SC Connecticut News

Heidi Zapata, MD, PhD, assistant professor of medicine (infectious diseases) at Yale School of Medicine, has a deep interest in microbes—bacteria, viruses, fungi, and parasites that are too small to be seen with the naked eye. “That’s what led me to infectious diseases,” she said.

Zapata's curiosity increased when she observed that the same microbe could cause mild disease in one patient and severe sepsis in another.

“I truly want to understand the individual immune response,” she said. “Why are some people completely asymptomatic while others die from the same infection?”

Her research aims to understand how aging, HIV infection, and comorbid conditions affect the innate immune response in humans. Currently, she is studying how the adipose tissue immune microenvironment contributes to the body's overall immune response.

In a Q&A session, Zapata discussed factors influencing a person's immune response, ways to boost immunity, and her aspirations for personalized medicine.

When asked why individuals respond differently to infections, Zapata noted: "Everyone is different. For example, some older adults are running marathons while others are sick with numerous comorbid conditions. There is an incredible amount of human variation when it comes to responding to infections. We all have an individual immune response, and we need more research to understand why that is."

She also highlighted various factors that influence a person’s immune response: "Evidence shows that men and women respond differently to infection because different parts of their immune systems are enhanced. Men have a more robust innate immune response while women have more of what we call an adaptive and memory immune response. So even biological sex plays a role."

Age is another factor: "During the COVID-19 pandemic, older adults had more severe disease than young people. Another example is the West Nile virus which is going around right now. Some people don’t even realize they have the virus while others, especially older adults, will develop severe symptoms such as meningitis and encephalitis."

Comorbid conditions like diabetes and an individual's level of immunocompromise also play roles: "Ongoing cancer, a transplant or drugs that change your immune system all contribute to how we respond to a microbe."

Regarding ways to increase immunity, Zapata suggested simple measures: "First of all, it’s important to be on top of your medical conditions. If you have diabetes or high blood pressure make sure they’re well-controlled."

She also recommended vaccinations: "Consider getting vaccinated—there’s a new COVID booster flu shot and RSV vaccine—especially if you are an older adult."

Dietary changes can help too: "Eat less greasy fatty foods which can cause inflammation. A lot of investigation has been done on the Mediterranean diet and its anti-inflammatory effects. Eating healthy makes a difference."

Ultimately, Zapata hopes for tailored interventions: "A vaccine for a healthy young adult should be different from one given to an older person who’s immunocompromised."

"It’s important that this line of research continues because COVID-19 is probably not our last pandemic," she concluded.

Yale School of Medicine's Department of Internal Medicine Section of Infectious Diseases engages in comprehensive patient care research and educational activities for various infectious diseases.

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