The Consequences of Declining Childhood Vaccination

ACCORDING TO THE Centers for Disease Control and Prevention (CDC), 20 percent of the nation’s 2-year-olds are missing one or more recommended vaccinations,¹ and vaccination rates for kindergarteners are low enough in some areas to put communities at risk of losing community immunity.² Medical experts say the community immunity threshold, the proportion of the population that must be immunized to prevent diseases from spreading, is considered to be 95 percent. Once immunization rates fall below this level, diseases start to return and transmission rates dramatically increase, which can result in outbreaks and epidemics. So, why are childhood vaccination rates decreasing, and what can be done to prevent it?

Ensuring Vaccines’ Safety

The U.S. Food and Drug Administration (FDA) approves and regulates all vaccines in the United States to ensure their safety, purity, potency and effectiveness. Before a vaccine is approved by FDA, results of studies on safety and efficacy are evaluated by highly trained FDA scientists and doctors. According to FDA, “Like any medicine, vaccines have benefits and risks, and although highly effective, no vaccine is 100 percent effective in preventing disease or 100 percent safe in all individuals. Most side effects of vaccines are usually minor and short-lived. For example, a person may feel soreness at the injection site or experience a mild fever. Serious vaccine reactions are extremely rare, but they can happen.”³

“The United States’ long-standing vaccine safety system ensures that vaccines are as safe as possible,” says the Immunization Action Coalition. “In fact, currently, the United States has the safest, most effective vaccine supply in its history.”4 CDC’s current immunization schedule lists 14 diseases for which vaccinations are recommended for babies and young children, including hepatitis B; rotavirus; diphtheria, tetanus, and acellular pertussis; Haemophilus influenzae type b; pneumococcal conjugate; inactivated poliovirus; influenza; measles, mumps, rubella (MMR); varicella (VAR); and hepatitis A.⁵

More Parents Opting Out

According to a CDC report, more parents are opting out of having their children vaccinated in certain communities, with the median rate for nonmedical vaccination exemptions as high as 7 percent in Oregon.²

Three waivers allow parents to exempt their children from vaccinations. The first is a medical exemption for children who are severely allergic to a vaccine component; children who have an acute illness (this is only temporary until the child is well again); children who have compromised immune systems; and babies who are too young for their first immunization (younger than 2 months old). The second is a philosophical exemption for parents who do not believe in immunization due to personal beliefs. And, the third is a religious exemption for parents who refuse immunization due to religious reasons.⁶ To curb increasing exemption rates, three states — California, West Virginia and Mississippi — have passed bills to eliminate religious and personal exemptions for vaccinations.⁷

The 2016 National Immunization Survey-Child (NIS-Child), which includes data on 14,988 children aged 19 to 35 months, also suggests childhood vaccination rates are declining, with vaccine/dose rates lower in 2016 compared to 2015, except for the first and second doses of hepatitis A and rotavirus.⁸ According to the survey’s report, “For most vaccines, coverage was lower among black children, children living below the federal poverty level, and children who were uninsured or covered by Medicaid compared with white children, children living at or above the federal poverty level, and children with private insurance. Coverage with recommended vaccines for children aged 19-35 months continues to be high and stable but remains below 90 percent for vaccines that require booster doses during the second year of life and for other recommended vaccines.”⁸

And, while vaccines have been scientifically proven safe, the NIS-Child data show parents who choose to either delay vaccinating their children in accordance with CDC’s immunization schedule, or not to vaccinate their children at all, has been gaining ground.

Common Parental Vaccine Concerns

According to the American Academy of Pediatrics (APA), parents have expressed several concerns about vaccinating their children:

1. Too many/too soon. Parents worry giving too many vaccines too soon may overwhelm a baby’s immune system. But, APA states that although infants do receive a lot of vaccines, they are given at the time babies are most at risk of illness and serious complications from the disease. And, vaccines are well-studied to ensure they are safe to give all at once. In addition, although children receive more vaccines today than they did in the past, the number of antigens is fewer.

2. Nonstandard schedules. Some parents would prefer to spread out the timing of vaccines and believe an alternative or nonstandard schedule is safer. But, APA states the recommended schedule is designed to protect children when they are most vulnerable to the diseases vaccines prevent.

3. Vaccine ingredients. Parents worry about vaccines’ ingredients, including antigens, adjuvants, aluminum and thimerosal. But, according to APA:

• Antigens stimulate the body’s immune response to make antibodies (cells that protect against infection). Antigens in vaccines cause the immune system to make antibodies that will protect the body if it comes into contact with a bacteria or virus that can cause illnesses.
• Adjuvants help increase the body’s immune response to the antigen in the vaccine. Adjuvants make it possible to use smaller amounts of antigens and decrease the number of doses needed.
• Aluminum salts or gels have been used safely in vaccines for more than 70 years. The amount of aluminum in vaccines is similar to that found in a 33-ounce can of infant formula.
• Thimerosal is a mercury-based preservative that has been used to prevent contamination of vaccines with bacteria and fungi. Most childhood vaccines do not contain thimerosal, with two exceptions: the manufacturing process and multi-dose vials. Many studies have shown no link between thimerosal and autism. In fact, rates of autism have actually increased since thimerosal was removed from vaccines in 2001.

4. Autism. Some parents correlate the relationship of vaccines and autism. In 1998, The Lancet published an article by Andrew Wakefield, MD, and colleagues, that reported on a study of eight children who reportedly developed autism after receiving the MMR vaccine. In 2010, The Lancet retracted the study, citing ethical misconduct on the part of Dr. Wakefield. And, over the past decade, 10 of the 13 authors of that article have retracted the findings. Since then, scientific studies comparing thousands of children who have and have not received the vaccine have not found a relationship between the vaccine and autism. Studies investigating a link between thimerosal and autism have also been completed, and they have reported no link between thimerosal and autism. The MMR vaccine has never contained thimerosal.⁹

One reason parents continue to correlate the relationship between the MMR vaccine and autism is many children are diagnosed with autism around the same age as when the MMR vaccine is given. “One of the criteria used to make a diagnosis of autism is a language delay. Because children do not have significant expressive language under a year of age, doctors have to wait until 15 to 18 months to confirm a language delay and make the diagnosis. That’s about the same time as the MMR vaccination [around 2 to 3 years old], which leads some parents to wonder about autism and vaccination,” states an excerpt published by the Immunization Action Coalition.¹⁰

Consequences of Not Vaccinating

According to CDC, the consequences of declining childhood vaccination can result in a resurgence of many of the vaccine-preventable diseases. An outbreak can result in thousands, or even tens of thousands, of people to suffer, and in many cases, die. In addition, current very low rates of vaccine-preventable diseases would drastically increase because the bacteria that cause these diseases are still prevalent throughout the world. If childhood vaccination rates decline in the United States, only one case of a vaccine-preventable disease could trigger an outbreak. And, unvaccinated travelers and immigrants can easily bring diseases into the United States. What’s more, vaccine protection extends to all people in all communities. Not only are unvaccinated babies and young children at a much greater risk for contracting serious vaccine-preventable diseases, but they can transmit vaccine-preventable diseases and infect other people in the community.¹¹

Maintaining Community Immunity Threshold

To increase vaccination rates to maintain the community immunity threshold of at least 95 percent or higher, CDC and the 2016 NIS-Child survey recommend several actions health practitioners can implement:¹

• Educating parents about the importance of immunization and what can happen if children are not vaccinated;
• Informing parents that vaccine-preventable diseases caused hundreds of thousands of cases of illnesses and thousands of deaths every year in the United States before the 1920s when vaccines were not available;
• Reassuring parents that we can now protect children from 14 diseases (polio has not circulated in the United States since 1979, and smallpox has been eradicated worldwide); and
• Reminding parents that children should not have to suffer and possibly die from a vaccine-preventable disease, and advising them on childhood immunization schedules beginning within the first year of life.

The 2016 NIS-Child results indicate the immunization safety net is not reaching all children early in life. According to the survey report, coverage could be increased if health practitioners implemented evidence-based interventions such as:⁸

• Reminders for parents to eliminate missed opportunities to vaccinate their children;
• Standing orders to provide vaccinations whenever appropriate; and
• Immunization information systems to track vaccination administration.

Vaccines Offer the Best Protection Against Diseases

Vaccination is one of the best ways parents can protect their babies and young children from 14 potentially harmful diseases. “For children born between 1994 and 2016 in the United States, the CDC estimates that routine vaccinations will prevent an estimated 381 million illnesses, 24.5 million hospitalizations, and 855,000 deaths over the course of their lifetimes,” said Bertram Kelly, public affairs team lead in the Office of the Associate Director for Communications of CDC. Unfortunately, too many parents continue to opt out of vaccines for their children, increasing the chances of an outbreak of diseases that have been mostly eradicated in the U.S. As an authority parents of young children look to for advice, healthcare professionals must take every opportunity to clear up any misconceptions parents may have regarding vaccines’ safety and urge the timely vaccination of their little ones.