(CNN) Dr. Deborah Birx can be seen at the White House briefing room lectern most days in her new role as what Vice President Mike Pence calls his " right arm " on the coronavirus task force, making her one of the most visible medical officials in the country.

But in 2003, Birx, an HIV researcher, was trying to get the attention of the official helming the global AIDS response -- by standing outside of his house for a week.

Birx was the director of the US Military HIV Research Program at the Walter Reed Army Institute of Research and intrigued by then-President George W. Bush's new President's Emergency Plan for AIDS Relief, or PEPFAR -- an unprecedented, $3 billion-a-year program to help the world fight AIDS.

"As soon as President Bush announced PEPFAR at the State of the Union, I had already been working in Africa for about five or six years" doing HIV vaccine research, Birx said on the George W. Bush Presidential Center's podcast in September.

"So when President Bush announced this, I flew back from Kenya and waited outside of (then-Director of the Office of National AIDS Policy) Joe O'Neill's townhouse for almost a week in February to get a meeting with him," she added.

Birx went in with a Powerpoint presentation of "180 slides, and until he agreed to let us be part, to let the Army also be part of PEPFAR, I was not leaving his office, and so I wore him down."

That anecdote highlights the determination and passion for studying infectious diseases that have been key touchstones in Birx's life. Birx's husband had an Army scholarship and pursued his residency at the Walter Reed National Military Medical Center, so she joined the military to pursue an internal medicine residency there with him, she said on the podcast.

In 2014, then-President Barack Obama nominated Birx to her current role at the State Department as an ambassador-at-large and coordinator of the US Government Activities to Combat HIV/AIDS and US Special Representative for Global Health Diplomacy. She has lead the implementation of global PEPFAR programs, which has saved 17 million lives and prevented millions of HIV infection cases, according to a 2019 State Department report

Birx told the Center for Strategic and International Studies on a podcast that aired in February -- just before she was appointed to the coronavirus task force -- that when assessing some of PEPFAR's health initiatives, "many people tell us that these things aren't possible."

"I've been privileged to work on the continent for a long time -- I don't find anything impossible," she continued, adding that "it may not be yes today, but we eventually get to yes ... it's the spirit of the program."

Despite her ties to the Obama administration, Birx was able to develop a close relationship with the Trump White House, according to a source familiar with her situation, in part because Trump campaign official Matt Mowers served as her chief of staff for nearly two years.

She has overhauled the HIV strategy for the Trump administration, and she and Pence developed a relationship in 2018 when she spoke at the World AIDS Day event at the White House. Birx did not ask for this job -- the White House came to her, sources said.

Now that she is on the coronavirus task force, Birx has moved into a West Wing office space, White House spokesperson Katie Miller confirmed to CNN.

She has taken on the herculean effort of urging millennials to follow CDC guidance on social distancing. On Wednesday, she expressed concern that millennials may be at a higher risk of getting seriously ill from coronavirus than initially thought, and earlier in the week she referenced her status as mother to two millennials -- daughters Danielle and Devynn.

"I want to speak particularly to our largest generation now, our millennials," Birx said Monday. "I (am) the mom of two wonderful millennial young women who are bright and hardworking and I will tell you what I told to them -- they are the core group that will stop this virus."

That was not the first time that Birx's daughters had a brush with her work, which in one case likely spared them both from a serious health risk.

In then-Secretary of State John Kerry's remarks at her swearing-in for her ambassadorship, he told a story of how during the birth of her oldest daughter in 1983, Birx suffered serious blood loss. A blood transfusion was ordered, but she had read a report about a new, largely unknown disease that made blood transfusions risky.

"And literally, just before she passed out from pain, Debbie screamed, 'Do not let them give me blood,'" Kerry said. "Her husband refused the transfusion, and it is a mighty good thing that he did. Because the hospital learned later that the blood of her blood type that they would have used was contaminated with HIV."

"That was Debbie's first brush with AIDS, and it literally changed her," he continued. "It made her think hard not just about the perils of this new disease, but about her responsibility to fight it."

Birx seemed to confirm the story in her acceptance remarks afterward.

"I have no idea how he got that story," she said, adding with a laugh that "he's got good intel."