Trends in U.S. Vaccine Compliance

THE NEED FOR safe, effective and easily accessible vaccines has never been more evident than during the COVID-19 pandemic and the unprecedented global crisis it has caused. The first several months of this year alone served as a highly illustrative testament to how crucial protection is against pathogens and their effect on personal lives, cultures and economies. The world has now again faced an international pandemic requiring widespread social distancing and even isolation. Only time will tell how quickly and successfully governments and healthcare systems respond, and how soon a vaccine to prevent it is developed.

In the United States, the importance of vaccines is always at the forefront among healthcare professionals, researchers and others who have factual information about them. For example, since 1994, the Centers for Disease Control and Prevention (CDC) has collected data to estimate vaccination coverage among U.S. children. Because a number of vaccines are primarily distributed during childhood, vaccinated children are prepared for better health throughout the rest of their lives. Today, CDC and other health organizations such as the Blue Cross Blue Shield Association (BCBSA) remain diligent in their pursuit of herd immunity, safe vaccines and presenting scientifically accurate information to the public. Because of organizations like BCBSA, hundreds of millions of American children and adults are spared each year from contracting serious and potentially lethal illnesses as a result of their hard work to promote vaccine compliance.

Yet, each year, the perpetual question is: How are Americans — especially parents — responding to healthcare’s call to vaccinate? And, depending on that answer, how can healthcare workers best respond to encourage more appropriate vaccine compliance? (See “Counteracting the Anti-Vaccine Movement” on p.24.) “Medical providers shouldn’t underestimate their influence,” encourages Hillary Johnson, MHS, an epidemiologist with the Massachusetts Department of Public Health’s Immunization Program. “A strong provider recommendation for vaccination can go a long way in guiding a parent’s decision to vaccinate.”

Vaccine Compliance Among Young Children

In case there is any question regarding the importance of vaccination in young children, consider the following statistics: Since 2010, influenza-related hospital stays for children under age 5 years have ranged from 6,000 to 26,000 in the United States each year. And, remembering that vaccinated children mean vaccinated adults, an estimated 850,000 to 2.2 million people in the U.S. have chronic hepatitis B.¹

Perhaps the best news, according to the BCBSA data from 2016 to 2017, is early childhood vaccination has risen to 77 percent for the CDC-recommended schedule of vaccinations, which includes diphtheria, tetanus, polio, hepatitis A and B, pneumococcal, rotavirus, measles, varicella and pertussis. “We believe that more and more people are realizing the information that had been put out on anti-vaccination was not based on science,” says Brian Harvey, executive director of research and analytics at BCBSA. “And so they’re starting to vaccinate their children at a higher rate. There are more children being vaccinated within that first 27 months.”

The bad news is 23 percent of children ages birth to 27 months were not vaccinated. That is largely because “a child might actually be ill and may miss a well visit, causing them to be unable to complete their visits within the 27-month window. What we would stress to all the parents is that it is very important to complete those well vaccinations on time, particularly given viral diseases,” adds Harvey. “If a child is not vaccinated, they’re not protected. Parents want to get those completed as quickly as they can, which really is that 27-month window, or as quickly as they can do it for their child.”

Harvey also cautions that documented parental/guardian refusals in BCBS Axis data increased nearly 70 percent for children born in 2013 compared to children born in 2010 (4.2 percent versus 2.5 percent, respectively), and most refusals were at the child’s birth. This means if parents are going to refuse to vaccinate their children, most will refuse at the very beginning. “The important thing,” explains Harvey, “is for agencies and healthcare workers to be educating parents how important it is to vaccinate their children and how important it is to get them protected against these diseases that can be fatal.”

“There is still wide geographic variation in vaccine rates across the country,” says Harvey. “For example, in 2016, the seven-vaccine series completion rates by state for children in the 2013 birth cohort ranged from a high of 86 percent in North Dakota to a low of 63 percent in Nevada.” This variation might be because physicians could more effectively communicate the importance of vaccines, or because certain regions of the United States seem more prone to accept false anti-vaxxing information. For example, regarding the 2019 measles outbreak in this country, Harvey explains, “There’s quite a bit of geographic variation that you can see in our data around that, too. When you look at the antivaccination trends, they track very closely with the news cycle from the last year. New York has the highest anti-vaccination rate of 8.4 percent. So, that’s significantly above the national average of 6 percent. And then we’ve got Washington state at 7 percent. So, both of those places were a hotbed for the measles outbreak because of the percentage of children who had not been vaccinated due to religious reasons and other cited exceptions. Those states also had the loosest physician exception policies. Since then, doctors have been tightening those up given the outbreak. And, we hope that when we look at 2019 data and 2018 data, we’re able to see that trend going down and the number of people refusing vaccinations actually going down in the United States.”

How can physicians and other healthcare providers improve vaccine compliance rates for children? According to Vincent Nelson, MD, chief medical officer (interim) and vice president of medical affairs at BCBSA: “Early childhood vaccination rates continue to improve among commercially insured children in the U.S.” However, he says, “There is still wide geographic variation in vaccine rates across the country. Failure to attend routine well-child visits is the predominant reason identified for undervaccination among commercially insured children. There are reputable sources such as the Community Preventive Services Task Force, which makes a guide available that is supported by the CDC and has evidence-based interventions for increasing appropriate vaccination.”¹

Adolescent Vaccine Compliance

Among youth between 10 years and 18 years of age, the human papilloma virus (HPV) vaccine is of most concern since it is grossly underutilized. HPV vaccination coverage, as of 2016, shows 60 percent of adolescents 13 years to 17 years old have started the HPV series. And each year in the U.S., an estimated 31,500 newly diagnosed cancers in men and women are associated with HPV.¹ “Blue Cross Blue Shield of Alabama is encouraging physicians to boost HPV vaccination rates by including metrics in their value-based payment programs for physicians,” says Dr. Nelson. And, such movements are occurring in other states as well.

According to Harvey, parents find the HPV vaccine the most confusing because it is a series of shots that is often poorly explained by physicians and medical literature. As a result, parents tend to avoid it. “Just the unmasked potential of what could have happened and what should have happened [with the HPV vaccine] if we actually had full herd immunity levels of 80 percent vaccination levels for boys and girls is worth mentioning,” says Harvey. “If we had been able to get to [80 percent], there are a number of physicians who claim we would have eliminated cervical cancer by now. Cervical cancer would not be a concern because it’s almost always translated from the HPV virus. If we can only educate parents that they do need to get this.”

In some states, physicians present the HPV vaccine as elective. But, Harvey says, “This is not an optional vaccine. This is something that their children should receive. There’s no downside risk to it. The biggest challenge that I think we have right now is the fact parents don’t understand it. We did a survey and asked parents why they weren’t vaccinating their children. The No. 1 reason is that they just don’t understand it. And, they’re getting conflicting information, and they think it’s optional. They don’t realize that it could really protect their children.”

Stigma also plays a role in parents underutilizing the HPV vaccine. “Parents don’t want to think of their child as an adult when they’re only 12 or 13,” Harvey says. “This vaccine requires a parent to think of the child as an adult, and what that adult might actually be doing later in just a few short years. In states where the vaccine isn’t presented as optional, North Dakota for example, there are very high vaccination rates. We talked to Blue Cross Blue Shield of North Dakota and asked them why this was. They told us that the vaccine is presented along with Tdap and meningococcal as nonoptional. They added that when a local doctor says, ‘These are the three vaccines you need to get,’ those are the three vaccines that patient gets.

“In other states where the HPV vaccine is presented as an option, people make the choice not to vaccinate. Then, they do a Google search and find all manner of anti-vaxxing information that gives them pause or scares them. So, parents need better information on that. And I think, around all vaccines, if there was better information available around the lack of risk for these vaccinations and the significant upside for all of them, there would be greater adherence and greater vaccination rates among our population.”

Adult Vaccine Compliance

While there is not a required vaccine schedule for adults, the annual influenza (flu) vaccine is probably the most important. According to Harvey, “Some vaccines, like tetanus and the flu, do need to be refreshed on a regular basis. Again, it’s important that people understand, just specifically looking at the flu and the flu shot, that even a partially effective flu vaccine has significant impact on what type of symptoms you’re going to get and how severe your flu is going to be. If you’re particularly in the at-risk population such as children or people who have underlying health conditions, or those over 60, those people should be vaccinated on an annual basis regardless for the flu. And, regardless of any news report as to whether or not that particular vaccine is a great match against the flu, the vaccine is going to help even if it isn’t a complete match. People don’t often hear that.” Physicians, he said, must make that point clear to each patient.

Future Projections

What is likely to happen if vaccine compliance does not improve, or even worsens, among each group? Dr. Nelson addresses this possibility, explaining, “As vaccine rates fall, we put our population at risk of losing community immunity and protection from preventable diseases. Young children and persons with chronic conditions such as heart disease are especially vulnerable. Another group of people that everyone is concerned about are those who are receiving treatment for cancer conditions. Most vaccine-preventable diseases are viruses, which can spread quickly before an individual may realize that they are ill. Adequate vaccination is the best prevention.” Once again, healthcare providers are the most influential sources of appropriate vaccination information.

With regard to COVID-19, Dr. Nelson explains that people respond to such dramatic illnesses with more receptivity to a vaccine, even though a vaccine may still be in development. But, people often ignore this fact when it comes to the flu. Flu is pandemic in North America, and although there is a vaccine, thousands die from it each year. News coverage likely plays a role since flu deaths are rarely reported with such vigor. “Novel diseases such as coronavirus may create fear and anxiety among people who may not understand their risks,” says Nelson. “People look to various sources for information to help them decide what steps they should take to protect themselves. The best ‘vaccine’ against fear and anxiety is education. Blue Cross and Blue Shield companies provide timely and trusted information to their members through a variety of communication channels and maintain a state of readiness to respond to unusual outbreaks. BCBSA also supports clinical providers so that they have resources at hand to meet member needs.”

Indeed, such support is crucial, especially since flu vaccination rates reported by CDC speak to the misinformation surrounding the vaccine. In 2018, only 50.4 percent of children age 6 months to 17 years received an influenza vaccination, and only 34.2 percent of adults aged 18 years to 49 years received one. And, while 46.8 percent of adults aged 50 years to 64 years were vaccinated against the flu, and rates were even higher among adults aged 65 and older at 68.7 percent, that is still far too low.²

How vaccine compliance in general might affect COVID-19 will depend on time, among other factors, including news coverage and patients having appropriate literature on side effects and the importance of being protected. Right now, however, we can at least take some comfort in knowing vaccination rates, overall, have been on the rise. It is hoped that trend will continue and patients will come to understand many illnesses are preventable entirely.