Vaccinations: Why All the Controversy?

Controversy continues to swirl around vaccinations, despite scientific consensus that they are safe and effective. To sort the science from the news, an interdisciplinary group of experts from the Yale faculty held a discussion during the AYA Assembly, held on November 19.

There is a rigorous and robust scientific process to evaluate data before any changes are made to vaccine recommendations in this country, said Dr. Marietta Vazquez ’90, associate professor of general pediatrics and of nursing, who recently completed a rotation with the Centers for Disease Control and Prevention’s (CDC) Advisory Committee of Immunization Practices. That committee reviews mountains of data and listens to hundreds of people weigh in through public hearings. “It is heartbreaking to hear parents’ stories of children who have died from vaccine-preventable diseases,” said Vazquez.

Seventeen diseases are preventable through vaccines, and many of those vaccines are administered during early childhood. While the CDC sets the standard for recommendations, each state is responsible for overseeing public health. Enforcement comes as requirements to enroll in public schools and summer camps, and laws vary from state to state. In Connecticut, preschoolers are now required to be vaccinated for influenza, noted Linda Niccolai, an associate professor of epidemiology (microbial diseases). It has also become mandatory for healthcare workers.

The tensions, explained Dan Weinberger, assistant professor of epidemiology (microbial diseases), and Jason Schwartz, assistant professor of public health (health policy) and in the history of medicine, are between individual rights and protection of the greater and more vulnerable populations. Vaccines are a valued part of infection control practices for public health.

While relatively few small children are likely to die from influenza, many children have contact with people who may be immune-compromised, either through disease or age. These individuals are therefore far more vulnerable to potential complications from the flu.

Why should a two year old receive five or six shots in one doctor’s visit? Evidence shows that the immune system is robust enough to accept them all at once, and there are many practical advantages to such a delivery system. If vaccines are spaced out, the child is unprotected for a longer period, said Melinda Pettigrew, associate professor of epidemiology (microbial diseases). In addition, said Weinberger, there is a chance that the families won’t return and the kids won’t get the vaccines. It is barrier to ask a family to return for multiple times for these vaccines, added Schwartz, who pointed out that most families can’t afford extra visits and the time off from work to make them.

One issue with public confidence in vaccines is the mismatch between the flu vaccine, which is formulated based on models from the previous year. In some cases, vaccine makers miss the mark, and some patients who are vaccinated still get the flu. In the case of the HPV and shingles vaccines, it is not known yet how long the vaccines provide protection because they have not been around long enough.

Last year when a measles outbreak that originated in Disneyland made headlines the public debate became more polarized. When celebrities are spreading an anti-vaccine message it inflames a vocal minority, and we start to face suboptimal coverage, said Niccolai. “Without further polarizing the public, clinicians, who are the front lines, need to keep repeating the fact that vaccines are safe, effective, and recommended.”

In the case of the HPV vaccine for human papillomavirus, the controversy took an unfortunate turn when the vaccine first became available. Initially recommended for pre-adolescent girls, many parents denied the need to protect their soon-to-be adolescents from sexual activity. When Rick Perry, then governor of Texas, tried to mandate it, it turned out that one of his former staffers worked for the pharmaceutical company that produced the vaccine, creating even more backlash. In fact, HPV is the most common sexually transmitted disease, and over the course of a lifetime, 80 percent of people will get it. “This vaccine is really about preventing six kinds of cancer,” said Niccolai.