With the recent outbreak of measles in our country, we are faced with the real possibility of a vaccine preventable disease making its way into our every day lives, affecting patients, friends, family members, those we know and love. It’s time we realize that many diseases we Americans have comfortably taken for granted as having been eradicated in our country are potentially lurking as our herd immunity falls below protective rates.
WHAT IS HERD IMMUNITY?
When a critical portion of a community is immunized against a contagious disease, most members of the community are protected against that disease because there is little opportunity for an outbreak. Even those who are not eligible for certain vaccines—such as infants, pregnant women, or immunocompromised individuals—get some protection because the spread of contagious disease is contained. This is known as “community immunity.”
In the illustration below, the top box depicts a community in which no one is immunized and an outbreak occurs. In the middle box, some of the population is immunized but not enough to confer community immunity. In the bottom box, a critical portion of the population is immunized, protecting most community members.
This content is brought to you by: The National Institute of Allergy and Infectious Diseases (NIAID)
There are many in our country who, for whatever reason they may cite, have chosen to count on the protectiveness of herd immunity to keep their own children, whom they choose not to immunize, from getting these diseases. This is a disturbing phenomenon, because if not everyone is willing to contribute to herd immunity, its protectiveness will clearly wane, leaving many at risk. When the immunization rate falls below 95%, the risk of outbreak increases. Fear of these potentially deadly diseases such as measles, polio, pertussis, Haemophilus influenza meningitis, and others seems to be missing because the current generation of parents has not seen them up close and personal in their lifetimes. But most of your pediatricians have. We have seen the look of terror in the eyes of parents as we explain that their toddler will either die or live blind and deaf because of H. flu meningitis. Many of us in the field of pediatrics have seen children die of the measles. We have known friends, family members and loved ones either die of polio, or survive with lifelong disabilities because of it. These are real possibilities again in this country if we allow herd immunity to continue to fall. We as a nation owe it not only to our own children, but to the children in our schools, churches, daycares, across the street and around the corner. We owe it to every child to have the protection from diseases that we have the capability to prevent.
Nothing we do in medicine is completely without risk. Giving your child simple Tylenol or OTC cold medicines have risk. So, we cannot say to you that every vaccine is risk-free. There are known risks to each one, mainly fever and malaise. But when we compare the extremely low risk of a mild side effect such as that to the risk of your child getting a disease that is preventable, we consider it well worth it! Do we think the MMR is associated with autism in any way? Definitively not. The study that made the purported link between the two has been discredited, the physician has had his medical license stripped, and multiple large scientific studies have completely debunked any such association. But outspoken public figures who have taken up this issue and brought much attention to it have frightened the public unnecessarily. As you know, it is very difficult to “un-scare” people. We urge you to trust medical science and research, not the emotional outcry of individuals.
We encourage you to immunize your children. We believe it is not only safe, but the right thing to do. For your children as well as others. How can any one of us live with the possibility of putting someone else’s innocent child at risk because we have failed to protect our own?