In the weeks following 9/11, another attack gripped the U.S. after letters containing dangerous anthrax spores were delivered to the offices of several news media organizations and two sitting U.S. senators. 

The act of bioterrorism, also known by its FBI case name “Amerithrax,” killed five people, infected 43 in total, and spurred an investigation that FBI officials later called “one of the largest and most complex in the history of law enforcement.”

RTI infectious disease epidemiologist Pia MacDonald, PhD, MPH, CPH, found herself in the middle of it all as an Epidemic Intelligence Service officer with the US Centers for Disease Control and Prevention (CDC).

MacDonald had already been temporarily relocated to New York City to review symptoms of people who visited emergency departments following the collapse of the World Trade Centers, and when reports of potential anthrax cases emerged, she had to pivot at a moment’s notice.

“I remember being sent to NBC headquarters to provide educational sessions for employees about anthrax and what symptoms to look for,” MacDonald says. “I felt very much a part of the national response to those events in 2001.”

It is one of many memories that stands out to MacDonald, who has a lot to choose from. Her distinguished career in domestic and international public health and epidemiological research so far has spanned 25 years.

Photo: Switchpoint 2018

A Natural Scientist 

The fact that MacDonald has dedicated her professional life to science is not necessarily a surprise. As she tells it, the scientific method — forming a hypothesis, testing it, and drawing interpretations — has always been more of an instinct than a learned skill.  

“From the beginning, I’ve had an insatiable curiosity and I think I’ve just had a personality that looks at the world through a science lens and with a scientific discipline,” she says. “One of my favorite ‘toys’ as a young child was a microscope and chemistry set.”

MacDonald’s love of epidemiology came into focus a bit later. 

During her undergraduate science studies at the University of California, Berkeley, she was fascinated by a course that examined trends in infectious diseases over the course of human history, from the bubonic plague to the AIDS epidemic. It led her to spend two years in Thailand in the Peace Corps post-graduation, though upon returning home, she was still searching for her path. She figured she might be suited for a career in medical geography. 

Shortly thereafter, when she was visiting graduate programs, everything clicked. She sat in on an epidemiology class and realized it was a perfect match for her interest in the intersection of disease, environment, and people. 

Chasing infectious diseases across the globe also offered an opportunity to see the world, which added to the appeal.

Photo: Chris Polydoroff

Responding to Ebola in West Africa

After time as an Epidemic Intelligence Service officer at the CDC, which included her stint in New York City and many other response efforts to acute public health events, MacDonald was recruited to the Epidemiology Department at the UNC Gillings School of Global Public Health. She went on to spend a decade as a faculty member at Gillings before eventually settling at RTI.

“Literally the day I arrived at RTI, my colleagues said, ‘Hey, we talked about you over the weekend, here is a request for applications with a one-week turnaround that might be interesting.’ And I looked at it and it was related to the Ebola response in West Africa,” MacDonald recalls. “It was daunting to arrive at a new job and immediately begin discussing work in a place I had never been. But I knew I could not pass up the chance to try.”

MacDonald and her team scrambled to put together an application for the work, which involved serving as an on-the-ground implementing partner funded by the CDC to support the national government in Guinea in responding to the Ebola outbreak and helping reconstruct the region’s public health infrastructure in the outbreak’s aftermath. A few months later, they were notified their application had been selected and MacDonald would be the lead investigator. 

Before they knew it, MacDonald and her RTI colleagues were in Guinea — the epicenter of the outbreak — where their work focused on supporting the ongoing public health response: integrating data, training responders on Ebola contact tracing, setting up screening areas that would triage Ebola patients, and much more.

“The infrastructure building afterward was very much focused on the prevent, detect, respond paradigm for global health security, where you’re building up your system to detect outbreaks faster and make sure they get reported and responded to before they get very large or expand to other countries,” MacDonald says. 

The work paid off. MacDonald points to Guinea’s swift response to the threat of another Ebola outbreak in early 2021. They were able to detect cases early and limit spread — a textbook response to a deadly disease.

A (Hopefully) Once-in-a-Lifetime Crisis

Few people or countries were prepared for the emergence of coronavirus, also known as SARS-CoV-2 — though MacDonald proudly notes Guinea’s national government was ahead of the curve on that one, too, having commenced preparations months before it took hold globally.

“I remember thinking we were headed for a once-in-a-lifetime global public health crisis,” MacDonald says. “SARS-CoV-2 was a new, highly contagious pathogen that caused a disease we had no experience treating, and for which we had no vaccine. When you put all that together, you realize there’s a big storm coming. With all the naysayers early on, I kept asking myself, ‘Am I overreacting?’”

Amid the pandemic, MacDonald has pivoted, as she has become accustomed to doing across her time in public health and epidemiology. 

She has worked with the state of Louisiana on contact-tracing efforts and supported work to model the spread of COVID-19 in North Carolina. She has also played an integral role in the development of a COVID-19 epidemiological data insights tool designed to help federal, state, and local public health officials and key stakeholders make informed decisions on how to prioritize response efforts, including contact tracing, placement of testing sites, and vaccine distribution.

MacDonald has also shared her expertise with community groups, teachers, high school and college students, lawyers, and local and national media during the pandemic to help keep the public abreast of the latest guidance and epidemiological research.

With an undoubtedly busy schedule, she still finds time to ponder the future of public health, where she hopes to “revolutionize” public health surveillance, and mentor women in science to become more visible and recognized for their contributions.

“Investment in public health surveillance has languished for many years. It needs a complete overhaul and modernization immediately and for the future. We need to leverage enormous advances in data science and analytics, machine learning, and genomic sequencing, at a minimum,” MacDonald says.

As for supporting other women, MacDonald says making time to be a mentor to other women in the field is a priority because it is something she had little of as an aspiring scientist. Naturally, she is attacking it like a response to an infectious disease: using data, detecting the issues and responding, with the hope of building a stronger, more inclusive future.