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. Author manuscript; available in PMC: 2022 Dec 1.
Published in final edited form as: Am J Prev Med. 2021 Feb 23;60(5):692–700. doi: 10.1016/j.amepre.2020.11.013

Availability of Adult Vaccination Services by Provider Type and Setting

Charleigh J Granade 1,2, Russell F McCord 3,4, Alexandra A Bhatti 3,4,5, Megan C Lindley 1
PMCID: PMC9713581  NIHMSID: NIHMS1836975  PMID: 33632648

Abstract

Introduction:

Knowledge regarding the benefits for adult vaccination services under Medicaid’s fee-for-service arrangement is dated; little is known regarding the availability of vaccination services for adult Medicaid beneficiaries in MCO arrangements. This study evaluates the availability of provider reimbursement benefits for adult vaccination services under fee-for-service and MCO arrangements for different types of healthcare providers and settings.

Methods:

A total of 43 Medicaid directors across the 50 U.S. states and the District of Columbia participated in a semistructured survey conducted from June 2018 to June 2019 (43/51). The frequency of Medicaid fee-for-service and MCO arrangements reporting reimbursement for adult vaccination services by various provider types and settings were assessed in 2019. Elements of vaccination services examined in this study were vaccine purchase, vaccine administration, and vaccination-related counseling.

Results:

Under fee-for-service, 41 Medicaid programs reimburse primary care providers for adult vaccine purchase (41/43); fewer programs reimburse vaccine administration and vaccination-related counseling (33/43 and 30/43, respectively). Similar results were observed for obstetricians–gynecologists, nurse practitioners, and pharmacies. Although 24 fee-for-service (24/43) and 23 MCO (23/34) arrangements cover adult vaccination services in most settings, long-term care facilities have the lowest reported reimbursement eligibility.

Conclusions:

In most jurisdictions, vaccination services for adult Medicaid beneficiaries are available for a variety of healthcare provider types and settings under both fee-for-service and MCO arrangements. However, because provider reimbursement benefits remain inconsistent for adult vaccination counseling services and within long-term care facilities, access to adult vaccination services may be reduced for Medicaid beneficiaries who depend on these resources.

INTRODUCTION

In 2010, the Patient Protection and Affordable Care Act expanded Medicaid benefits eligibility to include childless adults with incomes ≤138% of the federal poverty level.1 Consequently, the number of Medicaid-eligible individuals increased by nearly 15 million2; it is estimated that nearly 38 million American adults currently receive health care through Medicaid.3 Because many aspects of Medicaid implementation are determined at the state level, substantial variability in access to many medical services exists across the U.S.4

The Advisory Committee on Immunization Practices recommends 13 vaccines for adults aged ≥19 years on the basis of age, medical condition, and other risk factors, including annual influenza vaccination for all adults.5 Adults can receive vaccinations from a multitude of healthcare providers6; receipt of vaccination through pharmacies or community health centers is becoming increasingly common.7–10 For adult Medicaid enrollees, the settings where vaccines may be administered vary by program. In Medicaid programs that permit vaccination services outside of primary care physician offices, access to preventive services through Federally Qualified Health Centers or retail clinics increased after Medicaid expansion.4 The use of nontraditional health settings such as pharmacies has been shown to increase adult vaccination coverage for influenza and zoster vaccines.11 Still, challenges regarding access to primary care and confusion around benefits coverage has resulted in adult Medicaid beneficiaries overutilizing some healthcare settings such as emergency departments.12 Therefore, beneficiaries in programs with fewer settings available for adult vaccination services likely have a lower vaccination coverage, especially those without a medical home.13

Previous assessments of adult Medicaid vaccination policy are dated and limited to fee-for-service (FFS) arrangements.14–16 However, MCOs have been available in the U.S. for decades, and recent changes to their scope of services have increased their use by Medicaid programs.17 As of 2017, more than two thirds (69.3%) of all Medicaid beneficiaries were enrolled in managed care arrangements.18 In jurisdictions that expanded Medicaid, newly eligible adults now represent most of the beneficiaries enrolled in MCOs.19 Managed care programs differ from traditional FFS because these organizations contract with Medicaid programs to provide health benefits and services to Medicaid beneficiaries in return for capitated per-member-per-month payments.20 Provider payment arrangements for services such as adult vaccination are therefore determined by contract and vary by program and plan as well as by provider type and healthcare setting.21

This study seeks to provide an updated landscape of adult Medicaid vaccination policy through the examination of provider reimbursement benefits for adult vaccination services across the 50 U.S. states and District of Columbia. Findings regarding adult vaccination benefits coverage have already been presented22; the primary focus of this paper is to evaluate reimbursement under FFS and MCO arrangements by the type and number of individual providers covered as well as by the healthcare settings where vaccines may be administered.

METHODS

This study was completed between April 2018 and June 2019. A public domain document review was first conducted in April 2018 and again in April 2019; a survey assessing adult vaccination policies for Medicaid FFS and MCO arrangements was administered from June 2018 to June 2019. Data were analyzed in 2019. Detailed methods of the document review are described elsewhere.22

The survey was jointly developed by the Public Health Law Program and the Immunization Services Division of the Centers for Disease Control and Prevention. This project was determined to be research not involving human subjects and thus did not require IRB approval.

Study Sample

Medicaid directors were identified and recruited using the National Association of Medicaid Directors online directory.23 Each director was contacted by e-mail and received an introductory letter, a public domain document review summary for their state, and an advanced copy of the survey instrument. Nonresponding Medicaid directors were sent up to 5 additional e-mails. Both Medicaid directors and individuals delegated to respond on behalf of the director were permitted to participate in the survey.

Respondents were asked to participate in a 60-minute semi-structured telephone survey. All surveys were recorded and transcribed, with participant consent obtained at the start of the survey. For Medicaid programs that were unable to participate in the telephone survey, respondents could respond by e-mail instead. The survey questions and probing used for the telephone survey and written responses were identical.

To reflect known differences across Medicaid programs, slightly different survey instruments were distributed to programs on the basis of whether the jurisdiction had implemented Medicaid expansion since 2010, which service arrangements were in place (FFS, MCO, or both), and whether the program had declared eligibility for Section 4106 incentive payments by covering all Advisory Committee on Immunization Practices–recommended vaccines with no cost sharing for both traditionally eligible and expansion Medicaid populations.24

Measures

To determine vaccination services benefits for adult Medicaid beneficiaries, provider reimbursement eligibility was evaluated by the type and number of individual providers and settings. Because FFS and MCO reimbursement methodologies are disparate, benefits eligibility was assessed differently. Provider reimbursement benefits under FFS were assessed for 3 elements of service: vaccine purchase, vaccine administration, and vaccination-related counseling services. Because separate Current Procedural Terminology codes inclusive of vaccination-related counseling services are presently only available for children, reimbursement for adult vaccination-related counseling was assessed more broadly. Specifically, any program reporting reimbursement benefits for adult vaccination-related counseling for listed providers and within setting types were considered to cover this element of vaccination services even if not separately reimbursed.

Because information regarding the health services provided under MCO arrangements is based on individual contractual agreements between Medicaid programs and each MCO plan, evaluation of reimbursement benefits for adult immunization was limited to the general provision of these services for Medicaid managed care populations rather than by individual elements of service. In addition, provider types considered in network under the MCO arrangement were assessed.

Reimbursement eligibility was evaluated for 4 major healthcare provider types: primary care physician, obstetrician–gynecologist (OB-GYN), pharmacy, and nurse practitioner; eligibility of other nonphysician providers was also assessed (because healthcare provider definitions differ across states, OB-GYNs were assessed separately from primary care providers). The settings where providers may administer adult vaccinations also vary by program; provider reimbursement under the FFS arrangement was assessed in the following healthcare settings identified by the authors as potential complements to primary care: hospital outpatient, long-term care facilities, state/local public health departments (HDs), specialty sexually transmitted disease (STD)/Title X clinics, maternal and child health clinics, mobile clinics, community-based organizations (i.e., Federally Qualified Health Centers), and community settings such as pharmacies located within grocery stores.

Statistical Analysis

To assess adult Medicaid beneficiary access to vaccination service benefits, the frequency of provider types and settings eligible to receive provider reimbursement for adult vaccination services was calculated for each participating Medicaid program. Because most Medicaid programs do not separately reimburse vaccination-related counseling under FFS, provider reimbursement for vaccination services was defined as adult vaccine purchase and vaccine administration only.

RESULTS

A total of 45 (88.2%) of 51 Medicaid programs responded to the survey. Of those, 35 completed the telephone survey (35/45), and 10 submitted responses electronically (10/45). Surveys from 44 programs were complete and were included in analyses. Of the programs that responded, 34 reported the use of MCO arrangements. With the exception of Tennessee, which is 100% MCO, all responding Medicaid programs reported the use of FFS arrangements (43/44). The remaining 6 programs either did not respond or declined to participate in the survey.

A total of 22 Medicaid programs reimburse all the 4 major provider types for adult vaccination services under the FFS arrangement. Reimbursement of adult vaccination services is restricted to ≤2 providers in 5 programs. In California, although all provider types are eligible for reimbursement for vaccine purchase, nurse practitioners and pharmacies are not reimbursed for vaccine administration. A total of 4 programs reported limiting reimbursement for vaccine administration to pharmacy providers only (Georgia, Massachusetts, Minnesota, and West Virginia).

The number of healthcare settings where adult vaccinations may be administered and that are eligible for reimbursement are described in Figure 1 (FFS) and Figure 2 (MCO). Most Medicaid FFS arrangements reimburse for vaccine purchase and administration in ≥3 setting types (35/43), with 24 programs reimbursing adult vaccination services in 7–8 settings (24/43) (Figure 1). For programs with MCO arrangements, findings regarding settings were similar to those for FFS (Figure 2). Managed care arrangements in 23 programs reimburse adult vaccination services provided in 7–8 settings (23/34), and only 5 programs (Florida, Illinois, Minnesota, West Virginia, and Texas) limit reimbursement to ≤4 settings.

Figure 1. The number of settings where vaccination services benefits are available under FFS, by program.

Figure 1.

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Note: Healthcare settings are defined here as hospital outpatient, long-term care facilities, state/local public health departments, specialty STD and/or Title X clinics, maternal and child health clinics, mobile clinics, community-based organizations, and community settings. Because vaccination-related counseling services are not separately reimbursed for the majority of Medicaid programs, reimbursement eligibility for adult vaccination services by setting is restricted to adult vaccine purchase and vaccine administration. RI Medicaid does not reimburse for vaccine purchase; therefore, only reimbursement eligibility for vaccine administration by setting was assessed. CT, DE, IL, MD, and VA Medicaids do not reimburse for vaccine administration, and GA, FL, and WV Medicaids only reimburse pharmacists; therefore, programs were excluded because they did not meet adult vaccination services criteria. Reimbursement eligibility for vaccine purchase and administration is not identical across all settings in CA, ME, NE, OR, and PA Medicaid; therefore, only vaccine purchase reimbursement eligibility by setting was assessed. Minnesota Medicaid reimburses vaccine purchase in all settings; however, only long-term care facilities are eligible for reimbursement for vaccine administration. Data missing for vaccine administration by setting for LA Medicaid; therefore, only reimbursement eligibility for vaccine purchase by setting was assessed.

AK, Alaska; AL, Alabama; AR, Arkansas; AZ, Arizona; CA, California; CO, Colorado; CT, Connecticut; DC, District of Columbia; DE, Delaware; FFS, fee-for-service; FL, Florida; GA, Georgia; HI, Hawaii; IA, Iowa; ID, Idaho; IL, Illinois; IN, Indiana; KS, Kansas; KY, Kentucky; LA, Louisiana; MA, Massachusetts; MCO, managed care organization; MD, Maryland; ME, Maine; MI, Michigan; MN, Minnesota; MO, Missouri; MS, Mississippi; MT, Montana; NC, North Carolina; ND, North Dakota; NE, Nebraska; NH, New Hampshire; NM, New Mexico; NV, Nevada; OH, Ohio; OK, Oklahoma; OR, Oregon; PA, Pennsylvania; RI, Rode Island; SC, South Carolina; SD, South Dakota; STD, sexually transmitted disease; TN, Tennessee; TX, Texas; UT, Utah; VA, Virginia; VT, Vermont; WA, Washington; WI, Wisconsin; WV, West Virginia; WY, Wyoming.

Figure 2. The number of settings where vaccination services benefits are available under MCO, by program.

Figure 2.

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Note: Healthcare settings are defined here as hospital outpatient, long-term care facilities, state/local public health departments, specialty STD and/or Title X clinics, maternal and child health clinics, mobile clinics, community-based organizations, and community settings. Owing to the individualized, contractual relationship between MCOs and the programs, evaluation of reimbursement benefits for adult immunization services under the MCO arrangement was assessed differently from that under the FFS arrangement; this is limited to the general provision of these services only. Because of this, no service-specific information is available. AL, AK, CT, ID, ME, MT, OK, SD, VT, and WY Medicaids are under 100% FFS arrangement. Data are missing for KY, MA, and VA MCO arrangements.

AK, Alaska; AL, Alabama; AR, Arkansas; AZ, Arizona; CA, California; CO, Colorado; CT, Connecticut; DC, District of Columbia; DE, Delaware; FFS, fee-for-service; FL, Florida; GA, Georgia; HI, Hawaii; IA, Iowa; ID, Idaho; IL, Illinois; IN, Indiana; KS, Kansas; KY, Kentucky; LA, Louisiana; MA, Massachusetts; MCO, managed care organization; MD, Maryland; ME, Maine; MI, Michigan; MN, Minnesota; MO, Missouri; MS, Mississippi; MT, Montana; NC, North Carolina; ND, North Dakota; NE, Nebraska; NH, New Hampshire; NM, New Mexico; NV, Nevada; OH, Ohio; OK, Oklahoma; OR, Oregon; PA, Pennsylvania; RI, Rode Island; SC, South Carolina; SD, South Dakota; STD, sexually transmitted disease; TN, Tennessee; TX, Texas; UT, Utah; VA, Virginia; VT, Vermont; WA, Washington; WI, Wisconsin; WV, West Virginia; WY, Wyoming.

A total of 41 Medicaid programs reimburse primary care providers and OB-GYNs for adult vaccine purchase under FFS (Figure 3). The 2 remaining programs do not reimburse for vaccine purchase (Rhode Island) or only reimburse pharmacy providers (Florida). Although reimbursement is limited to physician, nurse practitioner, or pharmacy providers in 18 FFS arrangements, 24 state Medicaid programs also reimburse other nonphysician provider types. Eligible nonphysician providers include physician assistants (15/43), midwives (6/43), providers where vaccination is included as part of their scope of practice (3/43), naturopaths (2/43), and emergency medical technicians (1/43).

Figure 3. Vaccination services benefits for adult Medicaid beneficiaries enrolled under FFS, by provider type.

Figure 3.

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Note: Because the following Medicaid programs did not participate in the semistructured survey, data from Arkansas, Iowa, New Jersey, North Carolina, and Utah vaccination services benefits are not represented.

FFS, fee-for-service; OB-GYN, obstetrician–gynecologist.

With respect to adult vaccine administration, Medicaid FFS arrangements most frequently reimburse primary care providers (33/43), OB-GYNs (32/43), pharmacies (31/43), and nurse practitioners (29/43). For pharmacies, nearly half of FFS arrangements report reimbursement using a dispensing fee, a professional fee intended to cover the cost of drug transfer to a patient (15/31). Additional nonphysicians eligible for reimbursement for adult vaccine administration are physician assistants (8/43), midwives (4/43), naturopaths (2/43), and emergency medical technicians (1/43). FFS arrangements in 4 Medicaid programs restrict provider reimbursement benefits for vaccine administration to pharmacies only (4/43).

A total of 30 Medicaid FFS arrangements reimburse primary care providers for adult vaccination-related counseling (30/43). Among those, 25 programs reported that their FFS arrangements reimburse for adult vaccination counseling as part of the evaluation and management payment (25/30). In Oklahoma, providers may increase their reimbursement using multiple evaluation and management codes in addition to administration codes to reflect services above and beyond those usually provided in vaccination. Providers in Kentucky may receive supplemental reimbursement for counseling using a time-based billing code to account for additional time spent with the patient.

In general, MCO arrangements in nearly all Medicaid programs consider primary care providers and OB-GYNs as in network (33/34), followed by nurse practitioners (32/34), and pharmacies (29/34). In MCO arrangements where pharmacist providers are not considered in network, provided reasons include FFS-only carve outs (in Missouri) or the use of an experimental patient-centered medical home model for medication therapy management (in Tennessee). For Medicaid programs that contract with a larger number of MCOs, survey respondents reported that there is likely great variability between MCOs regarding which provider types are considered in network.

Most Medicaid programs reimburse providers for adult vaccine purchase in the hospital outpatient setting under FFS (39/43) (Figure 4). A total of 40 FFS arrangements reimburse vaccine purchase in long-term care facilities; however, only 26 report reimbursing providers for this service separately from a bundled facility per-day rate (26/40). In Florida, provider reimbursement is limited to pharmacy services offered in the residential facility only.

Figure 4. Vaccination services benefits for adult Medicaid beneficiaries enrolled under FFS or MCO, by setting type.

Figure 4.

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Note: Presented data represents 43/51 participating FFS and 34/51 participating MCO arrangements. Because the following Medicaid programs did not participate in the semistructured survey, data from Arkansas, Hawaii, Iowa, New Jersey, North Carolina, and Utah vaccination services benefits are not represented. Evaluation of reimbursement benefits for adult immunization under MCO arrangement was limited to the general provision of vaccination services rather than by individual elements of service (vaccine purchase, vaccine administration, and vaccination-related counseling). FFS, fee-for-service; MCO, managed care organization; STD, sexually transmitted disease.

In the settings where vaccines may be administered, 30 Medicaid FFS arrangements (30/43) reimburse providers for adult vaccine administration in hospital outpatient and maternal and child health clinic settings. Providers are also eligible for reimbursement in STD/Title X clinics (29/43) and state/local public HDs and community-based organizations (both 28/43).

With respect to reimbursement for vaccination-related counseling, programs reported that providers are eligible for reimbursement benefits in hospital outpatient settings (28/43), maternal and child health clinics (27/43), and STD/Title X clinics (26/43). State/local HDs, community-based organizations, and long-term care facilities are reimbursed for adult vaccination counseling in 25 of 43 state FFS arrangements. In Ohio, minute clinics and ambulatory care may receive reimbursement under FFS, but counseling is not reimbursed if provided in a nurse-only clinic.

A total of 29 Medicaid programs (29/34) reported that their MCOs reimburse for adult vaccination services provided in the hospital outpatient setting, followed by 27 programs that cover vaccination in maternal and child health clinics (Figure 4). MCO arrangements also reimburse state/local HDs, STD/Title X clinics, mobile clinics, community-based organizations (all 26/34), and community settings (25/34). Only 24 of 34 programs reported that their MCO arrangements reimburse adult vaccination services within long-term care facilities.

DISCUSSION

Findings from this survey demonstrate that most Medicaid programs provide reimbursement benefits for adult vaccine purchase and administration for a variety of provider types and within many healthcare settings. Separate provider benefits for adult vaccination-related counseling services remain absent in most programs. Therefore, current reimbursement benefit policies pertaining to adult immunization services do not encompass all associated costs of adult immunization and consequently may negatively affect providers’ willingness to vaccinate adults covered under Medicaid.

After Medicaid expansion, concerns regarding provider shortages generated increased interest in expanding the scope of practice for nonphysician practitioners.25–27 In this survey, most Medicaid programs reported that nurse practitioners and pharmacists are eligible to receive reimbursement for adult vaccination services under either FFS or MCO arrangements. However, many programs continue to implement either reduced or restricted practice laws for nonphysician healthcare providers, which may limit reimbursement amounts and/or eligibility for reimbursement28,29 In addition, although community pharmacies are integral to increasing access to vaccination in medically underserved areas or rural settings experiencing significant provider shortages,30,31 recognition of pharmacists as vaccination providers and expansion of the scope of practice has been challenging.32 Because they routinely store medications onsite, pharmacies are well equipped to stock vaccines, particularly those requiring frozen storage; programs that do not reimburse vaccination by pharmacists limit an important access point for patients served by physician practices that cannot stock all recommended vaccines. Reduced scope of practice restrictions coupled with a continued expansion of provider reimbursement benefits could potentially facilitate higher adult vaccination coverage through increasing access to immunization services.9,33,34

Across Medicaid programs, healthcare provider reimbursement for adult vaccination counseling services remain ancillary to both vaccine purchase and vaccine administration benefits; separate reimbursement for adult vaccination–related counseling is currently unavailable in most programs. A recent study evaluating the costs associated with vaccinating adult patients found that regardless of specialty, providers experience resource deficits when patients refuse vaccination because there is no separately identifiable reimbursement for vaccination counseling.35 In this survey, Medicaid programs confirmed that reimbursement benefits under FFS for adult vaccination counseling are bundled with evaluation and management billing fees, vaccine purchase codes, or vaccine administration codes. Under Kentucky and Oklahoma Medicaid FFS arrangements, additional reimbursement for adult vaccination counseling is available but requires submission of multiple evaluation and management codes that may be cumbersome to providers. Continued use of bundled counseling codes may therefore disincentivize providers from participating in adult vaccination services owing to inadequate provider compensation. Implementation of revised time-based billing rules for patient evaluation and management will need to be monitored to determine their impact on provider payment for vaccination counseling.36

Irrespective of payer type, reimbursement for the provision of vaccination services in the pharmacy setting is complex37,38 and has been cited as a barrier to vaccine administration by pharmacists.9 For example, some programs permit pharmacists to use the FFS fee schedule for reimbursement only if they are a Medicaid recognized provider type.39 Otherwise, programs may reimburse using a dispensing fee, which varies by pharmacy type, prescription volume, drug type,40 and state.41 In this survey, nearly half of the participating Medicaid programs reported that pharmacies under their FFS arrangement are reimbursed using a dispensing fee. For MCO arrangements, pharmacy benefits may be carved in (included) or carved out (excluded) and included under FFS only. For programs where these services are included, previous work shows that reimbursement for vaccination often varies by contract,40 consistent with these findings. Consequently, inconsistencies in pharmacy reimbursement processes for both FFS and MCO arrangements likely result in under-reimbursement for vaccination services across pharmacy settings and may reduce beneficiary access to vaccination to the extent that they discourage pharmacists from vaccinating Medicaid enrollees.

The challenges regarding Medicaid reimbursement policies for long-term care facilities through the use of per-day rates are well known.42–44 Although per-day rates incorporate a litany of provided medical services, reimbursement amounts are not necessarily tied to actual costs for a long-term care facility but rather by what a program can pay.42 In this survey, separate reimbursement benefits for adult vaccination services provided in long-term care facilities remain limited for both FFS and MCO arrangements. Because Medicaid reimbursement policies for adult vaccines purchased or administered by long-term care facilities rely on per-day rates, reimbursement amounts are likely not enough to cover all costs associated with this service. Because Medicaid is currently the largest payer of long-term services and support, the current reimbursement policy may result in the underimmunization of Medicaid patients receiving long-term facility care.45,46

Limitations

This survey has the following limitations: first, because the authors were unable to obtain responses from all the 51 Medicaid jurisdictions, results do not describe provider eligibility benefits for adult immunization services for all providers practicing within the U.S. Second, given the individualized, contractual relationship between MCOs and the programs, the survey question regarding MCO arrangement benefits for adult immunization services was worded differently from the equivalent question for FFS. Specific information regarding reimbursement benefits for vaccine purchase, vaccine administration, and vaccination-related counseling was not collected. Third, because Medicaid policies change frequently, the information collected from respondents may no longer be current.

CONCLUSIONS

This study provides an updated landscape of provider reimbursement benefits and policy across Medicaid programs after the Affordable Care Act implementation. Irrespective of FFS or MCO arrangement, eligibility for reimbursement benefits for adult vaccine purchase and vaccine administration are permitted for a variety of healthcare providers and settings; however, separate reimbursement for vaccination-related counseling remains largely absent. In addition, reimbursement benefits remain inconsistent for pharmacists and within long-term care facilities; therefore, access to adult immunization services may be reduced for Medicaid beneficiaries who depend on these resources. Future research could examine the correlation between vaccination services availability and vaccination coverage among adult Medicaid beneficiaries. Policies that address observed Medicaid provider reimbursement disparities for adult immunization services may further encourage efforts aimed at increasing adult vaccination coverage in the U.S.

ACKNOWLEDGMENTS

The findings and conclusions of this report are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention (CDC).

This work was funded by CDC. This project was also supported in part by an appointment to the Research Participation Program for CDC, National Center for Immunization and Respiratory Diseases, and Immunization Services Division, administered by the Oak Ridge Institute for Science and Education through an agreement between the U.S. Department of Energy and CDC.

Footnotes

No financial disclosures were reported by the authors of this paper.

REFERENCES

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