Recently, several bloggers at The Parent Bloggers Network reviewed the new book by Paul Offit, MD, Vaccinated: One Man’s Quest to Defeat the World’s Deadliest Diseases. Not only did the book chronicle the vaccine development efforts of Maurice Hilleman — whom you may not recognize as being responsible for nine relatively recent vaccines — but it presented a well-researched and well-documented case for the public health implications of vaccines.
According to an April 2007 press release from the Centers for Disease Control and Prevention (CDC), "Every day, 11,000 babies are born in the United States who will need to be immunized against 14 diseases before age two. Despite recent gains in infant immunization coverage, more than 20 percent of the nation’s two-year-olds are still not fully immunized against infectious diseases to which they are especially vulnerable." To clarify, infants and toddlers are not "especially vulnerable" because these diseases are prevalent, but because the very young, the very old, and the immunocompromised (i.e., those who are already weakened by disease) are more likely to contract any contagious disease to which they are exposed.
However, the reason that diseases such as measles, mumps, and polio — among many others — are no longer prevalent is that vaccines were developed and are included in a standard schedule of immunizations given to infants and toddlers in the United States and other Western nations. A CDC article titled "What Would Happen If We Stopped Vaccinations" included the following facts:
- Before polio vaccine was available, 13,000 to 20,000 cases of paralytic polio were reported each year in the United States.
- Before measles immunization was available, nearly everyone in the U.S. got measles.
- Before Hib vaccine became available, Hib was the most common cause of bacterial meningitis in U.S. infants and children. Before the vaccine was developed, there were approximately 20,000 invasive Hib cases annually.
- Before pertussis immunizations were available, nearly all children developed whooping cough. In the U.S., prior to pertussis immunization, between 150,000 and 260,000 cases of pertussis were reported each year, with up to 9,000 pertussis-related deaths.
- Before pneumococcal conjugate vaccine became available for children, pneumococcus caused 63,000 cases of invasive pneumococcal disease and 6,100 deaths in the U.S. each year.
- Up to 90 percent of infants born to mothers infected with rubella during the first trimester of pregnancy will develop congenital rubella syndrome (CRS), resulting in heart defects, cataracts, mental retardation, and deafness. In 1964-1965, before rubella immunization was used routinely in the U.S., there was an epidemic of rubella that resulted in an estimated 20,000 infants born with CRS, with 2,100 neonatal deaths and 11,250 miscarriages. Of the 20,000 infants born with CRS, 11,600 were deaf, 3,580 were blind, and 1,800 were mentally retarded.
- Before the mumps vaccine was introduced, mumps was a major cause of deafness in children, occurring in approximately 1 in 20,000 reported cases.
Almost all of us received most of these vaccines as children. Some — such as pneumococcal (licensed in 1977) and Hib (licensed in 1987) — weren’t even on the schedule yet. But we never witnessed the polio scares of the 1940s and 1950s. Whooping cough was unknown. When we got pregnant, we didn’t even think about the possible effects of rubella on our unborn children.
These once common diseases are now rarely seen, thanks to the standard immunization schedule which results in a phenomenon known as "herd immunity." Per a National Institutes of Health (NIH) publication titled "Understanding Vaccines", "if a critical number of people in a community are vaccinated against a particular illness, the entire group becomes less likely to get the disease." This herd immunity is what protects those children who have not been vaccinated.
But more parents are opting not to vaccinate their children, citing moral objections and disagreement with the supposed public health risks of abstaining. In fact, they maintain that it is riskier to vaccinate than not to, implicating vaccine ingredients such as thimerosal and mercury in asthma and other childhood diseases.
While it seems that abstinence from vaccinations would be a personal decision on the part of parents, definite public health implications exist. Again, from the NIH:
"If enough people in a community forego vaccinations, diseases can reappear. In 1974, the Japanese government stopped vaccinating against pertussis because of public concern about the vaccine’s safety and because no one had died from the disease the previous year. Five years later, a pertussis epidemic in Japan sickened 13,000 people and killed 41."
Perhaps more convincing than the statistics cited above is the Global Immunization Vision and Strategy for 2006-2015, as set forth by the World Health Organization. "Its chief goal is to, by 2015 or earlier, reduce illness and death due to vaccine-preventable diseases by at least two thirds compared to 2000 levels." While other public health factors such as sanitation play a more significant role in disease control and prevention in non-Western nations than in Western nations, the worldwide impact of vaccines is undeniable.
When your pediatrician advises you to follow the standard immunization schedule, that guidance is not the opinion of a single doctor. It’s not a third-hand inconclusive personal anecdote. It’s not an unsubstantiated quote from a parenting website. It’s the collective conclusion of thousands of doctors and medical researchers from around the world who are dedicated to caring for people and saving lives.
And you can choose — for whatever reason (and many people have many good reasons) — not to follow the advice of your pediatrician. But it’s a fact that most of us who do adhere to the immunization schedule is what affords those who don’t that herd immunity, that relative safety from these once-common diseases.