Quality Management Medical Study

A Report on the
Immunization Status of AHCCCS Members
2 Years of Age for Contract Year 2001
(October 1, 2000, through September 30, 2001)

Produced By:

The Office of Medical Management
March 2002

AHCCCS ANNUAL IMMUNIZATION ASSESSMENT
CONTRACT YEAR 2001
TABLE OF CONTENTS

EXECUTIVE SUMMARY.…………………………………..........................................................ii
I. INTRODUCTION…………………………………………………………….................................1
II. PURPOSE............................…………………………………………………………………….4
III. IMMUNIZATION RECOMMENDATIONS AND QUALITY INDICATORS………..………5
♦ Primary Quality Indicators
♦ Additional Quality Indicators
IV. METHODOLOGY…....…......................………………………………………………………6
♦ Study Sample
♦ Assessment Tool
♦ Data Collection
♦ Data Validation
♦ Data Analysis
V. RESULTS…………………..........………………………….………………………………….10
♦ Medicaid (Title XIX)
♦ KidsCare (Title XXI)
VI. ANALYSIS…………………………………………………………………………………...13
VII. CONCLUSIONS AND RECOMMENDATIONS………….........................…………………14
VIII. REFERENCES........................................................................................................................17
IX. TABLES
X.

APPENDICES

AHCCCS Annual Immunization Assessment, Contract Year 2001

i

AHCCCS ANNUAL IMMUNIZATION ASSESSMENT
CONTRACT YEAR 2001
(October 1, 2000, to September 30, 2001)
EXECUTIVE SUMMARY
This is the ninth annual assessment of immunization completion rates among selected 2-year-old
children enrolled in the Arizona Health Care Cost Containment System (AHCCCS). This study
evaluated the immunization status of children eligible under Medicaid (Title XIX of the Social
Security Act) and KidsCare (Title XXI, the State Child Health Insurance Program) during the
contract year from October 1, 2000, to September 30, 2001.
Monitoring of immunization rates is critical to identifying undervaccinated populations and
increasing coverage levels, in order to prevent circulation of viruses and bacteria that cause many
childhood diseases.
The Centers for Disease Control and Prevention (CDC) recommends immunizing children for 12
preventable diseases. Ten of the 12 immunizations are discussed in this report. They include
diphtheria, tetanus, and acellular pertussis (DTaP) vaccine, inactivated poliovirus (IPV) vaccine,
measles, mumps and rubella (MMR) vaccine, Haemophilus influenza type b (Hib) vaccine, hepatitis
B virus (HBV) vaccine, and varicella zoster virus (VZV) vaccine. Pneumococcal conjugate vaccine
(PCV) was not included in this study because of its recent introduction, and because manufacturing
delays limited availability of the vacine during the study period. Hepatitis A immunization also was
not studied because it is not recommended as a routine vaccination in all areas of the state.
Methodology
AHCCCS identified a representative random sample of children within each contracted Health Plan
(Contractor), stratified by county. The final sample size included 5,480 children (Medicaid and
KidsCare combined) whose second birthdays occurred during the study period. Data initially was
obtained from the Arizona State Immunization Information System (ASIIS), an automated registry.
When an incomplete record or no record was found in ASIIS, that case was sent to the appropriate
Contractor for further data collection. An external quality review organization (EQRO) was utilized
for data entry, and to aggregate and validate results.
Overall Findings
For all but one individual vaccination, rates of completed immunizations for the combined Medicaid
and KidsCare samples improved from the previous contract year. The only rate for the combined
population that did not increase in the most recent year, DTaP, was only 0.2 percent below last year's
level. Combined rates of completion for two series of vaccinations also improved. The five-antigen
series that includes DTaP, IPV, MMR, Hib and HBV showed the greatest improvement from the
previous year, increasing from 63.4 percent to 66.1 percent. It should be noted that the antigen-series
rates are not an average of the individual antigens, but a measurement of the number of children who
had all of the required immunizations.

AHCCCS Annual Immunization Assessment, Contract Year 2001

ii

AHCCCS goals for immunization completion rates in four categories (including the DTaP
immunization rate, which was within 0.2 percent of the AHCCCS goal) were met by the combined
population during contract year (CY) 2001. The following is a comparison of individual and antigenseries rates for all children included in the study in CYs 2000 and 2001 with AHCCCS goals.
COMBINED TWO-YEAR-OLD IMMUNIZATION RATES
(Medicaid and KidsCare Populations)
Immunization
(Doses)
All children,
CYE 2000
All children,
CYE 2001
AHCCCS
Goals*

DTaP
(4)

IPV
(3)

MMR
(1)

Hib
(2)

HBV
(3)

VZV
(1)

4:3:1
Series

4:3:1:2:3
Series

82.0%

87.9%

87.3%

82.8%

77.7%

71.9%

78.0%

63.4%

81.8%

88.5%

90.0%

83.4%

80.4%

78.5%

79.1%

66.1%

82.0%

88.0%

90.0%

90.0%

87.0%

67.0%

82.0%

73.0%

Notes: The 4:3:1 Series is four doses of DTaP, three doses of IPV, and one MMR dose.
The 4:3:1:2:3 Series is four doses of DTaP, three doses of IPV, one dose of MMR, two doses of Hib, and three doses of
HBV.
* AHCCCS goals are for Contract Year 2001.

The KidsCare Program has made great strides in reaching AHCCCS goals, even though it is
relatively new (the program was implemented November 1, 1998). Below is a comparison of
immunization completion rates between the KidsCare and Medicaid children included in the CY
2001 study.
COMPARISON OF KIDSCARE AND MEDICAID TWO-YEAR-OLD IMMUNIZATION RATES
Immunization
(Doses)
KidsCare
Medicaid

DTaP
(4)

IPV
(3)

MMR
(1)

HIB
(2)

HBV
(3)

VZV
(1)

4:3:1
Series

4:3:1:2:3
Series

82.5%
81.0%

89.3%
87.7%

90.2%
89.7%

83.0%
83.8%

79.9%
80.8%

79.9%
77.1%

80.1%
78.1%

67.0%
65.1%

Conclusion
Much of the improvement in immunization rates is due to the partnership among AHCCCS,
Contractor and providers. AHCCCS Contractors' outreach efforts have been successful in
encouraging families to complete immunizations for their children. Other activities that facilitate
access to services, such as providing transportation and assistance with scheduling appointments,
have contributed to the steady increase in AHCCCS immunization rates. In addition, collaboration
with the Arizona Department of Health Services (ADHS) Immunization Program Office, which
administers the state's Vaccines for Children (VFC) program and the ASIIS registry, has contributed
to improvement in immunization rates. Further efforts through The Arizona Partnership for
Immunization (TAPI), of which AHCCCS is a key member, have raised public awareness of the
importance of immunizations and provided a forum for many organizations to collaborate toward
a common goal.

AHCCCS Annual Immunization Assessment, Contract Year 2001

iii

Additionally, AHCCCS Contractors and community based organizations have been successful in
enrolling children into the KidsCare program. These outreach efforts are aimed at linking children
to health services, and likely contributed to immunization rates for KidsCare members that generally
were somewhat higher than rates for children enrolled under Medicaid.
AHCCCS Contractors have maintained or improved immunization rates despite a significant
increase in AHCCCS membership. Combined enrollment in the AHCCCS acute Medicaid and
KidsCare programs increased by 21 percent during CY 2001. Accordingly, the total sample for this
study increased 18.3 percent from the previous year.
AHCCCS has made substantial progress toward meeting the immunization goals of Healthy People
2000: National Health Promotion and Disease Prevention Objectives. These goals include a 90percent rate of immunization for all individual antigens and for the 4:3:1 combination. Goals
established for Healthy People 2010 are the same as the 2000 goals for individual antigens. Healthy
People 2010 also includes a goal of 80 percent for children ages 19-35 months who receive the
4:3:1:3:3 series of vaccines (four DTaP, three IPV, one MMR, three Hib and three HBV doses).
AHCCCS will continue to strive to meet these goals.
As AHCCCS immunization rates come closer to meeting Healthy People goals, it will become more
difficult to achieve significant improvement. Moreover, the study sample draws upon a new
population of 2-year-olds each year, rather than building on the successful efforts focused on the
previous group. This makes the task of improvement difficult and challenging each year.
Limited supplies of some vaccines also may affect the level of improvement in AHCCCS
immunization rates in the future. During this study period, manufacturing delays of DTaP vaccine
resulted in limited supplies and may have contributed to the lack of improvement in the completion
rate for this antigen. Shortages of certain vaccines are expected to continue into mid-2002 and may
affect future studies.
AHCCCS will continue to work with Contractors to achieve established AHCCCS goals and to meet
the immunization goals of Healthy People 2010. Contractors that do not show demonstrable and
sustained improvement may be required to submit to AHCCCS corrective action plans to improve
immunization rates.

AHCCCS Annual Immunization Assessment, Contract Year 2001

iv

A REPORT ON THE IMMUNIZATION STATUS OF AHCCCS MEMBERS
2 YEARS OF AGE
Contract Year 2001 (October 1, 2000, to September 30, 2001)
I.

INTRODUCTION

Background
Prevention of disease is the most cost-effective approach to health care. Once a disease process begins,
the economic impact on the health care system begins to mount. There are a number of ways to prevent
disease. One way is isolation from infectious disease or elimination of the disease. But as people
become increasingly mobile, it is almost impossible to isolate them from infectious disease. Despite
attempts to eradicate several vaccine preventable infectious diseases, many continue to exist. Thus,
vaccination is the most effective way of preventing disease.
Vaccination coverage levels of 90 percent are, in general, sufficient to prevent circulation of viruses
and bacteria that cause many diseases.1 Monitoring of immunization rates is critical to identifying
undervaccinated populations and increasing coverage levels.
The Arizona Health Care Cost Containment System (AHCCCS) ensures that vaccinations are provided
to children and adolescents as part of the Early and Periodic Screening, Diagnosis and Treatment
(EPSDT) package of services. Vaccines are distributed at no charge to providers who are enrolled in
the federal Vaccines for Children (VFC) program which are provided then to AHCCCS members
younger than 19 years.
AHCCCS requires that children and adolescents are vaccinated according to the most current
Recommended Childhood Immunization Schedule, which is approved by the Advisory Committee on
Immunization Practices (ACIP), the American Academy of Pediatrics (AAP) and the American
Academy of Family Physicians (AAFP). The schedule recommends vaccines that are intended to
immunize children against these diseases: diphtheria, tetanus, pertussis (also known as whopping
cough), poliomyelitis, hepatitis B, Haemophilus influenza type b, measles, mumps, rubella,
pneumococcal disease and varicella (also known as chicken pox). Vaccination for hepatitis A also is
recommended in selected high-risk areas, including Maricopa County, Arizona.
In recent years, several new vaccines and combinations of vaccines have been introduced. The newest
of these is pneumococcal conjugate vaccine (PCV), which is recommended as a routine immunization
for children up 2 years old and for certain high-risk children younger than 5 years old. Assessment of
PCV immunization was not included in this study because of its recent introduction, and because
manufacturing delays limited availability of the vaccine during the AHCCCS contract year being
reported (October 1, 2000 to September 30, 2001). Hepatitis A immunization also was not studied
because it is not recommended as a routine vaccination in all areas of the state.
Continued vigilance of immunization levels is important, as decreased immunization rates will likely
result in outbreaks of disease. The following table includes the number of reported cases of vaccinepreventable diseases that have occurred in the state of Arizona since 1998. The number of cases are
for the total population and are not age-specific.
AHCCCS Annual Immunization Assessment, Contract Year 2001

1

Reported cases of vaccine-preventable diseases in Arizona
1998
1999

2000

2001

Diphtheria
Polio
Hib < 5 years
Hepatitis A
Hepatitis B
Measles
Mumps
Meningococcal
Pertussis
Rubella
Tetanus
Congenital Rubella Syndrome

0
0
353**
467
215**
0
6
33
112
1
0
0

0*
0*
74
411
161
1
1
19
637
0
0*
0*

0
0
8
1841
185
11
6
48
245
2
1
0

0
0
3
700
138
1
1
44
75
13
0
2

Sources: Arizona Department of Health Services 4 and MMWR February 1, 2002 5
NOTES:* Data are from January 1, 2001, through June 19, 2001.
** Data from the Arizona Department of Health Services and MMWR were compared. Where differences were
noted, the higher number was used.
Data for varicella were not reported.

As seen above, pertussis has increased dramatically in 2001. The increase in pertussis cases originally
was thought to be associated with the use of acellular (or purified and inactivated) pertussis vaccine
instead of the whole-cell pertussis vaccine introduced in the 1940s. A recent study indicates that this
is not the case and that further investigation is needed to determine cause(s) for the rise in pertussis.6
Hepatitis A and B viruses also continue to be a problem in Arizona. Although there have been no
reported cases of some diseases, including diphtheria and polio, continued monitoring and
immunization is necessary to prevent a resurgence of these diseases.
All vaccines carry some risk of adverse effects, and it is expected that the risks associated with
vaccines will decrease with improvements in the manufacturing process. However, this risk is usually
minimal, compared with the serious health risks and possibility of death posed by different diseases.
In 1996, the most recent year for which complete mortality information is available, tetanus, pertussis,
measles, mumps and Haemophilus influenza type b accounted for 14 deaths nationally. Varicella
accounted for 81 deaths that year, 121 deaths were attributed to hepatitis A and 1,082 deaths were
attributed to hepatitis B.1 Appendix C explains the different diseases discussed in this study, along with
their complications.
AHCCCS and Healthy People 2000 and 2010 Goals
AHCCCS has established goals for Contractors to achieve in immunizing 2-year-old members.
Contract year 2001 goals for individual vaccinations include:
·
Diphtheria, Tetanus and acellular Pertussis (DTaP) (four doses) - 82 percent
·
Inactivated poliovirus vaccine (IPV) (three doses) - 88 percent
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·
·
·
·

Measles, mumps, rubella (MMR) (one dose) - 90 percent
Haemophilus influenza type b (Hib) (two doses) - 90 percent
Hepatitis B (HBV) (three doses) - 87 percent
Varizella (VZV) – (one dose) - 67 percent

The AHCCCS goals for series of immunizations include:
·
DTaP, IPV, MMR (4:3:1 series) - 82 percent
·
DTaP, IPV, MMR, Hib, and HBV (4:3:1:2:3 series) - 73 percent
In establishing immunization goals, AHCCCS used as a guideline the U.S. Department of Health and
Human Services (DHHS) immunizations goals, as published in Healthy People 2000: National Health
Promotion and Disease Prevention Objectives and Healthy People 2010. The 2000 objectives include
a 90-percent rate for individual immunizations and the 4:3:1 series that includes DTaP, IPV and MMR
vaccinations. The 4:3:1 series will be measured as part of Healthy People 2010; however, the focus
in future years will be completion of the five-antigen series of recommended vaccines.9 A goal of
Healthy People 2010 is that 80 percent of children 19-35 months old receive the 4:3:1:2:3 series.
In order to target progress toward these long-range goals, or benchmarks, AHCCCS has set interim
goals for Contractors to meet each year. For example, the AHCCCS five-antigen series goal for CY
2001 is 73 percent, which is the 1998 baseline measurement for this series published in the Healthy
People 2010 objectives.
Strategies that have Improved Immunization Rates
In the last decade, immunization coverage levels have increased nationwide.1 For example, in calendar
year 2000, 77.6 percent of American children 19 to 35 months old were fully immunized with the 4:3:1
series, according to the National Immunization Survey conducted by the Centers for Disease Control
and Prevention (CDC).6 This rate was 55 percent in 1991.1
Strategies that have helped increase the number of children vaccinated, both nationally and in Arizona,
include:
· implementation of Standards for Pediatric Immunization Practices, a set of recommendations for
all health care providers to ensure progress toward achieving Healthy People 2000 immunization
objectives. These standards were designed to help eliminate barriers and missed opportunities that
impede vaccine delivery.1
· education of families/caregivers and providers regarding appropriate record keeping, storage and
tracking of immunizations.
· implementation of the Arizona State Immunization Information System (ASIIS), a centralized
database of vaccinations reported by all types of providers. This database has information available
at no charge for providers when there is a question about whether a child’s immunizations are
current. This is particularly helpful for children who are transient and/or are seen by multiple
providers throughout the state, since providers may be reluctant to vaccinate patients who do not
have immunization records with them. Use of ASIIS to check patients’ immunization status should
prevent the need for patients to return for vaccinations.
· requirements by states, including Arizona, that children have certain immunizations prior to
starting school or attending a licensed day-care facility.
· patient reminders and recall, which have been found to be effective in improving vaccination rates.
AHCCCS Annual Immunization Assessment, Contract Year 2001

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·

·

Mail and telephone reminders to both patients’ homes and to providers are equally effective.1
provider and member education. Practice-based assessment of immunization rates and feedback
to staff involved has also been found to be effective. This is accomplished through outreach by the
Arizona Immunization Program Office (AIPO), The Arizona Partnership for Immunization (TAPI)
and AHCCCS Contractors.
the use of incentives. Several AHCCCS Contractors offer incentives; for example, a gift certificate
when a parent provides proof that a child is fully immunized by 2 years old.

II. PURPOSE OF THE STUDY
Arizona places a high priority on childhood immunizations to prevent disease and death. AHCCCS
and its Contractors have been very active with efforts to improve immunization rates. In 1993, the
Arizona Legislature enacted House Bill 2044, which requires that an assessment and a written report
describing the immunization status of two-year-olds enrolled in the AHCCCS program be submitted
annually to the Governor.
This study was the ninth annual assessment on the immunization status of AHCCCS members, two
years of age. It covered the AHCCCS contract year from October 1, 2000, to September 30, 2001 and
analyzed immunization completion rates among children enrolled in AHCCCS under Medicaid (Title
XIX of the Social Security Act) and KidsCare (Title XXI, the State Child Health Insurance Program,
or SCHIP). Results of this immunization assessment were compared with results of previous years’
results to provide a base against which improvement can be measured. The study also identified
potential areas for improvement.
III. IMMUNIZATION RECOMMENDATIONS AND QUALITY INDICATORS
During the time frame of this study, the Centers for Disease Control and Prevention (CDC)
recommended immunizing children for 12 preventable diseases. Specific recommended immunizations
discussed in this report are: diphtheria, tetanus, and acellular pertussis (DTaP) vaccine, inactivated
poliovirus (IPV) vaccine, measles, mumps and rubella (MMR) vaccine, Haemophilus influenza type
b (Hib) vaccine, hepatitis B virus (HBV) vaccine, and varicella zoster virus (VZV) vaccine. In
addition, single doses of combined antigens were separated into the appropriate primary vaccines for
reporting purposes. These combination vaccines include Tetra-immune (TETRA), which combines
DTaP and Hib in a single immunization, and COMVAX, which combines Hib and HBV. Derivatives
of the primary vaccines, such as oral poliovirus vaccine (OPV) and diphtheria, tetanus toxoids and
pertussis (DTP) also were included in the results.
This study used the Health Plan Employer Data and Information Set (HEDIS®) 2001 methodology,
which was developed by the National Committee for Quality Assurance (NCQA) and includes
immunizations recommended by the CDC is 2001. In order to measure improvement and establish
trends, results based on both the current and past years' HEDIS® criteria are presented. All quality
indicators are based on identical criteria for the denominator (i.e., children eligible for the study).

AHCCCS Annual Immunization Assessment, Contract Year 2001

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The denominator in the study sample consisted of children:
·
whose second birthdays occurred on or between October 1, 2000, and September 30, 2001, and
·
who had at least 12 months of continuous enrollment prior to, and including, their second birthdays
(one disenrollment period of 30 days or less in the 12-month period was allowed).
Definitions of the current quality indicators follow:
Primary Quality Indicators
1. DTaP Immunization Rate
Numerator: The number of children in the denominator who received at least four DTaP doses by their
second birthdays
2. IPV Immunization Rate
Numerator: The number of children in the denominator who received at least three IPV doses by the
their second birthdays (OPV used only in selected cases)
3. MMR Immunization Rate
Numerator: The number of children in the denominator who received at least one MMR dose between
their first and second birthdays
4. Hib Immunization Rate
Numerator: The number of children in the denominator who received at least two Haemophilus
influenza type b doses by their second birthdays, with at least one of them falling on or between the
first and second birthdays
5. HBV Immunization Rate
Numerator: The number of children in the denominator who received at least three HBV doses by the
their second birthdays, with at least one of them falling on or between the sixth-month of life and
second birthdays
6. VZV Immunization Rate
Numerator: The number of children in the denominator who received at least one varicella vaccine
with a date of service falling on or between their first and second birthdays
7. HEDIS® 2001 Combination #1 (4:3:1:2:3)
Numerator: The number of children in the denominator who received the appropriate doses of DTaP,
IPV, MMR, Hib and HBV by their second birthdays
8. HEDIS® 2001 Combination #2 (4:3:1:2:3:1)
Numerator: The number of children in the denominator who received the appropriate doses of DTaP,
IPV, MMR, Hib, HBV and VZV by their second birthdays
In addition to the primary quality indicators listed above, two HEDIS® indicators from prior years were
reported. This provides Contractors with more information for assessing their immunization rates.

AHCCCS Annual Immunization Assessment, Contract Year 2001

5

Additional Quality Indicators
1. Three-Antigen Combined Immunization Rate (4:3:1)
Numerator: The number of children in the denominator who received the appropriate doses of DTaP,
IPV and MMR by their second birthdays
2. HEDIS® 3.0/1999 Five-Antigen Combined Rate (4:3:1:2:2)
Numerator: The number of children in the denominator who received the appropriate doses of DTaP,
IPV, MMR, Hib and 2 doses of HBV by their second birthdays
Any antigens administered after 24 months of age were not included in the numerator. HEDIS®
restricts the timing of doses of MMR, Hib, HBV and VZV, according to CDC recommendations.
Children who received their last dose of MMR, HIB or VZV vaccine before 12 months of age were
not included in the numerator. At least one dose of HBV must have been administered after six months
of age for the immunization to be included in the numerator.
IV. METHODOLOGY
The primary immunizations included in this assessment were DTaP, IPV, MMR, Hib, HBV and VZV.
The primary vaccines that comprise the combined antigens (i.e., Tetra-immune, which includes DTaP
and Hib in a single immunization, and COMVAX, which consists of Hib and HBV together) were
reported separately in the appropriate categories. Derivatives of primary vaccines, such as oral polio
vaccine (OPV), and diphtheria, tetanus and whole-cell pertussis vaccine (DTP), also were included
in the results. Thus, all of the immunizations that a child might have received, relative to the primary
vaccines, were accounted for in the study.
Assessment Tool
AHCCCS contracted with Health Services Advisory Group Inc. (HSAG), an external quality review
organization, to assist with the annual immunization assessment. The state's ASIIS database also was
used to extract immunization data.
The assessment tool used for the AHCCCS immunization assessment in previous years was updated
for this study (see Appendix D). The assessment tool was designed in a scannable format that could
be recognized by Teleform (V5.4) software. This software package uses the latest technology in object
character recognition (OCR), which both improves data validity and reduces data processing time.
Scanning eliminates data entry, and the errors and clean up associated with keypunching.
Study Sample
AHCCCS identified the study group by defining a representative, stratified random sample of children
enrolled with each AHCCCS Contractor using a finite sampling factor and accounting for distribution
of members by county. Sample selection was calculated for each Contractor to provide a 99 percent
confidence level. The sample consisted of children whose second birthdays occurred between October
1, 2000, and September 30, 2001, and who had at least 12 months of continuous enrollment prior to,
and including, their second birthdays. One disenrollment period of 30 days or less in the 12-month
period was allowed.

AHCCCS Annual Immunization Assessment, Contract Year 2001

6

Data Collection
The data collection process for this study generally followed the same methodology as in the previous
two years, except that ASIIS, the statewide immunization registry operated by the Arizona Department
of Health Services (ADHS), also was used to collect immunization data. AHCCCS provided ASIIS
with two database files containing the sample cases of Medicaid and KidsCare children. AHCCCS
requested ASIIS to query and cross-match the members that AHCCCS provided against data in the
registry. AHCCCS also requested immunization data for those members where matches existed in the
ASIIS registry.
ADHS reformatted data received from AHCCCS to import the files into the batch query function of
PC-Immunize. PC-Immunize is an immunization software product used by ASIIS staff and providers
statewide. Using this batch query function, ASIIS staff searched the statewide immunization registry
by first name, last name, and date of birth.
Medicaid Members
Out of the AHCCCS sample size of 5,480 children enrolled under Medicaid, a total of 4,895 had a
single match in the registry and immunization data for these children was provided to HSAG and to
AHCCCS. A “single match” occurred when one matching record was found in the registry. In addition,
265 children had multiple matches in the registry. “Multiple matches” were those instances when more
than one record for each child existed in the ASIIS registry. The remaining 320 children had no
matching record in the registry. HSAG was given two files: the demographic information of the entire
sample of 5,480 children and the vaccine data of 4,895 children with a single match.
KidsCare Members
AHCCCS provided 978 names to ASIIS. Of these, 873 had a single match in the registry and
immunization data for these children was provided to HSAG and to AHCCCS. Thirty-six children had
multiple matches in ASIIS and the remaining 69 children had no matching records in ASIIS.
Excluded Cases
From the Medicaid sample of 5,480 cases, 117 members were excluded, for a final sample of 5,363.
Eighty three of the 117 members were excluded because they were enrolled with Arizona Health
Concepts, which no longer has an acute-care contract with AHCCCS. Another four cases were
excluded from the study when it became clear the children were older than 24 months prior to the start
of the study period. An additional 30 cases were excluded after their records indicated a parental
refusal or contraindication to immunization. Final sample sizes by individual Contractor ranged from
43 to 1,728 children.
From the KidsCare sample of 978 cases, 12 members were excluded, for a final sample of 966. Three
of the 12 members were excluded because they were enrolled with Arizona Health Concepts. Seven
cases were excluded after their records indicated a parental refusal or contraindication to
immunization. One case was determined to be invalid and was excluded from the study when it
became clear the child was older than 24 months prior to the start of the study period. Additionally,
one case was excluded after it was determined that child had two separate member identification
numbers. Final sample sizes by individual Contractor ranged from two to 335 children.

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7

HSAG merged and analyzed files received from ASIIS to determine whether those immunization
records were complete or incomplete, according to HEDIS® specifications. Overall, 24 percent of
records in ASIIS were found to be complete; that is, the registry showed that those children had all the
vaccinations expected by two years of age. A list of children who had incomplete immunization
records were sent to each Contractor with an appropriate number of assessment tools. Contractors were
responsible for obtaining and abstracting immunization records for the remaining children onto
scannable tools. As an alternative method to a full medical record assessment, AHCCCS allowed
Contractors to use two sources of data: medical records and administrative (claims) information. In
accordance with NCQA hybrid methodology, administrative data were combined with medical record
data only if there were at least two weeks between the administrative dates of service and the medical
record dates. This methodology allowed data from different sources to be combined, while reducing
the possibility of counting immunizations twice. Four of the 11 Contractors submitted data using this
hybrid methodology.
After immunization records were abstracted by the Contractors, the scannable tools were sent to
HSAG for entry into the database. HSAG validated all logical field-to-field comparisons that existed
in the data set (e.g., checked for immunizations prior to birth). This “clean” data was then merged with
the ASIIS data and the original sample file. Following HEDIS® specifications, immunizations found
in the medical record that were within 14 days of the ASIIS data (for the same immunization) were
considered to be the same immunization and were not counted twice.
Data Validation
In order to ensure the accuracy of data collected, a sample of 320 cases (five percent of the total
sample), stratified by Contractor, was chosen from those cases that had recorded immunization
information. The Medicaid sample consisted of 269 cases, while the KidsCare program had 51 cases.
Contractors' validation samples ranged from three to 103 cases. Following selection of the validation
sample, trained nurse abstractors from HSAG went to provider offices and abstracted the immunization
information onto the immunization tool. This tool was then scanned into a database and compared with
the original immunization information sent in by Contractors.
The validation of immunizations was conducted on several levels and is presented in a table on the
following page. First, the total number of immunizations given was compared across antigens
(Columns 2, 3 and 4). For example, Contractors showed 262 doses of MMR provided for the sample
cases, while HSAG only found 249, or a difference of 13 shots. The second level of analysis was based
on critical errors (Columns 5 and 6). Critical errors occur when the counts are different and the result
could have made a difference to the overall rate. Using IPV as an example, if a Contractor reported
one dose and HSAG found two doses, the results would not have affected the IPV rate, which requires
three doses by 24 months of age. However, if the Contractor had reported three doses and HSAG
found only two doses, this would be a critical error. VZV had 13 over-reported critical errors and eight
that were under-reported. This means that Contractors reported children who received the VZV
immunization 13 times that could not be verified, yet missed reporting eight children who received
the VZV immunization. The largest critical differences were under-reporting of HBV (12 times) and
over-reporting Hib (29 times).

AHCCCS Annual Immunization Assessment, Contract Year 2001

8

DATA VALIDATION SUMMARY
(Contract Year 2001)

DTaP
IPV
MMR
HIB (2 Doses)
HBV (3 Doses)
VZV
Total

Original
Abstraction
234
264
262
243
231
222
1,456

HSAG
Results
214
249
249
219
223
217
1,371

Difference
20
15
13
24
8
5
85

Critical Errors
Over
Under
23
3
17
2
19
6
29
5
20
12
13
8
121
36

% Kappa
Agreement
91.9%
94.1%
92.2%
89.4%
90.0%
93.4%
91.8%

The percent Kappa Agreement (last column) is calculated using the Kappa statistic. When computing
the agreement rate of DTaP, for example, the Kappa statistic takes into account the agreement in both
hits and misses (e.g., if the Contractor did not find a shot for DTaP and HSAG did not find a shot for
DTaP, then both are in agreement). Data validation included both medical records and data from
administrative databases. Antigen-specific results from this validation sample indicated better than a
90 percent agreement with the data that was previously submitted from the Contractors for five of the
six antigens. All of the antigens have some over- and under-reporting. Only one antigen fell below the
90 percent agreement level (Hib, at 89.4 percent). Although there did appear to be minimal overreporting, none appeared to come from any one particular Contractor. The few errors that were
observed appeared to occur strictly by chance. Contractors were just as likely to under-report as they
were to over-report. Consequently, comparative results of the antigen rates were not significantly
different between the original cases and the re-abstracted validation cases.
Data Analysis
Once data collection and validation was finalized, HSAG managed the database and conducted the
analysis using Stata (V5.0) statistical software. Stata statistical code was first developed to generate
antigen-specific and combined immunization rates for the initial Arizona immunization status report.
The computer code has been updated annually to address changes in recommended immunization
schedules and newly recommended antigens. In determining if a child is age-appropriately immunized
for a particular antigen, HSAG computer algorithms followed HEDIS® 2001 definitions.
The primary analysis provided results on the percentage of 2-year-old members that were ageappropriately immunized for each of HEDIS® 2001 quality indicators (DTaP, IPV, MMR, Hib, HBV,
VZV and the combined series rates). The HBV immunization rate also was calculated for two doses,
following the HEDIS®3.0 1999 criteria. This provides Contractors with additional information for
comparison to prior reports and other comparative study results. Additional analysis was conducted
to identify missed opportunities for DTaP vaccination and the degree of partially immunized children,
both by Contractor and by county.

AHCCCS Annual Immunization Assessment, Contract Year 2001

9

V. RESULTS
Combined Results (Medicaid and KidsCare Populations)
For all but one individual vaccination, rates of completed immunizations for the combined sample of
Medicaid and KidsCare members improved from the previous contract year. The only vaccination that
did not increase in the most recent year, DTaP, was only 0.2 percent below last year's level. This
decrease in DTaP immunization rates is consistent with national findings. The National Immunization
survey conducted by the CDC found that the four-dose rate for DTaP declined from 83.3 percent in
1999 to 81.7 percent in 2000 (these rates include commercially insured children, as well as those
covered under Medicaid and SCHIP programs).10
Rates of completion for two series of vaccinations among the combined sample also improved. The
4:3:1:2:3 series showed the greatest improvement, increasing 2.7 percentage points, from 63.4 percent
to 66.1 percent. This represents a relative improvement of 4.3 percent. The 4:3:1 series increased by
1.1 percentage points, from 78.0 percent to 79.1 percent. This represents a relative improvement of
1.4 percent. It should be noted that the combined rates are not an average of the individual antigens,
but a measurement of the number of children who had all of the required immunizations.
AHCCCS has established long-range goals for immunization completion rates for individual antigens
and antigen series. These goals are based on Healthy People 2000: National Health Promotion and
Disease Prevention Objectives published by the U.S. Department of Health and Human Services, as
well as revised objectives contained in Healthy People 2010. AHCCCS also has set interim goals
based on the statewide average of all Contractors' performance for previous years. AHCCCS goals for
immunization completion rates in four categories (including the DTaP immunization, which was
within 0.2 percent of the AHCCCS goal) were met by the combined population during contract year
(CY) 2001 (October 1, 2000, through September 30, 20001). The following is a comparison of rates
of individual immunizations and antigen-series rates for all children included in the study in CYs 2000
and 2001 with AHCCCS goals. These results also are compared with Healthy People goals.
COMBINED TWO-YEAR-OLD IMMUNIZATION RATES
(Medicaid and KidsCare Populations)
Immunizations
(doses)
All children,
CYE 2000
All children,
CYE 2001
AHCCCS
Goals*
Healthy People
2010 Goals
Notes:

DtaP
(4)

IPV
(3)

MMR
(1)

Hib
(2)

HBV
(3)

VZV
(1)

4:3:1
Series

82.0%

87.9%

87.3%

82.8%

77.7%

71.9%

78.0%

63.4%

81.8%

88.5%

90.0%

83.4%

80.4%

78.5%

79.1%

66.1%

82.0%

88.0%

90.0%

90.0%

87.0%

67.0%

82.0%

73.0%

90.0%

90.0%

90.0%

90.0%

90.0%

N/A**

90.0%

80.0%

4:3:1:2:3
Series

* AHCCCS goals are for CY 2001
** No Healthy People goals established for this antigen

AHCCCS Annual Immunization Assessment, Contract Year 2001

10

AHCCCS Contractors have maintained immunization rates despite a significant increase in AHCCCS
membership. Combined enrollment in the AHCCCS acute Medicaid and KidsCare programs increased
by 21 percent during CY 2001. Accordingly, the total sample size for this study increased by 18.3
percent from the previous year.
It should be noted that, unlike previous years, virtually all records in the sample selected by AHCCCS
were found, either through ASIIS or by locating the medical chart. In past years, the percent of missing
records in this study has decreased dramatically, from more than 12 percent in 1993 to 1.2 percent in
2000. The use of ASIIS as an additional data source has further improved the ability to collect
immunization records for this study. Of the final combined sample of 6,329 Medicaid and KidsCare
members, medical charts for two members could not be located. AHCCCS was unable to confirm
whether records for these two children were contained in ASIIS because there were not exact matches
of demographic information (name, birth date, etc.).
Medicaid Program Results
All of the individual immunization rates were at or above 80 percent, except VZV (77 percent). The
4:3:1 and 4:3:1:2:3 series rates maintained their trend of small, but continuous increases. The 4:3:1
series completion rate for Medicaid-eligible children reached its highest level in CY 2001, at 78.1
percent. While this series only includes a few of the vaccinations required, it continues to be measured
as an indicator of long-term trends. The 4:3:1:2:3 series completion rate for Medicaid-eligible children
also was at its highest, 65.1 percent, in this reporting period. AHCCCS also measured the 4:3:1:2:3:1
series, which includes varicella vaccine; that rate improved from 53.4 percent in the previous
measurement year to 56.5 percent.
Results for Medicaid-eligible children from 1998 through 2001 are summarized in the following table.
Rates for all individual vaccines and immunization series have increased during that time. The smallest
increase was for hepatitis B vaccine, which increased 1.1 percentage point from 1998 to 2001. The
largest increase was for varicella, which improved by 33.4 percentage points, or a relative
improvement of 76 percent. (Varicella zoster vaccine, or VZV, was licensed for use in healthy children
and adults in March 1995 and first included in the AHCCCS annual immunization assessment for the
1997 contract year.)
IMMUNIZATION RATES
(Medicaid-eligible Children)
CONTRACT
YEAR
1998
1999

DTaP
(4)
75.0%
79.9%

IPV/OPV
(3)
84.8%
87.2%

MMR
(1)
83.0%
86.8%

Hib
(2)
80.8%
82.2%

HBV
(3)
79.7%
79.5%

VZV
(1)
43.7%
62.8%

4:3:1
Series
70.0%
75.4%

4:3:1:2:3
Series
60.7%
61.9%

2000
2001
AHCCCS
Goals

81.4%
81.0%

88.3%
87.7%

87.6%
89.7%

84.3%
83.8%

80.0%
80.8%

71.1%
77.1%

77.5%
78.1%

64.7%
65.1%

82%

88%

90%

90%

87%

67%

82%

73%

Notes:

Numbers in parentheses below the antigen represents the number of doses.
IPV is the preferred vaccine over OPV. DTaP is the preferred vaccine over DTP.
* AHCCCS goals are for CY 2001

AHCCCS Annual Immunization Assessment, Contract Year 2001

11

AHCCCS has made significant progress toward meeting goals for immunization completion rates
among Medicaid-eligible children. Rates for IPV and MMR are within 0.3 of a percent of the
AHCCCS goals, and DTaP is only one percentage point below the goal for that antigen. The rate for
VZV exceeded the AHCCCS goal by 10.1 percent.
The following graph displays the annual trend in the combined DTaP, IPV and MMR rate from 1994
to present.

ANNUAL TREND IN DTAP, IPV AND MMR COMBINED SERIES
(Percentage Rates from Contract Years 1994 through 2001)
100
80

80
60

72

70
58.5

63

58.6

64.7

82

80
70

75.4

77.5

82

78.1

40
20
0
1994

1995

1996

AHCCCS Medicaid Rate

1997

1998

1999

2000

2001

AHCCCS CY Goal

Note: AHCCCS goals were not established for CYs 1994 and 1995

The other antigen series for which AHCCCS has a goal is the 4:3:1:2:3 series. The AHCCCS rate for
this series has increased by 4.4 percentage points, from 60.7 percent in 1998 (when this combination
was first measured) to 65.1 percent in 2001.
KidsCare Program Results
This is the second year of reporting immunization rates for children enrolled in AHCCCS under
KidsCare, Arizona Child Health Insurance Program (Title XXI of the Social Security Act). The
KidsCare program was implemented November 1, 1998, and is designed to decrease the number of
children in Arizona who are without health care coverage. This study includes nine Contractors that
provide KidsCare coverage, but results are presented in aggregate because individual sample sizes are
too small to yield meaningful results.
Immunization rates for KidsCare children were nearly identical to the Medicaid immunization
rates, as seen in the table below. Rates for KidsCare members were slightly higher than rates for
Medicaid children in six of the eight antigen categories.

AHCCCS Annual Immunization Assessment, Contract Year 2001

12

COMPARISON OF KIDSCARE AND MEDICAID TWO-YEAR-OLD IMMUNIZATION RATES
Immunizations
(doses)
KidsCare
Medicaid

DTaP
(4)

IPV
(3)

MMR
(1)

HIB
(2)

HBV
(3)

VZV
(1)

4:3:1
Series

4:3:1:2:3
Series

82.5%
81.0%

89.3%
87.7%

90.2%
89.7%

83.0%
83.8%

79.9%
80.8%

79.9%
77.1%

80.1%
78.1%

67.0%
65.1%

AHCCCS goals were achieved for four antigens: DTaP, IPV, MMR and VZV. KidsCare rates for
two immunization series (4:3:1 and 4:3:1:2:3), were 2 percentage points higher than rates for the
Medicaid sample. As seen in the following summary of KidsCare immunization rates,
improvement was made in all but one antigen, the DTaP vaccine.
IMMUNIZATION SUMMARY
(KidsCare-eligible Children)
CONTRACT
YEAR
2000
2001

DTaP
(4)
82.6%
82.5%

IPV
(3)
87.4%
89.3%

MMR
(1)
87.0%
90.2%

Hib
(2)
81.2%
83.0%

HBV
(3)
75.4%
79.9%

VZV
(1)
72.7%
79.9%

4:3:1
Series
78.5%
80.1%

4:3:1:2:3
Series
62.1%
67.0%

AHCCCS Goals

82%

88%

90%

90%

87%

67%

82%

73%

VI. ANALYSIS
AHCCCS overall rates compare favorably with the Medicaid national average, as well as with
commercial health plans' rates. The NCQA national Medicaid and commercial averages for childhood
immunizations are presented in the table below for comparative purposes. The 2001 AHCCCS
immunization rate for the 4:3:1:2:3 series (DTaP, IPV, MMR, Hib and HBV) compares favorably to
the 2000 NCQA national average for Medicaid plans and, as expected, is below the average for
commercial health plans. However, the AHCCCS 2001 rate for the 4:3:1:2:3:1 series, which includes
varicella vaccine, is above 2000 NCQA national averages for both Medicaid and commercial health
plans.
COMPARISON OF AHCCCS MEDICAID RATES WITH NATIONAL AVERAGES

4:3:1:2:3 Series
4:3:1:2:3:1 Series

AHCCCS
Medicaid
65.1
56.5

2000 NCQA National Averages
Medicaid
Commercial
66.8
69.8
53.5
55.7

Source: National Committee for Quality Assurance

AHCCCS Annual Immunization Assessment, Contract Year 2001

13

Several AHCCCS Contractors included in this study exceeded AHCCCS CY 2001 goals for individual
antigens or for immunization series, and some achieved or surpassed Healthy People 2000 objectives.
Ten of 11 Contractors exceeded the AHCCCS goal for varicella vaccine, seven Contractors exceeded
the AHCCCS goals for both DTaP and MMR, and six Contractors surpassed the AHCCCS goal for
IPV. Four Contractors met or exceeded the AHCCCS goal of 82 percent for the 4:3:1 series and two
surpassed the AHCCCS goal of 73 percent for the 4:3:1:2:3 series.
The antigen-series rates were impacted most by the DTaP antigen, which had the lowest rate among
those antigens included in the combined rate. DTaP is the only antigen that requires four doses by two
years of age. Sixty percent of children in the Medicaid group who were not fully immunized for DTaP
had received three of the four recommended doses. Although the DTaP rate reached a high of 81
percent in 2001, The DTaP rate could have been 92.5 percent had those children who had three doses
of DTaP received one more dose.
In previous years, these combination rates also were impacted by HBV. In 1998, only two doses of
HBV were required to be age-appropriately immunized. This was to allow for Contractors that could
not adequately capture the first dose of HBV which was typically administered in the hospital. This
requirement was changed back to three doses in 1999 to monitor HEDIS® 2001 specifications. The
third dose of HBV affected the five-antigen combination series. The rate for the series that included
three doses of HBV was 2 percentage points lower than the rate with only two doses of the vaccine.
This gap, however was narrower in 2001 than in previous years.
Limited supplies of vaccine and delays in shipping may have resulted in some missed opportunities
for vaccination during the study period. In mid-2000, Wyeth Lederle Inc. and Baxter Healthcare Corp.
stopped producing diphtheria, tetanus and acellular pertussis (DTaP) vaccine. Providers who
participate in the VFC Program have been asked to keep no more than a one-month supply of some
vaccines. This situation may have posed a barrier to improvement in the DTaP rate for CY 2001.
The only single antigen rate that was less than 80 percent was varicella, or VZV, with a rate of 77
percent. This rate has improved from 43.78 percent in 1998 to 77.1 percent in 2001. This increase
indicates a high demand for VZV, as parents hope to spare their children (and themselves) the effects
of this highly contagious disease. Only one Contractor had a VZV rate for 2001 below 70 percent, at
41.9 percent.
VII. CONCLUSIONS AND RECOMMENDATIONS
The annual AHCCCS immunization assessment documents the rate of two year old Medicaid- and
KidsCare-eligible children who obtained complete antigen-specific and antigen-series immunizations.
As the 2001 study demonstrated, rates of completed immunizations for all but one antigen improved
from the previous contract year. In general, immunization rates for KidsCare members proved to be
nearly identical to rates for those children covered under Medicaid.

AHCCCS Annual Immunization Assessment, Contract Year 2001

14

Certain vaccinations pose greater challenges for completion of all doses. In the past, DTaP has been
the primary antigen limiting AHCCCS overall immunization rates for combined antigens. This is not
surprising since DTaP is the only antigen that requires four doses by 2 years of age. A combinedantigen rate can equal, but never exceed, the lowest individual-antigen included in the combined rate.
Efforts to improve the DTaP rate have been somewhat successful, as reflected in an increase in the
overall Medicaid rate for this antigen over the last few years.
In addition to DTaP, Contractors must now focus on ensuring that members receive two doses of Hib
and three doses of HBV. Despite steady increases in the rates for these antigens, overall rates for Hib
and HBV both are more than 6 percentage points below the AHCCCS goals for those antigens. To
continue the upward movement and achieve Healthy People 2010 immunization goals, a concerted
effort to increase rates for Hib and HBV (which can be given together in a single COMVAX shot), as
well as maintain rates for other antigens, is needed.
In late 2001, the CDC recommended deferral of the fourth dose of DTaP (usually given at 15 to 18
months) to help ensure that younger children are able to receive the first three doses. The Arizona
Department of Health Services did not implement this recommendation until early 2002. The shortage
of DTaP is expected to continue well into 2002, and also may affect results of next year's AHCCCS
immunization assessment.7
This year's total study sample, including Medicaid and KidsCare members, represented an increase of
18.3 percent over last year's sample. This growth is due to a similar increase in the AHCCCS total
population. Overall, Contractors maintained or improved immunization rates from last year's
assessment despite a significant increase in enrollment.
Much of the improvement in immunization rates over the past several years is due to the partnership
among AHCCCS, Contractors and providers. To achieve this AHCCCS, Contractors and providers
created and implemented the use of tracking forms for Early and Periodic Screening, Diagnosis and
Treatment (EPSDT) services. EPSDT benefits include all age appropriate immunizations and these
tracking forms provide a convenient way for primary care practitioners to document all immunizations
given, along with other well-child services, during an office visit. Contractors require provides to use
these forms and to submit copies to them for monitoring and follow-up. In addition, Contractor
outreach efforts have also been successful in encouraging families to complete immunizations for their
children. Other Contractor activities that facilitate access to services, such as providing transportation
and assistance with scheduling appointments, have contributed to the steady increase in AHCCCS
immunization rates.
Collaboration with the Arizona Department of Health Services (ADHS) Immunization Program Office,
which administers the state's Vaccines for Children (VFC) program and the ASIIS registry, has
contributed to improvement in immunization rates. Further efforts through The Arizona Partnership
for Immunization (TAPI), of which AHCCCS is a key member, have raised public awareness of the
importance of immunizations and provided a forum for many organizations to collaborate toward a
common goal.

AHCCCS Annual Immunization Assessment, Contract Year 2001

15

As anticipated, the ASIIS automated registry relieved some of the Contractors' burden for locating
immunization information. ASIIS was created in 1996 as a statewide immunization registry and
currently supports PC-Immunize and PCI2000 software. As of January 1998, Arizona state law
requires providers to report immunizations to ASIIS. In this study, 24 percent of completed records
were found in the ASIIS database. This is an increase from the 18 percent of complete records found
in ASIIS last year, when AHCCCS validated use of this system to collect data for its annual
assessment. More efforts need to be done to improve communication by all providers. As more ASIIS
records are found to be complete, Contractors will spend less time collecting immunization records
each year and can devote staff resources to ensuring that more children are fully immunized.
In addition, the following strategies should help support continued progress toward achieving
AHCCCS goals and Healthy People 2010 objectives:
·

Ensure that the CDC's Standards for Immunization Practices are implemented to the greatest
extent possible at the Contractor and provider levels. These standards, which are included in
Appendix E, were developed in 1992 by the National Vaccine Advisory Committee and have been
endorsed by more than a dozen professional health care and advocacy organizations.

·

Utilize patient reminder and recall strategies. These may be automated, such as computer-generated
lists or phone calls to patients with a recorded message, or may include more "low-tech"
approaches, such as mailed reminders to patients or an "Immunization Due" stamp or clip to flag
charts for providers.

·

Vaccinate at every opportunity and administer multiple vaccinations when indicated. Providers
may miss opportunities to vaccinate because of concerns about administering several vaccines
simultaneously. These concerns include reduced immune response and increased potential for
adverse events, but neither is supported by scientific data.1 Health care providers need to educate
parents/caregivers about the safety and efficacy of administering multiple vaccines. The licensing
of additional combination vaccines is expected in the near future and may help to alleviate parental
objections about administering several shots at once.

·

Continue utilizing the ASIIS registry, claims data and EPSDT tracking forms to determine the
immunization status of members. Contractors can use these resources to specifically target
individuals due for vaccinations. This could potentially impact overall immunization rates,
especially those antigens that require only one dose (MMR and VZV), or to ensure that children
who have three doses of DTaP receive the fourth dose before their second birthdays.

·

Consider developing targeted outreach activities to certain groups or geographic areas. NIS data
indicate that Native Americans, African Americans and Hispanics are likely to have lower
immunization coverage levels.10 Monitoring coverage in specific geographic areas, such as at the
county level, may help Contractors target interventions to increase immunization and prevent
outbreaks of disease.

AHCCCS Annual Immunization Assessment, Contract Year 2001

16

Immunization awareness in Arizona has increased and many organizations have made a concerted
effort to improve the immunization status of children by 2 years of age. However, as AHCCCS
immunization rates come closer to meeting Healthy People goals, it will become more difficult to
target improvement and reach those members who are most at-risk for not receiving complete
immunizations.
AHCCCS will continue to work with Contractors to achieve established AHCCCS goals and to meet
the immunization goals of Healthy People 2010. Contractors that do not show demonstrable and
sustained improvement may be required to submit to AHCCCS corrective action plans to improve
immunization rates.
VIII. REFERENCES
1.
2.

3.
4.
5.
6.
7.
8.
9.
10.
11.

Centers for Disease Control and Prevention. Epidemiology and Prevention of VaccinePreventable Diseases 6th Edition, January 2000, second printing, January 2001.
U.S. Department of Health & Human Services, Centers for Disease Control and Prevention,
National Immunization Program, Vaccine Information Statements for MMR (12/16/98),
Hepatitis B (12/16/98), Hib (12/16/98), DTP/DTaP/DT (8/15/97), Varicella (12/16/98), Polio
(2/6/97), Polio (1/1/2000).
National Immunization Program – Chart - Recommended Childhood Immunization Schedule
United States, January – December 2001.
Arizona Department of Health Services – Immunizations – A Publication of the Arizona
Immunization Program Office, Spring 2001.
Centers for Disease Control and Prevention. Morbidity and Mortality Weekly Report (MMWR)
February 1, 2002, 51(4); 81-91.
Centers for Disease Control and Prevention. Morbidity and Mortality Weekly Report (MMWR)
August 3, 2001, 50(30); 637-641.
Centers for Disease Control and Prevention. Pertussis – United States, 1997-2000. MMWR
February 1, 2002, 51(4); 73-80.
Centers for Disease Control and Prevention. Update on the supply of tetanus and diphtheria
toxoids and of tetanus and diphtheria toxoids and acellular Pertussis vaccine. MMWR
2001:50: 189-90.
Healthy People 2000: National Health Promotion and Disease Prevention Objectives, website
http://www.cdc.gov/nchs/data/hp2000/hp2k01-acc.pdf
Healthy People 2010: Vol. 1: Objective for Improving Health (Part A: Focus Areas 1-14), U.S.
Department of Health and Human Services, November 2000.
www.ncqa.org/somc2001/APPX_TABLES/SOMC_2001_APPX_PUBLIC.html.

AHCCCS Annual Immunization Assessment, Contract Year 2001

17

APPENDIX A
LIST OF IMMUNIZATIONS AND COMBINED ANTIGENS
________________________________________________________________________________
DTaP

Diphtheria, tetanus toxoids and acellular pertussis (other
derivatives are DTP, Td and TD)

IPV

Inactivated poliovirus vaccine (oral poliovirus vaccine, or OPV,
used in selective cases)

MMR

Measles, mumps and rubella

Hib

Haemophilus influenza type b

HBV

Hepatitis B vaccine

VZV

Varicella zoster vaccine

TETRA

DTaP and Hib in a single immunization

COMVAX

Hib and HBV in a single immunization

APPENDIX B
DISEASE
Hepatitis B (HBV)

Diphtheria

Tetanus

Pertussis

Haemophilus
influenza type b
(Hib)

CLINICAL
MANIFESTATIONS
Occur more frequently in adults than in
children however symptoms may include
jaundice, anorexia, nausea, vomiting,
right upper quadrant abdominal pain,
fever, headache, myalgias, skin rashes,
arthralgias, arthritis and dark urine
Cold like symptoms, such as sore throat,
anorexia,
and
low-grade
fever.
Respiratory obstruction may occur.
Eventually the tonsils and soft palate will
be covered with a bluish-white
membrane. Widespread use of vaccines
began in the late 1940s
Lockjaw, stiffness of the neck, difficulty
swallowing, rigid abdominal muscles,
fever, hypertension, and tachycardia.
Complete recovery can take months.
Neonatal tetanus is rare in the United
States however there are over 270,000
estimated annual cases worldwide.
Vaccines were started in the 1940s. Since
the 1970s there have been between 50100 cases reported annually. Prior to the
1970s there were 500-600 cases reported
per year
Cold-like symptoms (first stage),
coughing spells that end in a high-pitched
whoop. Cyanosis can occur at the second
stage, with gradual recovery in 2-3 weeks
(convalescent stage). The most common
complication is secondary bacterial
pneumonia, which is the cause for most
of the deaths. Overall case-fatality rate
0.2% (84% are children under the age of
six months). Prior to the 1940s there
were 200,000 cases annually in the
United States. Since 1980 there are
approximately 3700 cases annually
Meningitis, epiglottitis, pneumonia,
arthritis, cellulitis, osteomyelitis and
bacteremia. Others experience hearing
impairment or neurologic sequelae.
Over-all case fatality rate is 2-5%. This
disease is rare after five years of age

AHCCCS Annual Immunization Assessment, Contract Year 2001

RESEVOIR

TRANSMISSION

Human carrier

Parenteral or mucosal
exposures from others
who have HBV or
carriers

Human carrier

Respiratory tract, and
rarely from skin lesions
or from contaminated
articles

Organisms from the
soil and intestinal
tracts of animals and
humans

Contaminated wounds.
Tetanus can also occur
with an ear infection,
dental infection, animal
bite,
abortion
or
pregnancy

Human carrier

Respiratory droplet, at
times
by
airborne
droplets of respiratory
secretions or freshly
contaminated articles

Human carrier

Most
likely
respiratory droplet

by

2

Measles

Maculopapular rash, fever, cough,
Koplik’s spots (blue-white spots on the
buccal mucosa), cold-like symptoms,
anorexia,
diarrhea,
generalized
lymphadenopathy and conjunctivitis

Human carrier

Mumps

Parotitis, myalgia, anorexia, malaise,
headache and low-grade fever

Human carrier

Rubella

Low-grade fever, malaise, swollen glands
and upper respiratory infection (URI)
prior to a rash. In 1964 there was a
rubella epidemic with 12.5 million
people contracting rubella and 20,000
with congenital rubella syndrome (CRS).
One infant with CRS has an estimated
$200,000 cost for medical care over their
lifetime. The cost of the 1964 epidemic
was $840 million; this does not include
the emotional aspects incurred from this
epidemic
Fever, and malaise prior to a rash in
adults. Children usually present with a
rash initially. Pruritus is common. Herpes
Zoster (shingles) occur when the VZV
reactivates
Nonparalytic aseptic meningitis, flaccid
paralysis and death. There are cases of
subclinical polio. These cases are
considered contagious and can transmit
the disease to others. From 1980-1999
there have been an average of eight cases
annually. 95% were vaccine associated
paralytic polio caused by the live oral
polio vaccine, thus most people are now
given Inactivated Polio Vaccine (IPV)

Human
carrier
Infants
with
congenital rubella
may shed the virus
for up to one year

Varicella (VZV also known as
Chicken Pox)
Poliomyelitis (polio)

Human carrier

Human carrier

Large
respiratory
droplets and aerosolized
droplet nuclei, which can
be present in a room for
up to two hours, after a
person with measles has
occupied the area
Airborne or through
direct contact with
infected droplet nuclei
Airborne transmission or
droplets from respiratory
secretions of people with
rubella
or
with
subclinical cases of (3050%)

Respiratory tract, direct
contact or inhalation of
aerosols from skin
lesions of a person that
has VZV
Fecal-oral route and at
times the oral-oral route

Below is a list of complications of these diseases.
Disease

Complications

HBV

Chronic infection and malaise/fatigue for weeks and /or months. There
are over 200 million carriers worldwide. Overall case-fatality rate of
1,000-1500 per year in the United States which is due to HBV related
liver carcinoma. 200-300 fatalities a year from fulminant disease and
250,000 fatalities a year worldwide are due to HBV liver disease. The
cause of 80 percent of hepatocellular carcinomas and is second only to
tobacco use regarding known human carcinogens.

Diphtheria

Usually due to the effects of the toxin, and include myocarditis, neuritis,
otitis media, respiratory insufficiency and death. Overall case-fatality
rate is 5-10 percent and up to 20 percent in children under five years of
age.

Tetanus

Laryngospasm, fractures of the spine or long bones, hyperactivity of the
autonomic nervous system, nosocomial infection especially pulmonary
embolism, aspiration pneumonia and death.

Pertussis

Seizures and encephalopathy. In unimmunized populations the case
fatality rate are more than 300,000 deaths annually.

Hib

Meningitis, epiglottitis, pneumonia, arthritis, cellulitis, osteomyelitis and
bacteremia. Others experience hearing impairment or neurologic
sequelae and death can occur. Over-all case fatality rate is 2-5 percent.

Measles

Diarrhea, otitis media, pneumonia, subacute sclerosing panencephalitis
(SSPE) and encephalitis. When a woman has measles and is pregnant,
complications can result in premature labor, spontaneous abortion and
low birth weight infants. Pneumonia accounts for 60 percent of the
deaths. Death is greater in children under five years of age and adults
over 20 years of age.

Mumps

CNS involvement; orchitis, oophoritis, myocarditis, pancreatitis, and
deafness and death. Over-all case fatality rate 1-10 per 10,000 cases.

Rubella

Over-all case fatality rate in 1964 included 2,100 neonatal deaths and
11,250 abortions (both surgical and spontaneous). Other complications
included 2,000 cases of encephalitis. The infants with CRS were noted
to be deaf, blind and mentally retarded.

Varicella

Secondary bacterial infections, pneumonia, central nervous system
symptoms and Reye’s syndrome. If a woman is pregnant and develops
maternal Varicella between five days before and two days after delivery
the neonate has a 30 percent fatality rate. Prior to five days before
delivery the neonate will usually not have any complications. Over-all
case fatality rate is 1 per 60,000 cases. Adults have a 35 percent
mortality rate however; this represents only 5 percent of the cases.
People that are immunocompromised have a 36 percent mortality rate.

Polio

Case fatality rate is 2-5 percent in children, 15-30 percent in adults. In
1952 there were more than 21,000 paralytic cases reported.

AHCCCS Annual Immunization Assessment, Contract Year 2001

2

Risk of Complications from Disease vs. Risk of Adverse Reactions from Vaccines
No vaccine is perfectly safe or effective. Approximately 10,000 cases of adverse health effects are
reported to the CDC through the Vaccine Adverse Event Reporting System (VAERS) each year.
Research is under way by the U. S. Public Health Service to better understand which vaccine adverse
events are truly caused by vaccines (or are coincidental to their administration) and how to reduce the
already low risk of serious vaccine-related injury.
Children are far more likely to be injured by a vaccine-preventable disease than by the vaccine. Still,
some parents refuse to have their children immunized because of the possiblity of adverse reaction to
a vaccine. Of the 6,329 cases in the final total sample for the 2001 AHCCCS immunization
assessment, 27 (0.4 percent) parent refusals were documented and these cases were excluded from the
total sample size.
Below is a comparison of risks from disease and risks from vaccines.
Disease

Vaccine

Measles
Pneumonia = 1 in 20
Encephalitis 1 in 2,000
Death = 1 in 3,000

MMR
Encephalitis or severe allergic reaction
= 1 in 100,000

Mumps
Encephalitis = 1 in 300
Rubella
Congenital Rubella Syndrome = 1 in 4 (if a
woman becomes infected early in pregnancy)
Diphtheria
Death = 1 in 20
Tetanus
Death = 3 in 100

DTP
Continuous crying, then full recovery = 1 in 100
Convulsions or shock, then full recovery =
1 in 1,750
Acute encephalopathy = 0-10.5 in 1,000,000
Death = none proven

Pertussis
Pneumonia = 1 in 8
Encephalitis = 1 in 20
Death = 1 in 200
Source: Centers for Disease Control and Prevention, Epidemiology and Prevention of Vaccine-Preventable Diseases, sixth
edition (second printing), January 2001

AHCCCS Annual Immunization Assessment, Contract Year 2001

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