Immunization Practices in 2018: Challenges and Opportunities

July 26, 2018



The development of vaccines has been invaluable to global welfare.1 For example, childhood immunization prevents 2 million to 3 million deaths per year, according to the World Health Organization, and the Centers for Disease Control and Prevention (CDC) has reported that 16 diseases are under control or considered eradicated by vaccination.2,3 In the United States, among children within a recent 20-year birth cohort, vaccination will prevent an estimated 21 million hospitalizations and 732,000 deaths.3 From a financial burden perspective, this results in a net savings of $295 billion in direct costs and 1.38 trillion in total societal costs, according to a 2014 CDC report.3

By improving the health of the global population and saving millions of lives in a cost-effective manner, vaccines represent an important milestone in the trajectory of medicine and healthcare more broadly.4 However, despite the unmistakably positive impact that vaccines have had on public health, several notable gaps in knowledge and barriers to access limit their potential in the healthcare spectrum. Rates of adult vaccination are far below recommended levels, while community pharmacies, despite offering convenient and potentially cost-effective means for vaccination, remain underused sources of vaccine administration. Overcoming these challenges requires health systems, payers, and regulatory groups to take significant steps to boost education and awareness efforts and increase access to vaccine coverage. This article examines current reported vaccine rates and potential population health strategies to improve overall coverage.

Vaccine Rates and Recommendations

The CDC and other institutions recommend that individuals receive vaccines throughout life to prevent the incidence, prevalence, morbidity, and mortality of vaccine-preventable diseases. Serious diseases that occur in adults that can be prevented by vaccines include varicella, diphtheria, influenza, hepatitis A, hepatitis B, HPV, measles, meningococcal disease, mumps, pneumococcal disease, rubella, shingles/zoster, tetanus, and pertussis.5

The CDC’s Advisory Committee for Immunization Practices (ACIP) publishes recommendations for childhood and adult vaccinations (Table).6 Immunization recommendations are grouped according to age for adults 18 to 65 years old and adults 65 years old and above. The current recommendation lists vaccines against influenza; tetanus-diphtheria (Td); tetanus-diphtheria-acellular pertussis (Tdap); varicella; human papillomavirus (HPV); herpes zoster; measles, mumps, and rubella (MMR); and Streptococcus pneumoniae. Depending on the individual’s specific indications, other vaccines may be advised. These include vaccines against hepatitis A and B, meningococcus, and Haemophilus influenzae type b.7

Despite recommendations that adults receive routine vaccinations throughout their lives, rates of adult vaccination in the United States are low. Every year, at least 45,000 adults in the United States die from vaccine-preventable diseases.8 Patients who go without routine or recommended vaccinations cost the United States health system approximately $10 billion per year.8 Moreover, although the majority of people who die from vaccine-preventable infections had visited their healthcare provider in the year before their death, they still were not vaccinated.9 This finding further highlights the susceptibility of American adults to deadly diseases based on the inadequacy of the current vaccination rates.

The CDC’s Healthy People project has set targets for adult vaccination rates based on various disease states and age groups. The target goal of 90% coverage was not met for influenza vaccination (67%) and pneumococcal vaccination (60%) were not met in 2010, despite gains over the previous decade.10 The target coverage rate for 2020 is 70 percent for influenza.11

Herpes Zoster

Herpes zoster results from the reactivation of varicella zoster virus through latent infection, causing a painful vesicular rash.12 The incidence rises significantly among patients aged 50 to 60 years and continues to escalate with age. The global incidence of herpes zoster is increasing due to prolonged life expectancy and the aging population.13 In 2012, approximately 20% of adults aged 60 years or older reported receiving a herpes zoster vaccination for the prevention of shingles, up from 15.8% the previous year.14

Following the October 2017 FDA approval of a recombinant zoster vaccine (RZV) to prevent shingles in adults aged 50 years and older, the ACIP began recommending RZV in individuals with competent immune systems, given as 2 doses. For individuals aged 60 years or older, RZV or zoster vaccine live can be given.15

Findings from a recent 10-year postmarketing safety review of the zoster vaccine live virus revealed a favorable safety profile, consistent with that seen in clinical trials and postlicensure studies.16 The review concluded that the zoster live virus vaccination is effective and offers protection against postherpetic neuralgia in older individuals. Additionally, a study in the United Kingdom showed that the zoster vaccine may be more cost effective than estimated previously.17

HPV

Adolescents should routinely receive the HPV vaccine at age 11 to 12 years, as per ACIP recommendations.18 The vaccine, which is indicated in males and females aged 9 to 26 years, is administered in 2 shots, with the second 6 to 12 months after the initial shot. For children aged 14 years or older, 3 shots should be given over 6 months.19

In 2016, CDC surveillance for HPV adolescent vaccination rates revealed that coverage of at least 1 dose among teens was 60.4%, and 43.4% were up to date with the recommended series for HPV.20 CDC experts note that although vaccination coverage among teens continues to improve overall, substantial opportunities exist to further increase prevention efforts for HPV-associated cancer. The Healthy People 2020 target is 80% coverage for the HPV vaccination (Figure).11

Importantly, 2 types of HPV are responsible for 70% of cervical cancers and precancerous cervical lesions,18 both of which can be prevented by the vaccine.

Influenza and Pneumococcal Disease

The ACIP recommends a yearly seasonal influenza vaccination for all individuals aged 6 months and older who do not have contraindications.21 Early surveillance from the 2017 influenza season revealed that, despite the recommendations, only approximately 40% of children and adults in the US had received an influenza vaccination.21 Even worse, the influenza vaccination coverage for adults aged 18 to 49 years decreased by 3.7% compared with the same time the previous season.21 Although researchers continue to emphasize that the annual influenza vaccination has a significant public health benefit and durable safety, many people are still unvaccinated.21

Pneumococcal pneumonia—the most common form of pneumococcal disease in adults—is estimated to affect about 900,000 Americans each year.22 According to the CDC, approximately 5% to 7% of individuals who need care in a hospital because of the disease, end up dying from it.22 As many as 400,000 Americans are hospitalized annually from pneumococcal pneumonia, and about 90% of invasive cases are in adults. In 2013, the CDC reported an estimated 3700 deaths from pneumococcal meningitis and bacteremia.22

In 2016, influenza and pneumonia together were the eighth leading cause of death for Americans 65 years of age and older,23 partially due to vaccine nonadherence; 90% of total deaths were among the elderly.24

The CDC’s recommendations for all adults aged 65 years and older to receive the pneumococcal vaccines, as these individuals are at increased risk for pneumococcal disease. In addition, some adults aged 19 to 64 years with certain medical conditions should receive the vaccine, such as chronic illnesses of the heart, liver, kidney, or lung, as well as conditions that weaken the immunize system, such as HIV/AIDS or cancer.25

In 2016, vaccination coverage among this group was 66.9%.26 A meta-analysis of 22 studies in adults found that the risk of invasive pneumococcal disease (and to a lesser extent, all-cause pneumonia) is reduced by pneumococcal vaccination, and a randomized, placebo-controlled study showed a 63.8% reduction in pneumococcal pneumonia in group of institutionalized elderly patients. A reduction in the incidence of all cases of bacteremic and nonbacteremic pneumococcal pneumonia was shown in adults older than 50 years in a 3-year cohort study.27

Measles, Mumps, and Rubella

The MMR recommendations can be confusing. The ACIP recommendations state that people born before 1957 are generally considered to be immune to measles and mumps.28 Adults born in 1957 or later should have documentation of 1 or more doses of the MMR vaccine unless they have a medical contraindication or evidence of immunity. Other guidelines regarding the MMR vaccine concern the patient’s age, occupation, and what type of vaccine they may have received earlier in life. The ACIP states that people vaccinated before 1980 with either inactivated mumps vaccine or mumps vaccine of an unknown type who are at high risk for mumps infection should be considered for revaccination.28

Rubella immunity should be determined for women of child-bearing age, according to the ACIP. The recommendations state that pregnant women should have an MMR vaccine upon completion or termination of the pregnancy and before leaving the hospital.28

Tetanus-Diphtheria and Tetanus-Diphtheria-Acellular Pertussis

The ACIP recommends all adults to get the Td vaccine with boosters every 10 years.28 People 11 years of age or older who have not received the Tdap vaccine, or with an unknown status, should receive 1 dose of Tdap followed by a Td booster every 10 years, the guidelines state.

The CDC reported in the 2016 vaccine surveillance that the percentage of adults who said they received any tetanus type vaccination during the past 10 years, for adults 19 years of age and older, was 62.2%. When broken down further by age group, the number was 62.8% for adults ages 19 to 49 years, 64.2% for adults ages 50 to 64, and 58.0% for adults 65 years of age and older. Researchers also assessed Tdap vaccination and found that coverage in the past 10 years was 26.6%, 28.0%, and 20.4%, in the consecutive age groups.26

Varicella

The ACIP recommends a 2-dose varicella vaccination in healthy adults without a clinical history of varicella or evidence of varicella immunity.28 Those at high risk for exposure to or transmission of the virus should take special note of the recommendations.

The Significance of Age

Vulnerability to infection increases with age and comorbidities such as pulmonary disease, diabetes, asthma, or heart disease. Pneumococcal influenza vaccines are estimated to prevent thousands of deaths each year, yet the vaccination rate among adults 65 years of age and older was only 66.7% in 2015, according to CDC surveillance.29

Vaccination rates are discouragingly low for herpes zoster. In fact, among adults 60 years of age and older, the herpes zoster vaccination rates have been even lower than that of the influenza and pneumococcal vaccines. Just 27.9% of the mentioned age group received the vaccine in 2014.14 To restate the magnitude of this infection, it has been reported that the overall incidence of herpes zoster is 2.0 to 4.6 cases per 1000 person-years; but it increases dramatically with age to 10.0 to 12.8 per 1000 person-years among individuals who are ages 80 and older. Similarly, the incidence of postherpetic neuralgia also increases with age, compounding this problem.30

Despite ACIP recommendations, vaccination coverage rates among high-risk adults 65 years of age or older have also remain low.15 In the 2012 to 2013 season among adults ages 18 to 64 years with 1 or 2 high-risk conditions, the overall influenza vaccine coverage was only 49.5% and 59.5%, respectively.15

The need for increasing vaccination adoption comes dramatically into focus when considering the challenge presented by the aging population that currently exists in most developed countries. Although many vaccines are less effective in the elderly, experts emphasize that immunization remains an efficient means of preventing infectious diseases in the older population.31

Steps to Bolster Adult Vaccination

To successfully implement more comprehensive, widespread, and successful adult immunization programs, stakeholders will need to overcome many hurdles. Currently, there are many barriers including cost, a lack of knowledge and awareness, missed opportunities, and operational or systemic barriers.32 Research has shown that healthcare providers may prioritize some vaccines over others, and they sometimes rank vaccines below other preventive services. The investigators wrote that with many competing demands in primary care practice, physicians’ perception of immunization importance has major implications for vaccine delivery.33

Patients often do not know they need vaccinations, so they do not ask for them. Some patients are not aware of the benefits associated with adult immunization or that they might need booster doses.34 Research has shown that many healthcare providers (HCPs) do not know what the ACIP adult immunization recommendations are and are not aware of the many variations in recommendations due to age considerations and patients’ comorbidities. One survey revealed that just 60% of physicians and 56% of physician assistants, nurse practitioners, and registered nurses reported using official guidelines to inform their decisions regarding adult immunizations.35

Myths and fears of vaccines abound, and worry over adverse effects are common reasons why adults avoid immunization.27 HCPs and patients face additional systemic and operational barriers such as vaccine storage difficulties and lack of current, easily accessed immunization records.27

The Important Role of HCPs

To increase adult vaccination rates, HCPs, including pharmacists in retail and health system settings, must not only be knowledgeable about the use of vaccines, but they must also take on the role of advocates for achieving set vaccination goals (eg, Healthy People 2020). It has been shown that patients are strongly influenced by their HCPs; therefore, any vaccination recommendations they make are going to be associated with better patient compliance.15 If HCPs do not discuss vaccination with patients, this leaves a giant gap for vaccine noncompliance to fill. In fact, most consumers in 1 study indicated they were likely to receive a vaccine if their healthcare professional recommended it. At the same time, more than half of the HCPs in the study admitted that they did not always discuss vaccine recommendations.35

Guidelines from the American Society of Health-System Pharmacists (ASHP) highlight the need for HCPs to develop strategies and approaches for patient counseling that take into consideration their individual situation and their specific concerns.9 Online tools and free apps are available to assist HCPs in screening patients and recommending vaccines (eg, www.vaccines.gov/more_info/features/healthmapvaccinefinder.html). It should be emphasized that HCPs themselves have a professional responsibility to adhere to their own personal vaccinations to promote their own health as well as protecting the health of patients and colleagues.9 HCPs must set an example for the entire community in terms of vaccination advocacy and adherence.

Change of Venue

One approach to bridging the gap between where adult vaccination rates should be and where they are, is the use of nontraditional vaccination delivery sites with special walk-in service and extended hours.36-38 Pharmacies are uniquely positioned to offer immunization services that can successfully increase the number of adult vaccinations administered.36-38 Data indicate an increase in adult vaccination when pharmacy-based immunization programs offer expanded hours, while ease of access and convenience are a big factor for adults receiving immunizations.38

Influenza vaccines are the most commonly given vaccine in pharmacies, with nearly half of all influenza vaccines being administered in nonmedical setting in recent years. However, community pharmacies are underutilized as a site of delivery for many other adult vaccinations such as the pneumococcal inoculation, herpes zoster, and Tdap.36

Systemic Obstacles and Potential Solutions

In a study of recommendations for implementing a vaccine benefit, investigators found that, by and large, programs lack data sharing and reporting mechanisms.39 It has been suggested, therefore, that the electronic medical records be used for two-way communication between pharmacists and primary care providers.39 For example, with a strengthened communications between physicians and pharmacies, individuals can receive their first injection in a vaccination series at the physician’s office, followed by subsequent injections at the pharmacy. Experts have also suggested that pharmacies should be included in other report solutions, including state health information exchanges and immunization registries, as this could increase coordinated care between pharmacists and primary care providers.39

The Patient Protection and Affordable Care Act requires that qualified private health insurance policies provide full reimbursement for recommended vaccines with no out-of-pocket costs for patients. Medicare and Medicaid also pay for some vaccines, depending on the patient’s plan.

ASHP and others emphasize the advocacy role of pharmacists, stating that, whenever necessary, health system pharmacists should advocate reimbursement for needed immunizations that are not covered by insurance as a cost-effective preventive measure. Pharmacists can still connect patients without insurance coverage to options for vaccinations, such as charging a small out-of-pocket payment or referring them to a free vaccination program.9

Nonprofit Programs, Building Partnerships

More public education efforts should be put in place with specific messaging to target at-risk and nonadherent groups, including age-based information and education to dispel myths surrounding vaccines. Nonprofit organizations can support public policy by communicating the benefits of vaccination through social media, public service announcements, and public events. These groups provide a key connection between the scientific community and individuals.27 Pharmacists can advocate for vaccinations by organizing and participating in community-based efforts.9 They can form partnerships with like-minded groups to promote vaccination. Resources for these and other efforts include the Immunization Action Coalition and the National Coalition for Adult Immunization. The success of pharmacy vaccinations has led the CDC to recommend “expanding access through nontraditional settings, for example, pharmacy, workplace, and school venues for vaccination to reach individuals who may not visit a traditional provider during the flu season.”37

Components of a Vaccine Administration Program

To effectively administer a vaccine program, the correct protocol and infrastructure must be in place. Storage and disposal of injection supplies, particularly with regard to disposal of used needles, is crucial.9 Resources for setting up an immunization program are available from the American College of Physicians (www.acponline.org) and from the CDC (www.cdc.gov/vaccines). Pharmacists and their staff must be fully immunized.

Professional guidelines and legal regulations guide vaccine administration.9 Each state’s laws and regulations governing pharmacy practice determine the pharmacist’s authority. Forging partnerships with state boards of pharmacy, health departments, and pharmacy associations can help groups develop more streamlined and simplified processes for implementing pharmacy-based immunization services. Pharmacists should be trained in all aspects of vaccine administration, in according to their individual state laws.9 They should also have access to current immunization references (eg, the CDC’s National Immunization Program publications, including Epidemiology and Prevention of Vaccine-Preventable Diseases, called the “Pink Book”), and evolving guidelines and recommendations.9

Conclusions

The underuse of widely available vaccines has created an opportunity for pharmacists to play a key role in improving immunization rates and advancing public health. Community pharmacy-based vaccination services have already increased the number of immunization providers and the number of sites where patients can receive immunizations. There are still challenges ahead, however, and more work needs to be done to identify opportunities and challenges for improving the infrastructure of vaccine delivery.

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