INTRODUCTION

Despite demonstrated vaccine effectiveness, concerns about vaccine safety continue to interfere with universal acceptance of some vaccines and misinformation abounds. In the last few years, early childhood immunization rates have slipped in some hot spots around the country, and in 2019, the United States (U.S.) very nearly lost its measles elimination status. (Diseases are considered eliminated if no chain of transmission in a given outbreak is sustained for more than 12 months.) The Centers for Disease Control and Prevention (CDC) confirmed 1,249 cases of measles between January 1 and October 4, 2019. This marked the greatest number of measles cases in the country since 1992. While cases were reported in 31 states, 75% of measles cases were linked to outbreaks in New York City and New York state, most of which were among unvaccinated children.¹ As of 2020, CDC reported that immunization rates remain lower in children who are at poverty level, covered by Medicaid, or receive no health insurance.² According to the U.S. Department of Health and Human Services, adults continue to be vaccinated at low and variable rates as well.³ Experts predict vaccination rates could drop even lower as a result of the COVID-19 pandemic with patients canceling medical visits in an attempt to avoid coronavirus exposure.

Recently, preventable diseases are rising again in the developed world because of vaccine myths that have reduced vaccination rates. These myths will continue to make an impact in the U.S. unless addressed. Barriers to adult immunization include concerns about adverse events, skepticism about vaccine effectiveness, lack of public knowledge regarding the adult immunization schedule, risks and consequences of vaccine-preventable diseases, and conflicting and inaccurate information about immunization in the mass media.⁴ This continuing education activity will provide pharmacy technicians with the facts and scientific research that dispel vaccination myths and explore the various reasons for refusal to become vaccinated.

VACCINE MYTHS AND TRUTHS

Numerous vaccine myths are circulating that lead to fear and incorrect conclusions about vaccine safety, efficacy, and necessity. To address concerns related to vaccination, the pharmacy technician must respond with sound scientific evidence to correct misconceptions. This section will explore these myths and provide evidence that will show specific fears about vaccinations are unfounded.

Vaccines and Autism

A study that has been retracted and discredited claimed the measles, mumps, and rubella (MMR) vaccination was linked to autism spectrum disorder (ASD) in children.⁵ Upon the study’s publication, critics quickly pointed out that the paper was a small case series with no controls, linked 3 common conditions, and relied on parental recall and beliefs. Investigations into this claim of a relationship between ASD and MMR vaccine uncovered the possibility of research fraud and unethical treatment of children. The investigation also uncovered the author’s conflict of interest through his involvement with a lawsuit against manufacturers of the MMR vaccine.⁶ By the time the publication finally retracted the paper 12 years later, few people could deny that it was fatally flawed both scientifically and ethically. Over the following decade, epidemiological studies consistently found no evidence of a link between the MMR vaccine and autism.^7-10

Autism spectrum disorder (ASD) rates have increased in the U.S. and other parts of the world. The increase parallels the expansion in the diagnostic criteria for autism that now includes spectrum disorders with a broader array of symptoms.¹¹ In 2014, CDC found that 1 of 68 children in the U.S. had ASD, which was approximately 30% higher than estimates reported in 2012.¹² The Institute of Medicine (IOM) Committee on Vaccines and Adverse Events released a report in 2011 using peer-reviewed literature to examine 8 vaccines given to children or adults including the MMR vaccine. This committee concluded that current childhood and adult vaccines are very safe and adverse events are rare.¹³ A 2013 CDC study added to the research showing that vaccines do not cause ASD. The study looked at the number of antigens from vaccines during the first 2 years of life and showed that children with ASD and those who did not have ASD received the same total amount of antigens from vaccines.¹⁴

Thimerosal, a common preservative, is an organic compound containing mercury. Thimerosal has been used safely since the early 20^th Century as a preservative in many vaccines. Over time, concerns were raised about its safety because some organomercurials were increasingly associated with neurotoxicity. Specifically thimerosal was thought to be linked to ASD. A 2004 IOM safety review rejected the causal relationship between thimerosal–containing vaccines and ASD.¹⁵ Since 2003, CDC has funded 9 studies and found no link between either thimerosal-containing vaccines and ASD or MMR vaccine and ASD in children.¹⁶ Regardless, thimerosal has since been removed or reduced to trace amounts in all childhood vaccines except for some flu vaccines. Manufacturers took this precautionary measure to reduce all types of mercury exposure in children before studies determined that thimerosal was not harmful.⁴¹ Clear evidence, sound scientific research, and avid patient education will hopefully close the door on this damaging vaccine scare that falsely linked the MMR vaccine and thimerosal with ASD.

Guillain-Barré Syndrome

Guillain-Barré syndrome (GBS) is a rare but serious health disorder in which a person's own immune system damages nerve cells, causing muscle weakness, sometimes paralysis, and infrequently death. In Western countries, the cause of 60% of GBS cases is unknown. The number of cases with unidentified causes peaks in winter, and these cases are commonly preceded by respiratory tract infection or influenza-like illness in 60% to 70% of patients.¹⁷ Vaccinations have also been implicated in GBS; an example is the influenza vaccine used during the mass vaccination campaign against swine influenza in the United States from 1976 through 1977.¹⁸

The influenza A (H1N1) 2009 vaccination has also been linked to GBS. This vaccination program was a large mass vaccination initiative. Based on the vaccination program’s size and scope, the National Vaccine Program Office structured a project to monitor vaccine adverse events. The adverse event monitoring project identified a small increased risk of GBS after vaccination. It found an increase of approximately 1.6 excess cases of GBS per million people vaccinated.¹⁹ This finding was consistent with previous estimates of the disorder after seasonal influenza vaccination. CDC monitors for GBS during each flu season and data on an association between seasonal influenza vaccine and GBS have fluctuated from season-to-season. When risk has increased, it has consistently been in the range of 1 to 2 additional GBS cases per million influenza vaccine doses administered. Studies suggest that it is more likely that a person will develop GBS after contracting the flu than after vaccination.²⁰ It is important to keep in mind that severe morbidity and mortality are significant risks after influenza infection, and vaccination prevents many complications and deaths. In other words, the benefits may be worth the small risk of contracting GBS from the influenza vaccine.

Sudden Infant Death Syndrome

Sudden infant death syndrome (SIDS) peaks when babies are between 2 and 4 months old, a time when pediatricians also give infants many vaccines. The overlap of peak SIDS incidence and the period of initiation of the childhood vaccination series led to questions about a causal relationship between vaccines and SIDS. Studies have shown that the association between infant vaccination and SIDS is coincidental and not causal. A study that examined the Vaccine Adverse Event Reporting System (VAERS) reports of death after vaccination concluded that patients and providers may be more likely to report deaths in VAERS if the child recently received a vaccine, and not because a causal relationship exists.²¹ The Institute of Medicine (IOM) 2003 safety report also reviewed the relationship between SIDS and vaccines and concluded that vaccines do not cause SIDS.²² In addition, SIDS has decreased dramatically due to the 1992 American Academy of Pediatrics recommendations to place infants on their backs to sleep and the 1994 National Institute of Child Health and Human Development’s Back to Sleep campaign to educate parents and caregivers about reducing the risk of SIDS.²³

Safety of Multiple Vaccinations

Parents may have concerns that an infant’s immune system cannot handle so many vaccines. From the moment babies are born, they are exposed to numerous bacteria and viruses daily. Eating food or playing outside introduces new bacteria into the body and numerous bacteria live in the mouth and nose alone. Infants place their hands or other objects in their mouths hundreds of times each day, exposing the immune system to still more pathogens. When children contract a cold, they are exposed to up to 10 antigens, and exposure to “strep throat” introduces about 25 to 50 antigens.²⁴ Each vaccine in the childhood vaccination schedule has between 1 and 69 antigens.²⁴ CDC reports that a child who receives all the recommended vaccines in the 2018 childhood immunization schedule would be exposed to up to 320 antigens through vaccination by age 2.²⁴ A 1994 IOM report stated that the number of separate antigens contained in childhood vaccines represents a burden on the immune system that would be unlikely to be immunosuppressive.²⁵ In fact, CDC states that giving different childhood vaccines during the same visit is advantageous because it means fewer office visits. Building protection from infectious diseases as quickly as possible confers protection during the vulnerable early months of a child’s life.²⁴

Presence of Unsafe Toxins

People have concerns about the use of additives in vaccines and their potential for toxicity. It’s true that these chemicals are toxic to the human body in certain levels, but U.S. Food and Drug Administration (FDA) approved vaccines contain only trace amounts of these chemicals. Prior to licensure, as part of its evaluation, FDA takes all ingredients of a vaccine into account, including additives.²⁶ Table 1 lists vaccine additives and their potential concerns related to toxicity that have been proven untrue with scientific research.

Hygiene and Sanitation Decrease Disease - Not Vaccines

Vaccines do not deserve all the credit for eliminating infectious disease. Better sanitation, nutrition, and antibiotics helped as well. Historically, the U.S. employed effective sanitation and hygiene efforts but children still routinely died of polio, measles, rotavirus, pneumococcal meningitis, and all other infectious diseases for which vaccination had yet to become standard. If better hygiene and sanitation were solely responsible, why has each vaccine-preventable disease been controlled at different times? Measles, rubella, mumps, diphtheria, and polio have all been eliminated in the U.S. at various times.²⁸ The argument for hygiene and sanitation alone clearly does not have legitimate evidence to support the claim.

Vaccines Can Cause the Disease They Prevent

Vaccines can cause mild symptoms resembling those of the disease they are designed to prevent. A common misconception is that these symptoms signal infection. With live vaccines, mild symptoms may sometimes occur. They aren’t harmful and in fact show that the vaccine is working by producing an immune response. Live attenuated vaccines use a weakened form of a virus that contains antigens that stimulate an immune response. Such viruses have been weakened so they cannot cause the disease but instead stimulate an immune response after 1 or 2 doses. Inactivated or killed vaccines are made from bacteria or viruses that have been killed by heat or chemicals.

• Patients can't catch a disease from an inactivated vaccine because the infectious agent can't reproduce, but the dead virus or bacteria is still enough to stimulate the body's immune system.
• Subunit vaccines are inactivated vaccines made from a small part of the virus or bacteria.
• Partial viruses and bacteria are unable to reproduce and cause disease.

As stated, full-blown disease from a vaccine would be extremely unlikely. However, one exception was the live oral polio vaccine, which could very rarely mutate and cause polio. This was a rare, but tragic, side effect of this otherwise effective vaccine. Because the trivalent oral polio vaccine (not the virus) caused 8 to 10 cases of polio annually, the U.S. switched its recommendation to an inactivated polio vaccine. The trivalent oral polio vaccine was better at stopping wild natural polio virus spread, but since wild (natural) polio had been eliminated from the Western Hemisphere, this advantage was no longer a consideration in the U.S. The switch to inactivated polio vaccine eliminated the small chance of contracting polio from the live oral vaccine. Inactivated polio vaccine has been used exclusively in the U.S. since 2000.²⁹

The Disease is Eliminated. Why Vaccinate?

Thanks to herd immunity, as long as most people are immunized in any population, even the unimmunized will be protected. With so many people who are resistant to a disease, an infectious disease will never be able to spread. This is important especially because a portion of the population such as those who are immunocompromised or pregnant women will always be unable (at one time or another) to receive all required vaccines. If a substantial portion of the population were to decide not to vaccinate, opportunities would open for spreading bacteria and viruses that were once controlled. International travel also carries risk to those who are not immunized to diseases that may not be a threat in the U.S. but may be common elsewhere. If someone were to bring back a disease from abroad, it would open a window for mass infection if vaccination was below herd immunity levels in this country. This was the case with the measles outbreak in New York. CDC traced the outbreaks to unvaccinated travelers who brought measles back from other countries and spread the disease to unvaccinated children.¹

Natural Immunity is Better than Vaccine-Acquired Immunity

In some cases, natural immunity may result in a more robust immune response to the disease than vaccination provides. However, the benefits far outweigh the risks. Let’s say, for example, that a parent decided not to have a child immunized for measles. For every 1,000 children who become infected with measles, 1 to 3 will die from respiratory and neurologic complications.³⁰ In contrast, the risk of having a serious adverse event from a measles-containing vaccine is documented to be 3.5 to 10 per million doses of vaccine.³¹ The benefits of vaccination in this case clearly outweighing the risks.

Vaccines are Derived from Aborted Fetuses

In the 1960s, fetal tissue was used to create 2 different cell lines that have been used to develop vaccines, including hepatitis A, rubella, varicella, and zoster vaccines.³² These cells originally came from tissue obtained from 2 fetuses that were legally and electively aborted. Scientists found that the cell lines derived from fetal tissue were more useful than existing animal cell lines for cultivating viruses needed to develop vaccines. The same cells have continued to grow in a laboratory and are still used to make vaccines today. However, no additional fetal cells have been harvested since then,³² but the topic remains controversial because of the original source of the vaccines.

Vaccines May Alter the Human Genome

A DNA or RNA vaccine takes a small part of the virus' own genetic information, just enough to spark an immune response, and relies on the human body’s own cells for production of the target protein (antigen).³³ A misconception exists that vaccines using DNA or RNA obtained from a virus can alter the host’s genetic code, in other words changing human DNA and/or RNA. Genetic vaccines do not enter the human genome; they merely imitate what happens when our body is infected with a virus. To replicate and spread, a virus inserts its own DNA or RNA into our cells. The vaccine does that as well, but in a controlled manner. The vaccine retains only a portion of the virus (e.g., a specific strand to encode for a protein the body recognizes as foreign), but not enough to infect the host. When humans contract a viral infection naturally, the virus’s DNA or RNA enters our cells, but the virus does not usually leave its DNA behind to become part of the human genome.³³

Vaccine concerns should be taken seriously, and misconceptions should be thoroughly discussed to ensure that patients have reliable information and are informed about the risks associated with failure to vaccinate. By providing education to patients, pharmacy technicians can refute these vaccine myths with scientific-based evidence.

REASONS FOR REFUSAL

In addition to vaccine myths, there are several reasons patients may choose not to be vaccinated. Based on the concept of herd immunity, society has a stake in protecting public health, but this is not to say that a patient’s concerns and beliefs regarding vaccination are not valid. Each patient’s concerns must be examined individually to decide what is best for the patient and society-at-large. Table 2 lists reasons for refusal to vaccinate that have been documented in the literature.

STRATEGIES FOR TALKING TO PATIENTS

Health care providers can use a variety of approaches to respond to vaccine-related concerns and to correct any misconceptions. According to a study in the American Journal of Medicine, the most common reasons for not receiving immunizations were lack of physician recommendations and mistaken assumptions that healthy people do not need immunizations.³⁵ It may be helpful to have the CDC adult immunization schedule (located here: https://www.cdc.gov/vaccines/schedules/hcp/imz/adult.html) on hand to review the recommended vaccinations for adults. In most cases, however, a lengthier conversation will need to take place. Patients perceive health care professionals who take the time to listen to concerns and respond thoughtfully as trustworthy sources. Even patients who were previously distrustful of official sources may be more willing to accept information about vaccinations from a trusted professional after a thorough conversation.³⁶

One of the most important aspects throughout the entire interaction is keeping an open mind and creating a comfortable environment by listening first. If patients decline the vaccine, ask them about their hesitancy. Vaccine hesitancy is normal and natural and call for compassion and acknowledgement of the concern. When providing information to address concerns and misconceptions, avoid medical jargon that may confuse patients. It may be helpful to explain that VAERS, administered by CDC and FDA, provides an active surveillance system that collects information about adverse events resulting from vaccinations nationwide. By monitoring adverse events, the government can ensure that vaccines’ benefits far outweigh the risks. Finally, telling patients what to expect if they were to receive the vaccination may help to ease some of their fears. This may include addressing all potential adverse effects and the process of receiving the vaccination at the pharmacy.

Every pharmacy technician must be willing to accept patient autonomy, which means granting each patient the independence and the freedom to choose a course of action based on what he or she decides is best. It is important to remember that the decision not to vaccinate is reversible. Continue working on building a trusting relationship and revisit the topic of vaccination when you encounter the patient again. As the relationship develops over time and you gain patients’ confidence, they may just change their mind and consider vaccination. Table 3 lists quick tips for talking with patients about vaccinations.

VACCINE DECISION MAKING AND THE IMS MODEL

The Information-Motivation-Strategy (IMS) Model was originally developed as a 3-factor model to improve patient adherence. The model identifies 3 categories to guide patients toward adherence including information, motivation, and strategy. ³⁷ This model is also useful in discussing and moving patients from vaccination hesitancy to vaccine acceptance in the same manner as it encourages adherence. The information component of the model highlights the importance of patient knowledge and its achievement through effective communication. To receive and understand information adequately, patients need the opportunity to ask questions and have them answered. Another factor that is relevant to patient understanding is participation in medical decision-making.³⁷ When patients are adequately informed, they are better able to share in the decisions that affect their health and likewise more willing to accept vaccination if they are part of the decision process.

Patients only accept treatments they believe in and this is a necessity in motivating patients to become vaccinated. The Health Belief Model is 1 of the earliest theoretical models to attempt to predict why people engage or don’t engage in health behaviors. The model assumes that people will take action to prevent illness if they³⁸

• regard themselves as susceptible to a condition (perceived susceptibility)
• believe it would have potentially serious consequences (perceived severity)
• believe that a particular course of action available to them would reduce the susceptibility or severity or lead to other positive outcomes (perceived benefits)
• perceive few negative attributes related to the health action (perceived barriers)

Patients who believe that the consequences of not being vaccinated are severe are more likely to be vaccinated versus those who believe that the consequences are less serious. Patients’ beliefs about the value of the treatment (i.e., vaccinations’ benefits and effectiveness) and patients’ confidence that practical barriers to achieving vaccination can be overcome are also meaningful in influencing motivation.³⁷ In this case barriers may be financial concerns, physician access, or pharmacy access.

The last factor in the IMS model discusses strategy. Patients must have the tools and strategies necessary to overcome the barriers standing in the way of g vaccination. The patient may need assistance in determining what vaccinations are recommended and how to obtain them. Discussions on which vaccinations require a prescription and where the vaccination can be administered (pharmacy or a physician office) is valuable information that will help move a patient toward vaccination. Hectic schedules are also a barrier to successful vaccination. Assisting the patient with convenient vaccination scheduling times will help make the vaccination decision easier if it can be accomplished with little adjustment to the patient’s daily routine.

The IMS Model illustrates that knowledge, commitment, and ability are all crucial for maximizing vaccine acceptance. In addition, the model emphasizes the importance of effectively providing education, motivating, and strategizing with patients to overcome barriers. Table 4 lists recommendations for applying the IMS model to vaccinations.

Case Example

Conversations with patients who are reluctant to receive the influenza vaccine can be difficult. Patients seek an influenza vaccine for many reasons including concerns for their own health, the health of a family member, or societal pressure. Some patients you encounter may have never had the vaccine and others hold tight to the widely accepted misconception that you can develop the flu from the vaccine. In this case, one of your regular patients comes to the pharmacy and your interaction looks like the following.

Pharmacy technician, “Have you had your flu shot this year?”

Patient responds,“I didn’t get it and I am not interested in getting it.”

How do you continue the conversation from here? Techniques such as motivational interviewing can make these conversations easier and lead to changes in patients’ behavior and beliefs about vaccinations. A version of the motivational interviewing technique is the elicit—provide–elicit model, which can be useful in this type of interaction.³⁹ In this model the pharmacy technician would be able to:

• Elicit: Ask the patient questions to elicit the level of understanding
• Provide: Fill in knowledge gaps and remove misconceptions
• Elicit: Determine how this information pertains to the patient

Motivational interviewing techniques suggest that the pharmacy technician should ask permission to provide advice when attempting to change a health-related behavior.⁴⁰ By using this method, the patient and the technician can have a discussion, rather than the patient perceiving the technician’s comments as a lecture. The conversation may begin with the following question.

Pharmacy technician,“Would it be OK if I shared some information with you about the flu vaccine?”

Assume the patient says it is permissible to continue the conversation. Let’s put some of the effective communication tips just discussed to use. Remember to keep an open mind and approach the patient with concern. If a patient declines the vaccine, ask them about their hesitancy. It might look something like this.

Pharmacy technician,“May I ask why you don’t want to get the flu shot? What have you heard about the vaccine?" 

Patient response, “Every time my wife gets the vaccine, she gets sick. The flu isn’t that bad, and I rarely ever get sick so why should I get the vaccine?”

The next part of the conversation starts with your acknowledgement of the concern and it may look something like the conversation that follows.

Pharmacy technician, “You see your wife get sick after getting the vaccine and you never get the flu anyway so I can’t blame you for not wanting to be vaccinated yourself.”

Now you are ready to share information and you continue with the conversation as follows.

Pharmacy technician, “Vaccines can cause mild symptoms resembling those of the disease they are protecting against. A common misconception is that these symptoms signal infection. With live vaccines, these mild symptoms may sometimes occur. This isn’t harmful and in fact shows that the vaccine is working by producing an immune response to the vaccine. Live vaccines use a weakened form of a virus and because they have been weakened, they cannot cause the disease. Inactivated vaccines are made from bacteria or viruses that have been killed by heat or chemicals so you can't catch a disease from this type of vaccine because the infectious agent can't reproduce. Flu shots are made with either inactivated viruses or with only a single protein from the flu virus so they cannot replicate and cause the flu in a human.”

Patient responds, “OK, that makes sense, but I still don’t really get sick and if I get the flu big deal.”

It is time to insert more valuable information and remember not to use medical jargon.

Pharmacy technician, “Perhaps most people will recover in a few days to a few weeks. However, some people will develop serious complications such as pneumonia, which can lead to hospitalization and possibly death. Other parts of your body can be infected as well such as your heart, brain, and kidneys and the flu can even trigger a chain reaction throughout your body that is an extreme response to the flu infection. Without timely treatment, this reaction can rapidly lead to death.I hope you can see that getting vaccinated is a safer choice to prevent some life-threatening consequences from getting the flu. At the very least it can prevent you from getting sick, losing time at work, seeing your doctor, perhaps even getting a medication and you don’t have to feel flu symptoms for 2 weeks.”

The patient may have more questions, or this may be just enough to convince him to receive the influenza vaccine. Remember to be willing to accept patient autonomy and that the decision not to vaccinate is a reversible one. Continue working on building a trusting relationship and if necessary, revisit the topic of vaccination when you encounter the patient again.

CONCLUSION

Vaccine concerns should be taken seriously, and misconceptions should be thoroughly discussed to ensure that patients have reliable scientific evidence and are informed about the risks associated with failure to vaccinate. Vaccine hesitancy may be related to a constellation of factors including fear of adverse effects; lack of perceived susceptibility, severity, or benefit; social media influences; religious or philosophical beliefs; and the necessity and effectiveness of vaccinations. Pharmacy technicians must approach each conversation with an open mind and a genuine desire to help patients understand vaccination’s importance for their own health and the health of family members and society-at-large. By providing education with caring, competent, and effective communication skills, pharmacy technicians can help reduce vaccine hesitancy and pave the way to vaccine acceptance..

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