The new normal: Infection threats keep on coming

Complacency is the enemy of health protection’

Crisis response mode and rapidly emerging infections are the new normal for a public health system that has to expect new threats as part of the daily job, warned Julie Gerberding, MD, MPH, director of the Centers for Disease Control and Prevention (CDC).

Recounting the plethora of plagues that have beset the country over the last few years — anthrax attacks, West Nile virus, severe acute respiratory syndrome (SARS), and monkeypox — Gerberding said expect more of the same.

"It’s been a very extraordinary period for infectious diseases and emerging problems," she told some 1,700 attendees recently in Atlanta at the annual Conference on Emerging Infectious Diseases. "There are so many times that we look on this period and think, Please, could we get back to the good old days?’ My message today is that the good old days are gone. This is the new normal."

SARS, for example, presumably began with an occupational infection — the physician who was the index case in the outbreak among travelers at a Hong Kong hotel. As the newly infected departed to the various corners of the world, the disease emerged globally "virtually overnight," she said. "This pattern of global problems becoming local and local problems very quickly becoming global has been repeated over and over again the past several years," Gerberding added.

Similarly, we now know that prairie dogs are particularly vulnerable to monkeypox and very efficient amplifiers of the disease from other zoonotic sources to humans. As that outbreak last year showed, "a problem that seems to be remote over in one part of the world suddenly becomes a problem in our backyard," she said. "We are really all contending with infection threats wherever they emerge. We are living in an incredibly small world."

Complacency the major challenge

Delivering the keynote address at the conference, Gerberding outlined five challenges to meeting the threat of emerging infections. The greatest threat is complacency, a lapse from the new normal into old ways of thinking, she explained. To deal with internal complacency the CDC is continuously re-examining its mission under a program called the Futures Initiative.

The program is designed in part to enable the CDC to be as effective as it can be in the critical lull period after one threat dies down and before the next wave rises. Looking at a sparsely dotted map of smallpox immunizations in the United States, Gerberding acknowledged the obvious. "It is very difficult for people to sustain the belief that there is a smallpox threat. We don’t know how big the threat is, but I can tell you right now it is not zero."

States that went through the controversial immunization program have found subsequent benefits in the relationships and clinical partnerships formed. "When I visited Pennsylvania this year at the height of the hepatitis A virus outbreak at a restaurant, the first thing the health offices spontaneously said was, Thank goodness we have been working on the smallpox plan because we could deliver the hepatitis A vaccine to people over a weekend. We were prepared to do that.’"

The inevitably of another influenza pandemic is certainly a tonic against complacency. As flu threats arise and dissipate every few years, experts have continually warned that the much discussed scenario will happen eventually — an antigenic shift resulting in a highly infectious strain with the distinct possibility of no immediate vaccine.

"Who in their right mind would imagine that this is not going to happen," she said. "These viruses are constantly evolving. How many times do we have to see a pandemic before we come to grips with the fact that that’s what this virus does. Our tendency to not believe it until we see it is a profound interference in our capacity to truly be prepared. I am so pleased with the steps that are being taken to accept the threat of influenza and get busy on how we are finally going to [accomplish] pandemic influenza preparedness. Complacency is the enemy of health protection."

Four other challenges

Gerberding outlined four other major challenges posed by emerging infections, which are summarized as follows:

  • Cognition: "By cognition, I mean threat detection and the scientific capability to identify the nature of the threat and to initiate the appropriate evidence-based response," she said. A key to recognizing emerging threats is the astute clinician that alerts authorities of the first cases or an unusual cluster. Such was the case when a clinician in Vietnam saw that SARS had a high attack rate among health care workers treating infected patients, a finding that confirmed the severity of the outbreak and prompted the CDC to activate its emergency response center. "In my work as a hospital epidemiologist, never did I see a disease that had an attack rate among health care workers of 56%," Gerberding said. "It’s not so much the ability to detect a new problem. It is also connecting the dots — recognizing that a problem in the animal kingdom could be very easily be a problem in human health."
  • Containment: Once an emerging infection has been recognized, it must be contained through isolation of infected patients and quarantine of those exposed but not yet ill. The personal and social disruption implied by "quarantine" makes it a powerful public health word. "I remember at CDC we worried for quite a while about when we would begin to use the quarantine’ word in our communications," Gerberding said. "But what we have been able to accomplish now is bringing the word out into the open as one of two major platforms for containment. This is a very old-fashioned way of containing threats, but it works." As SARS showed, delayed patient isolation can easily translate into secondary cases. "This is common sense, but it does illustrate how quickly isolation must proceed if it is going to be successful," she says.

    During the SARS outbreak last year, 2.7 million airline passengers were alerted about the disease "not because we at that time appreciated that airlines per se were a threat, but because that was how people were returning from parts of the [world] where transmission was ongoing," she said. However, investigators have since determined that transmission actually occurred on airplanes as SARS patients left stricken areas. "It certainly increases the challenge of containment when we have to not only [advise them] to seek medical attention when they return, but we have to be concerned about containment and isolation while they are in route," Gerberding continued.

  • Countermeasures: "By countermeasures, I mean the vaccines, the antimicrobials the products use to mitigate the human consequences," she said. These agents must be available, delivered in a timely fashion, and be effective and safe. At one point during the anthrax attacks, for example, 30,000 people were advised to at least start antibiotics. "It wouldn’t take too much imagination to think about scaling up the nature of that threat so that we really would be in a position where it would be necessary to deliver antimicrobial therapy or vaccine to hundreds of thousands of people potentially exposed to anthrax in a very short period of time. This was a wake-up call."

    Even with nonpandemic seasonal flu strains, the creation of annual vaccine is a fairly dramatic race against time. "We may know the strain that is most likely to be present in the next year’s flu outbreak sometime in February and March, and we have only really a four-month window to get that strain into reassortment, seed vaccine and get it into production, test the potency, and get it packaged and distributed in time to vaccinate people," she added. "It’s sobering to recognize how far we have to go to have complete countermeasure protection for all of the threats we know about, let alone the threats that are yet to emerge."

  • Communication: To be an effective risk communicator, you need to be first with the information, right with the information, and credible so people trust your message, she said. "It is not always possibly to do those three things simultaneously, so you have to make some real hard choices about which ones your going to prioritize," Gerberding said. "At CDC, we have made the conscious decision that we are going to tell the truth and that our credibility is the most important component of communication. The lesson for me personally is that whenever there is a problem I try to think, who are the people who will need this information?"