Anne Schuchat, MD, provides some history and insights on CDC’s role in safeguarding public health when the microbial world collides with the human world.
Anne Schuchat, MD
In the Keynote address of the ASM Microbe 2018 meeting, Anne Schuchat, MD, Principal Deputy Director, US Centers for Disease Control and Prevention (CDC), Atlanta, Georgia, provided some history and insights on CDC’s role in safeguarding public health when the microbial world collides with the human world.
The themes that ran through her talk delivered on June 9 were the virtues of remaining humble when it comes to dealing with bacteria and in learning from adversity and failure. She is familiar with both during her time at CDC.
Humility is necessary when facing the microbial world. With advances in knowledge and technology, one can fall into the trap of feeling in control. But microorganisms have been around eons longer than us and have learned to adapt or die. “Microbes literally live their lives in log phase. They are always adapting and always adjusting,” said Dr. Schuchat.
In dealing with the moving target of microorganisms, accepting that failures will occur is a must. What comes next is crucial. Failure in an infection control effort, such as occurred during the first outbreak of Legionnaire’s disease in 1976 during an American Legion convention in Philadelphia, Pennsylvania, can be devastating. Or, as happened as the CDC faced withering public criticism over their response to the outbreak, the failure can galvanize institutional efforts to hunker down and solve the problem.
Even with resolve, knowledge, and prevention strategies in place, problems can arise. The result, exemplified by influenza, can be a loss of control over a situation where microbial control was presumed. Influenza control efforts have been ongoing for a century. And yet, CDC surveillance data showed that the 2017-2018 influenza season was the highest in terms of influenza-related hospital admission since data collection began. That was a humbling and disturbing year for CDC.
The H3N2 influenza virus has changed its structure over the past 50 years with increased glycosylation of surface antigens. This has made it tougher to mount effective vaccines. Influenza viruses are adept at testing the water, with antigenic changes that favor spread of infection being retained and changes that are not quickly discarded. A recent series of outbreaks of influenza in Asia caused by the H7N9 virus is a sobering example. The initial few waves of the infection gave way to fewer cases and the sense that some control had been restored. Then a fifth wave of infection dwarfed the others in terms of case numbers.
“Influenza pandemics are coming. How we prepare is crucial,” said Dr. Schuchat. One avenue of preparation that CDC has adopted is a containment strategy for infections. “Public health teams nationwide can launch early, aggressive responses to contain spread and protect people at the first sign of antibiotic resistance, every time,” she said.
In addition to the containment strategy, CDC is working with other federal agencies to combat antibiotic resistance nationwide by preventing infections and improving antibiotic use, although Dr. Schuchat admitted that antibiotic stewardship still faces challenges in 2018 because of the resistance of some to practice-changing ways.
A world of mobility creates another challenge. As the outbreak of severe acute respiratory syndrome (SARS) in Toronto, Canada—beginning in February 2003—devastatingly showed, microbial problems can be just a plane ride away. The global spread of a disease within a few days is not just conceivable, it is a reality. But mobility is also a neighborhood issue. In communities, patient movement between health care facilities can spread infections. A coordinated system of disease surveillance and response between health care facilities is an important roadblock to outbreaks.
Vaccination is one stalwart solution to infectious diseases. But a problem comes from infections that have been historically sporadic. The capacity to develop and manufacture vaccines is beyond the scope of governments. Industrial involvement is needed. However, getting industries on-board to manufacture vaccines for a potential microbial problem that may not arise is daunting. “Market forces are not enough of an incentive for vaccine development,” said Dr. Schuchat.
A success story in infection control has been CDC’s advanced molecular detection (AMD) program. An AMD pillar is gene sequencing, especially the technique of next-generation sequencing. The early days of next-generation sequencing in public health were problematic, given the necessary monetary investment and need to upgrade staff expertise. These roadblocks have been cleared and the technique is now showing its public health ‘oomph’ in, as just 1 example, the tracking of tuberculosis infections.
The technique of pulsed-field gel electrophoresis in the form of a surveillance program dubbed PulseNet has revolutionized the detection and identification of foodborne microbial pathogens. Electrophoretic patterns can be analogous to a fingerprint, which can allow an infection to be backtracked to its source. Furthermore, the analysis of an outbreak can help clarify how and why the outbreak started, which can help put steps in place to minimize a repeat performance.
A space-age sounding technology termed matrix-assisted laser desorption ionization—time of flight mass spectrometry, in which the pattern of ions formed by an energized sample provides another fingerprint that identifies the sample—enables the rapid and accurate identification of pathogens, especially ones that are rarely encountered.
The advances in technology and implementation of safeguard strategies continue at CDC. Some pride in the accomplishments achieved is understandable and warranted. But, the past must remain top-of-mind, cautioned Dr. Shuchat.
“Mistakes occur in public health. Mistakes are painful. They can be embarrassing but they can also be motivating. We must keep learning from our mistakes. To not do so is to let public health lag. The perpetual challenge of influenza reminds us of the importance of public health.”
SATURDAY Keynote Presentation
Living in (and Learning from) a Microbial World
Anne Schuchat, MD, Principal Deputy Director, Centers for Disease Control & Prevention, Atlanta, Georgia
Brian Hoyle, PhD, is a medical and science writer and editor from Halifax, Nova Scotia, Canada. He has been a full-time freelance writer/editor for over 15 years. Prior to that, he was a research microbiologist and lab manager of a provincial government water testing lab. He can be reached at email@example.com.