IDSA 2011: Vaccination Successes and Challenges, Part II

BOSTON, MA— In the first part of his lecture to the annual meeting of the Infectious Diseases Society of America, Larry Pickering, MD, senior advisor to the director of the National Center for Immunization and Respiratory Disease of the Centers for Disease Control and Prevention and professor of pediatrics at Emory University School of Medicine, described the success of the US immunization program in achieving very high rates of coverage. In the rest of the lecture, he went on to discuss the challenges the immunization program faces going forward. (To read our article on the first part of Pickering’s lecture, click here.)

The upshot of high immunization rates in the US is that we now have very low levels of vaccine-preventable diseases, Pickering explained, though in 2010 there were some outbreaks of pertussis (27,550 cases), mumps (2,612 cases), and measles (63 cases). One success he chose to highlight was the complete absence of rubella in 2010, and showed a picture of a rubella-stricken baby with bright-red skin and cloudy eyes.

In order to achieve herd protection (a phrase preferred by many in the infectious disease community to herd immunity), Pickering explained that both measles and pertussis require a 92-94% vaccine coverage rate. While nationwide vaccination rates for these diseases are at or close to this threshold, geographic pockets of vaccine resistance or deferral has caused vaccination rates to dip below the herd protection threshold in certain areas, leaving them vulnerable to outbreaks.

Along with the logistical and financial challenges of maintaining an immunization program, Pickering highlighted the ongoing problem of vaccine hesitancy fueled by misperceptions of vaccine safety and efficacy. He noted that a recent, exhaustive Institute of Medicine report on adverse vaccine effects found very low levels of adverse events, though in many instances there was not adequate evidence to prove or disprove a purported link between an adverse event and a vaccine, frequently because the events are so rare.

To point up the challenge of debunking misperceptions about adverse reactions and vaccines, Pickering referred to a Lancet study that estimated the number of coincident events that would occur after administering a hypothetical vaccine dose. For every 10 million people vaccinated, the study found, there would be 0.51 adverse events within one day of getting the vaccine, 3.58 within seven days, and 21.50 within six weeks. Projected over the entire US population, this translates into many adverse events that have nothing to do with vaccination, but are nonetheless often connected to it in people's minds.

After discussing the key role of health care providers in countering misperceptions about vaccines, Pickering directed the audience to several new technological tools for increasing adherence to the vaccine schedule: online schedulers developed by the CDC for children, adolescents, and adults, which will soon be available as mobile apps as well.

At the end of his lecture, Pickering screened a video illustrating the benefits of vaccination through a novel orchestration of Mozart’s “Eine Kleine Nachtmusik.” To check it out, click here.