly to ensure the ship can avoid rodents coming onboard via the mooring lines. (Photo courtesy of Ruiz-Ayala)

In her role, Ruiz-Ayala said she ensures compliance with disease prevention and control measures, including COVID-19 protocols, and participates in outbreak management teams. She also oversees vessel compliance in areas such as sanitation and pest management, conducting audits and inspections to uphold public health standards.

“A passenger once asked me what I do onboard. I started to answer with a generic, ‘I’m the public health officer and my main responsibility is ensuring we prevent any illness outbreaks,’” Ruiz-Ayala said. “But our senior doctor cut in and said ‘She’s like the doctor for the whole boat. When people come to see me for something I can only ensure that individual is healthy, but she ensures the entire boat stays healthy’.” 

Ruiz-Ayalya also said she is involved in all departments including management both shipboard and shoreside.

"Effective communication for all departments is key to addressing public health concerns and maintaining a safe environment onboard," she said. "This means that I am involved in recreational and portable water, to the engine room, bridge, deck, housekeeping, food service and integrated pest management, as each one plays a different role in the health and safety of everyone onboard."

Despite the demanding nature of her work, Ruiz-Ayala said she finds fulfillment in the diverse responsibilities of her role.

"From disease prevention and control to vessel sanitation compliance and integrated pest management, I get to experience a wide range of public health practices," she said. "This diversity allows me to continually learn and grow professionally while making a meaningful impact on the health and safety of guests and crew."

a woman next to a ship

Ruiz-Ayala is in front of the ship Paradise docked in Nassau, Bahamas in April 2024. (Photo courtesy Ruiz-Ayala)

She also pointed to travel as being one of the best perks of this job. “On my current itinerary, I travel in the Caribbean and the Bahamas. Seeing beautiful islands that so many people only dream of visiting in my everyday life is a special memory that I will always have.”

“Public health allows us to look at things from the bigger picture, address systemic issues, implement preventive measures and ultimately improve the overall well-being of communities and populations, making a lasting impact beyond individual health outcomes,” Ruiz-Ayala said. “By understanding the broader factors influencing health, we can create more effective interventions and policies that promote health equity and sustainable change.

In the future, Ruiz Ayala said she would like to transition to working more with integrated pest management. “That was my master’s thesis and one of my specialties with my previous work experience,” she said. “Most public health officers have a specialty such as water, sanitation, medical and mine just happens to be pest management.”

Fast Five

What did you want to be when you grew up?
A doctor.

Where can we find you on the weekend?
Working. I work 4 months at a time, 10 hours a day, with no days off. I usually don’t know what day of the week it is, only if we are in Bimini or Cozumel.

What is a superpower you would want to have?
Teleportation so I could be with the people I love more easily while I’m working onboard. 

What is the last book you read?
“Done and Dusted” by Lyla Sage.

What is your all-time favorite movie?
“Mamma Mia”. 

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About Department News

Welcome to the USF COPH news page. Our marketing and communications team is entrusted with storytelling. Through written stories, photography, video and social media we highlight alumni, faculty, staff and students who are committed to passionately solving problems and creating conditions that allow every person the universal right to health and well-being. These are our stories.