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Rising Stars of Infectious Diseases: A Five-Part Series. Part Three: Heidi Zapata, MD, PhD

July 06, 2022
by Jane E. Dee

Heidi J. Zapata, MD, PhD, can attest to the fact that the COVID-19 pandemic was stressful for health care providers. For Zapata, assistant professor (infectious diseases) at Yale School of Medicine, the pandemic meant that she and her colleagues prioritized clinical service - caring for COVID-19 patients - over everything else.

“I did a ton of service right in the beginning when it was really bad,” Zapata said. “We didn't know a lot back then, so we just poured over every case.”

Zapata studies the immune response to disease and how it’s influenced by age and body weight as well as factors such as HIV infection, diabetes, and hypertension. “These will all combine to affect how you eventually respond to a microbe,” Zapata said.

She is especially interested in how obesity affects a person’s immune response, which was highlighted during the pandemic as people with COVID-19 who have obesity typically did worse than people without obesity. Her current research focuses on understanding the contribution of fat to our immune response by using single-cell RNA sequencing on the adipose (fat) tissue. “It's basically where you sort single cells from the adipose tissue and then you look at all the genes that are in that cell. It helps you understand the cellular community better,” Zapata said.

“I think if we are ever going get to personalize medicine, we need to understand why the immune response is different in some people versus others,” she said.

COVID-19 has “beautifully illustrated” Zapata’s basic research question, making it more easily understood by people on the street, she said. The question is: why will one person have an overwhelming infection or sepsis in response to a microbe, while another person will have a mild infection?

A more grueling side of the pandemic for Zapata was outside the realm of her research. It was seeing what happened to undocumented people during a health crisis.

“With COVID, I saw them coming when they were already at death’s door–they were scared to come because they couldn’t pay for it—many were relieved to find that their hospital stays were covered by federal funding. They are not as lucky with other infections and conditions often presenting when the disease is severe.” Zapata said.

Their situation brought back memories of her own childhood when she was undocumented, and her family could not afford to pay for medicine, doctor’s visit, or hospital stays. Zapata was born in Nicaragua and was a war refugee as a child. Her family settled In the U.S. where she was undocumented until age 12. She said she hasn’t forgotten what that felt like.

This spring she spoke at a rally outside the state Capitol in favor of expanding Connecticut’s Medicaid program, known as HUSKY, to children 12 and younger, regardless of their immigration status. The legislature later approved the measure.

In addition to her advocacy work, Zapata has found other ways to de-stress.

“I was able to build a house in 2020 while this was all happening, and I was able to then plan and start a garden from scratch. And that has been so good for me,” she said. “What is it about gardening that just rejuvenates the soul? – perhaps we all need beauty in our lives?.”

Her property, she said, “was all dirt when I got here. I’ve been planting shrubs, planting beds. I'm starting a vegetable garden, so I have seedlings going,” she said. “I do my own landscaping, so I mowed the lawn yesterday. It's just fun. The peonies are about to bloom, the roses are starting to put on buds, and the irises are starting to open—it is all so lovely.

“When you're out there, just weeding and planting seeds, it's not adipose tissue or infections or COVID. I can turn that off for a moment,” she said.

The Infectious Diseases Section of the Department of Internal Medicine engages in a broad range of patient care, research, and educational activities. To learn more about their work, visit Infectious Diseases.

Submitted by Jane E. Dee on July 05, 2022