Dec 10, 2020
The New CDC Director’s Most Compelling Pandemic Ideas
Rochelle Walensky has a legacy of forward-thinking ideas for pandemic control
In pandemics prior to the ongoing Covid-19 crisis, the U.S. Centers for Disease Control and Prevention (CDC) was front and center. The agency’s leaders and scientists led weekly — sometimes daily — press conferences during the Ebola outbreak and tracked the spread of the mosquitoes that transmit Zika. During the Covid-19 pandemic, however, the agency has been shockingly slow to issue science-backed recommendations on preventing infections and has been cut out of hospital surveillance. CDC officers are rarely ever heard from, including the head of the agency Robert Redfield, MD, who seems to only speak when compelled by Congress.
That’s why all eyes are on President-elect Joe Biden’s choice for CDC director this week. On Monday his team selected Rochelle Walensky, MD, MPH, head of infectious diseases at Massachusetts General Hospital, for the role. The response from the public health and infectious disease community has been positive.
“It’s great that President-elect Biden is moving fast to form his health team,” says Tom Frieden, MD, president and CEO of Resolve to Save Lives, an initiative of the public health nonprofit Vital Strategies, who led the CDC under former president Barack Obama. “We’re in the midst of the most disruptive global pandemic in a century, with cases escalating in the United States and continued absence of organization and leadership from the White House. We look forward to having a strong, science-based, effectively organized federal team to lead the response and vaccine rollout.”
Walensky, like Redfield, is an HIV researcher and clinician. She doesn’t have experience with respiratory viruses like Covid-19 per se, but her research work during the pandemic indicates that she has the kind of mindset and experience making decisions based on modeling that will be critical for navigating the pandemic.
“Her views on testing, data on therapeutics, vaccine science, and public health messaging are all note-perfect,” says Jeremy Faust, MD, MS, an emergency medicine expert and instructor at Brigham and Women’s Hospital who began collaborating with Walensky on research during the pandemic.
“She is not shy about her own knowledge and expertise, but she also knows when to respect the expertise of others — i.e. to trust her team and work collaboratively,” he adds. “When we were really in the thick of it, I realized that she was both collaborating with me and mentoring me. She did not have to do that. That reflects my sense of who she is.”
Walensky’s research work on HIV/AIDS is focused on model-based analysis for decision-making and figuring out the framework to make complex decisions around the cost-effectiveness of testing, care, and prevention strategies. Her work has informed both clinical trial designs and health policies.
This approach makes Walensky an expert on decision-making in imperfect situations, and how to use science to make tough calls and priorities. During the pandemic, Walensky has teamed up with A. David Paltiel, PhD, a professor of health policy and management at Yale School of Public Health, on multiple studies that look at better solutions for the Covid-19 response. In September the duo argued in the journal Health Affairs that saliva-based antigen testing is actually better than PCR swabs when it comes to preventing SARS-CoV-2 outbreaks. While antigen tests have been given a bad rap for having less diagnostic accuracy than PCR, their value is highly underestimated, they wrote:
When you go to the grocery store, eat in a restaurant or play pick-up basketball, the person you are trying to avoid is the person who might transmit the virus to you during that activity. While all spreaders are infected with the SARS-CoV-2 virus, not all persons infected with SARS-CoV-2 are spreaders. Not everyone who has detectable levels of SARS-CoV-2 virus in their airways is shedding virus in sufficient quantity to pose a transmission risk to others. When it comes to preventing the spread of the virus and containing outbreaks, it’s the infectious people you want to identify and isolate….
…Testing to confirm that you pose no risk of inadvertent transmission is called “surveillance testing.” It serves a critical function in containing outbreaks, especially since the other tools at our disposal for this purpose (e.g., masks, hand-washing, social distancing, and quarantine) are all limited in number, adherence, and effectiveness.
When evaluating whether a test for SARS-CoV-2 is up to the task, the first things we need to do is to specify carefully what exactly that task is: Because it turns out that the PCR-based nasal swab your caregiver uses in the hospital does a great job determining if you are infected but it does a rotten job of zooming in on whether you are infectious. By contrast, the rapid saliva-based antigen test with the 30 percent false negative rate does a poor job of diagnosing infection, but it is likely the better tool for judging infectiousness.
In another Health Affairs piece published in November, Walensky and her co-authors used a mathematical simulation of vaccination and found that factors related to implementation are more important to the success of vaccination programs than a vaccine’s efficacy in clinical trials. “The benefits of a vaccine will decline substantially in the event of manufacturing or deployment delays, significant vaccine hesitancy, or greater epidemic severity,” they wrote. “Our findings demonstrate the urgent need for health officials to invest greater financial resources and attention to vaccine production and distribution programs, to redouble efforts to promote public confidence in Covid-19 vaccines, and to encourage continued adherence to other mitigation approaches, even after a vaccine becomes available.”
In another paper published in the journal JAMA, Walensky even assessed SARS-CoV-2 screening strategies that would allow for colleges to reopen. She conducted an analytic modeling study of a hypothetical group of nearly 5,000 college-age students without Covid-19 and 10 students with undetected asymptomatic cases of the virus. Walensky and her co-authors’ findings suggested that testing all students every two days with screening measures like antigen tests would likely be needed in addition to making sure students have places to isolate.
While Walensky has long been a prolific researcher, her work on Covid-19 suggests that she is well-equipped to use science and modeling to help identify the best strategies for navigating the pandemic. It also suggests she’s a solutions-oriented leader that would make the case for embracing solutions like using less accurate tests to ensure a lower likelihood of transmission on a large scale. It’s that kind of innovative thinking — along with her media savvy (she is frequently speaking to the press) — that will make her a compelling leader for the CDC.
“We keep saying ‘follow the science,’” says Faust. “Dr. Walensky is all about that. If she has an opinion, and new data emerges that contradicts it, she’ll change her opinion. I’ve seen that happen. We experienced it together when we were staring at data we did not expect. That’s what experts do; they change their opinions in response to the facts, not the opposite.”
