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.
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.
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.
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.
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