Dr. Lisa Barrett can barely contain her enthusiasm when talking about her research, which explores the links between immune system aging and chronic viral infections, such as hepatitis C.

“The goal is to understand how infections age us,” she says. Dr. Barrett will ultimately use that understanding to find ways to boost the immune system into old age.

As a physician working in the QEII Health Sciences Centre’s Infectious Disease Clinic, Dr. Barrett focuses her practice on patients with hepatitis C and HIV. An active researcher, she leads a team at Dalhousie University’s Senescence Aging Infection & Immunity Laboratory (SAIL), with the ultimate goal of improving the health of the elderly.

“We can link the clinical with the lab research,” she says of her work.

Older people are often more susceptible to infections and show poor immune responses to vaccines, explains Dr. Barrett. This decreased immunity is often referred to as immune aging or immunosenescence. By investigating how the immune system ages and how chronic viral infections affect immune aging, she hopes to better understand how this impacts poor responses to vaccines and declining health in older people.

“When you have hepatitis C you can go from looking like a 30-year-old’s immune system to a 75-year-old’s system,” says Dr. Barrett, a graduate of Memorial University’s Faculty of Medicine who completed her residency training in internal medicine at Dalhousie University.

Dr. Barrett knows that hepatitis C accelerates the aging of the immune system, but she thinks that might be reversible. With new antiviral treatments, hepatitis C can be cured. Dr. Barrett wants to determine if that treatment can act as an anti-aging treatment as well since patients being treated with the new antivirals seem to revitalize immune cells, allowing them to thrive after the virus is gone.

“We’re looking at individual cells from hepatitis C patients to see if, how and when they regain this vitality after treatment,” says Dr. Barrett. “If we can find the mechanism, we may have the key to boosting any person’s aging immune system, whether it’s exhausted from fighting infection or simply from advancing age.”

Her lab is first looking at the influenza vaccine and how patients with hepatitis C respond to it. She hopes her research will also help her develop a vaccine strategy against the disease, which can lead to liver disease and liver cancer.

Since arriving back in Halifax in the fall of 2013, Dr. Barrett has been busy. She not only sees outpatients with HIV and hepatitis C at the QEII’s Infectious Disease Clinic, but also consults on the infectious diseases inpatient service, in addition to running her research lab. She is also developing a provincial model of care for patients with hepatitis C.

Through the Infectious Disease Clinic, Dr. Barrett and two other physicians see about 160 patients with HIV and a growing number of patients with hepatitis C. Dr. Barrett points to better screening and treatment options as some of the reasons for growing numbers. The clinic also has a nurse specialist in hepatitis C and HIV, and a nurse who works specifically with patients with sexually transmitted diseases. Outside the QEII, Dr. Barrett travels to the correctional facility in Dartmouth to treat people with HIV and hepatitis C.

Recently, Dr. Barrett started a new study in Charlottetown at the Provincial Correctional Facility. Over the next year, 60 individuals with hepatitis C will be given new antiviral drugs; she will observe how they respond to the drugs and the effects on their immune systems. Her lab is also launching a new study looking at Cytomegalovirus (CMV), a common virus that can infect almost anyone. The study will continue to delve into the connection with immune system aging and how people respond to vaccines.

“I’m hopeful my work will help people age well with fewer infections,” she says.