Because of their impact on public health, immunizations are considered one of the greatest medical achievements of modern civilization.1,2 Since this vital medical intervention became available in the 18th century, there has been a significant decrease in the incidence, prevalence, morbidity, and mortality of vaccine-preventable diseases.1 Between 1924-2019, more than 103 million cases of smallpox, polio, measles, mumps, rubella, hepatitis A, diphtheria, and pertussis are estimated to have been prevented thanks to the introduction of vaccines. In recent years, immunizations have helped prevent between 2 and 3 million deaths annually in the United States.3,4 In addition, endemic transmission of polio and rubella has been eradicated from the United States, and smallpox has been eradicated worldwide.1

Although childhood vaccination programs have helped contribute significantly to the positive impact of vaccines on public health, there are no formalized vaccination delivery programs for adults. As a result, vaccination rates are low among this patient population, increasing their susceptibility to serious illness and complications.5 Furthermore, vaccine-preventable diseases, including measles, have seen a resurgence over the last decade due to waning vaccination.6

On average, 50,000 Americans die of vaccine-preventable diseases each year, of which more than 99% are adults.1 Therefore, it is crucial that pharmacists understand the barriers impacting immunization rates among adults and actively engage in strategies to improve vaccination rates not only among high-risk groups but also among non–health care consumers (ie, those who are otherwise healthy and do not regularly seek out health care services).

IMMUNIZATION BARRIERS AMONG ADULTS
The US Public Health Service and multiple other stakeholders have identified barriers that impact adult immunization.1 Knowing these barriers is essential to creating strategies to engage adult patients and improve vaccination rates. These are the most common barriers to adult immunization:
  • Vaccines are low priority: The importance of vaccination among adults is a low priority in the United States.1 There is no formal vaccine delivery system for adults in the US health care system, and most employers—in contrast to schools that enroll children—do not require proof of vaccination for employment. Furthermore, there is a pervasive belief among American adults that if they are healthy, they do not need to receive immunizations or have wellness visits with their health care providers.7
  • Lack of information: A lack of information about vaccines is identified as a major contributor to the low vaccination rate among adults in the United States.1 The results of a survey of more than 2000 adults aged 19 to 74 years showed that 90% to 96% knew the tetanus vaccine existed but only 36% knew a booster dose was required every 10 years, and 74% thought a booster was only required after an injury.7 Similarly, 65% were aware of the pneumococcal vaccine, but 56% had not received it because their doctor had not recommended it.7
  • Vaccine hesitancy: Myths and misinformation concerning vaccines and their potential adverse effects are prevalent.1 As a result, adults may not inquire about immunizations out of fear of adverse effects or due to a dislike of needles. Some patients also object to vaccines for religious principles or cite individual rights.1
  • Lack of accessibility: The cost of vaccination, lack of transportation, language barriers, and incomplete records can all contribute to the lack of accessibility of vaccines.1
  • Systemic and operational obstacles: These include costs of immunizations, vaccine storage difficulties, and easily accessible immunization records.1 For example, in 2012, only an estimated 31% of family physicians and 20% of internists stocked all routinely recommended adult vaccinations.8,9 As a result, patients may have difficulty obtaining certain vaccinations and may be unaware of alternative health care facilities, such as pharmacies, that can give them vaccines.
PHARMACISTS AS IMMUNIZERS
Pharmacists have been involved in vaccinations since the mid-1800s, with the procurement and distribution of smallpox vaccine for physicians.4 Today, pharmacists can not only distribute vaccines, they can also immunize patients in all 50 states, the District of Columbia, and Puerto Rico. Currently, 61% of community pharmacies offer immunizations as a service to their community.10 Furthermore, their accessibility and convenience for patients can increase immunization acceptance.4

In addition, pharmacists have also created immunization programs that go beyond passive immunizing by actively identifying and administering vaccines to eligible patients.2 The majority of research evaluating the pharmacist’s impact on immunization rates has been for influenza and pneumococcal disease; however, most pharmacies who provide vaccines also provide the majority of the routinely recommended adult immunizations.4 Therefore, pharmacists can help bridge the gap for patients whose physicians do not regularly stock all the vaccines.

STRATEGIES TO ENGAGE NON–HEALTH CARE CONSUMERS
The accessibility of primary care in the United States is decreasing, in part, due to a rapidly aging population. US survey data show that the average wait time for an appointment with a primary care physician is about 20 days.11 Pharmacists are the most accessible health care provider and can help engage patients, who do not regularly seek out health care services, with the following strategies:
  • Provide counseling: Pharmacists interact with patients daily in their clinical practice regardless of the health care setting. They should assess a patient’s vaccination history at every encounter and educate patients on the importance of being up-to-date on any needed immunizations. A strong recommendation from a health care provider is a strong predictor of patient acceptance.1 For example, a 2016 systematic review found that increases in immunization rates resulting from a pharmacist recommendation were similar to those made by physicians or nurses.4
  • Increase accessibility of vaccinations: Pharmacies that offer immunizations can increase their accessibility by offering immunization services via walk-in visits and availability during extended hours. Immunization programs with these additional services have been shown to reach new patients (ie, individuals who do not currently utilize the pharmacy).1
  • Utilize immunization information systems: Immunization registries can assist health care providers in consolidating immunization records for individuals who have multiple providers. As a result, pharmacists can utilize these registries (where available) to identify immunization gaps at the point of care or when patients are unsure of their immunization record.
  • Participate in community-based advocacy programs: Pharmacists can reach new patients and non–health care consumers via community outreach.1 Examples include partnering with local community centers to promote wellness and needed immunizations via clinics, brochures, posters, and educational seminars.1 Pharmacists can also partner with local businesses to provide immunization clinics to help keep patients healthy in the workplace.
  • Provide vaccine administrative programs: Pharmacists can participate in vaccine administrative programs offering immunizations to improve public health in their community. Regardless of the strategy that is used to engage new patients who are not regular health care consumers, it is essential that the pharmacy team is appropriately trained and has adequate supplies and sufficient space for offering immunizations.1 Vaccine administrative programs should also have protocols in place for immunization emergencies and the prevention of needlestick and sharps injuries.
SUMMARY
Vaccines, as a medical intervention, have significantly decreased vaccine-preventable diseases; however, adult patient population immunization rates in the United States remain low, increasing the risk of serious illness and complications. The causes of these low immunization rates are multifactorial. Pharmacists are the most accessible health care provider; as such, they can help overcome these barriers. Employing strategies to reach not only high-risk individuals but also those who are non–health care consumers is essential to help improve immunization rates among the US adult population.
 

BRITTANY HOFFMANN-EUBANKS, PHARMD, MBA, is a clinical pharmacist and the Founder and CEO of Banner Medical LLC, a medical communications company.

REFERENCES
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