UF researcher tracks bacterial genetic diversity in fight against tuberculosis

A group photo, with Dr. Marie Nancy Séraphin and nine tuberculosis clinic staff smiling and gathered around a table.
EPI member Marie Nancy Séraphin (sitting and wearing glasses) with staff at a tuberculosis clinic in Ghana. (Courtesy of Marie Nancy Séraphin)

Since June 2022, infectious disease expert Marie Nancy Séraphin, M.D., has been researching tuberculosis in Ghana. This disease, which primarily affects the lungs, is a leading infectious killer and caused 1.3 million deaths worldwide in 2022.  

Although tuberculosis can be treated, certain strains of Mycobacterium tuberculosis, the bacteria that causes the disease, have become resistant to antibiotics over time. Séraphin, a research assistant professor at the University of Florida’s College of Medicine and member of the Emerging Pathogens Institute, is studying how the genetic makeup of a tuberculosis bacterial population changes during transmission. Understanding the diversity of the bacteria could help public health experts in treating and reducing the spread of tuberculosis.

A photo of the front entrance of the tuberculosis clinic. The sun is out and the sky is bright blue.
The clinic where Séraphin conducted her study also serves as a teaching hospital, called the Korle Bu Teaching Hospital. (Courtesy of Marie Nancy Séraphin)
Two men sit in office chairs, facing each other. One of them is looking at some notes in his lap.
By partnering with a clinic, Séraphin is able to collect data from patients even before they receive an official diagnosis or begin treatment. (Courtesy of Marie Nancy Séraphin)

The bacteria that infect a patient with tuberculosis are not genetically identical. Every time the disease is transmitted, the bacterial population goes through a selection process as it adapts to the new host. Strains of Mycobacterium tuberculosis that successfully fended off one patient’s immune system may turn out to be weaker in a new host, so the dominant strain may change over time as the infection progresses.

The view down a hallway in the clinic. There are lots of tall, open entrances and plenty of natural light. The bottom half of the wall is painted light yellow while the upper half is painted white.
Of the many respiratory infections treated at the clinic, tuberculosis is the most common. (Courtesy of Marie Nancy Séraphin)
A photo of one of the tuberculosis clinic's open air areas: two big benches sit on a long balcony. Trees can be seen in the distance.
Patients providing sputum samples go to open air spaces to do so. (Courtesy of Marie Nancy Séraphin)

To understand how the genetic diversity of Mycobacterium tuberculosis changes with each transmission, Séraphin worked with a tuberculosis clinic to gather sputum samples from patients. Sputum, sometimes known as phlegm, is a mixture of saliva and mucus coughed up from the respiratory tract.

To provide a sputum sample, patients at the clinic were instructed to cough deeply to expel material from their lungs into a cup. This not only provided researchers with a sample to study but could also be used to confirm a tuberculosis diagnosis.

Inside the clinic, a woman wearing a blue dress speaks to a man in a striped button-down shirt. They are both wearing paper face masks.
Dr. Jane Afriyie-Mensah, in blue, is Séraphin’s collaborator and principal investigator responsible for patient enrollment in Ghana. Afriyie-Mensah explains enrollment procedures to one of the research coordinators. (Courtesy of Marie Nancy Séraphin)
A man wearing a blue T-shirt is photographed from behind. Across the center of the back are the words "TB is Treatable, Seek Early Help."
Every year, the chest clinic at the Korle Bu Teaching Hospital in Ghana makes T-shirts and hosts “Tuberculosis Day,” an event that helps promote the early detection of tuberculosis. (Courtesy of Marie Nancy Séraphin)

In addition to treating patients, the clinic also has public health education campaigns. While some people’s immune systems are successful at fighting off tuberculosis, patients with weakened immune systems are at greater risk of infection. Patients often receive HIV and tuberculosis diagnoses at the same time, which contributes to a stigma that may cause patients to delay seeking much-needed help.

Two women smile for the camera in a selfie. Both are wearing paper face masks.
Séraphin (left) with her colleague Dr. Ivana Parker, Assistant Professor of Biomedical Engineering at the University of Florida, who is also conducting research in Ghana. (Courtesy of Marie Nancy Séraphin)

After about a year of travelling to Ghana and enrolling study participants, Séraphin has reached her goal of gathering data from 150 patients. She took one final trip to wrap up the first phase of the study. She worked with the clinic staff to make sure any missing data points got filled in, data was appropriately collected and validated, and that everyone who provided data signed an informed consent form. Now, she will begin analyzing the data.

Séraphin’s research in Ghana is a collaboration between the University of Florida, the University of Ghana, and the Korle Bu Teaching Hospital.

Written by: Jiayu Liang