Immunization Information Systems


​​​​Immunization Info​rmation Systems​

Updated July 2018

Immunization information systems (IISs), otherwise known as registries, are confidential, population-based, computerized databases that record all immunization doses administered by participating providers to persons residing within a given geopolitical area. They offer an opportunity for confidential, secure, centralized, and immediate access to immunization records for authorized providers.

What Are Immunization Information Systems, and Why Do We Need Them?

IISs offer health care professionals an opportunity to provide up-to-date immunization records to patients, parents, and other health care professionals. IISs can be useful in identifying underimmunized children, as well as monitoring immunization rates for a community.

How You Can Benefit ​from Using an IIS in Your Practice*

Use of a fully functional IIS can:

  • Improve patient care
  • Facilitate work flow
  • Help pediatricians manage costs of providing immunization services
  • Assist with patient recall efforts
  • Aid in decreasing missed opportunities to immunize
  • Improve patient immunization rates and practice HEDIS scores which may be tied to Pay For Performance (P4P) programs
  • Decrease vaccine administration errors using logic programs
    • Resulting in significant cost and time savings by avoiding inappropriate dosing of vaccines
  • Upload and download immunization history for patients
  • Allow for a core component of the pediatric medical history to be truly portable and follow the patient regardless of service location.
    • This creates savings by decreasing or even eliminating chart pulls
    • And eliminates the difficulties and costs of coordinating point to point immunization record transfers between service providers.
  • Provides costs savings for pediatric practices migrating from paper charts to electronic health records,
    • The ability to electronically import patient immunization records from the IIS to the electronic chart generates tremendous cost savings in terms of eliminating data entry time and improves the accuracy of such record conversion. 

*From the AAP State Level Advocacy for IIS Web Page. The expense of submitting immunization data to IISs is currently included in the AMA Current Procedural Terminology (CPT) description and RVU practice expense valuation as a means of covering the cost for immunization providers to fully participate in IISs.

Are There Common Standards for Immunization Information Systems?

The American Immunization Registry Association (AIRA) is a national nonprofit organization whose mission is to "promote the development and implementation of immunization information systems…as an important tool in preventing and controlling vaccine preventable diseases." It has outlined 27 functional standards that an effective IIS should meet. The standards are available at: or 

What Information Is Entered Into an Immunization Information System, and How Is It Protected?

Required elements are critical for record exchange purposes, client deduplication, vaccine management, immunization status evaluation, reminder / recall and data analysis or use purposes. They include:

  • the patient's first, middle, and last name;
  • date of birth;
  • sex;
  • race;
  • ethnicity;
  • birth order;
  • birth state/country; and
  • mother's first, middle, last, and maiden name;
  • vaccine type;
  • vaccine manufacturer;
  • vaccination date; and
  • vaccine lot number.

Optional core data elements are less important for record exchange. Some optional items (e.g., address) may be useful only at the local level. Examples of optional core data elements include (but are not limited to):

  • the patient's alias;
  • address;
  • phone number;
  • social security number;
  • father's name;
  • vaccine provider;
  • and VFC program eligibility.

State law requires that information in the IIS be kept confidential, though reporting of immunizations to an IIS are exempt from the Health Insurance Portability and Accountability Act of 1996 (HIPAA) Privacy Rule since it is considered a public health activity. IISs must protect the privacy of all users, including children, families, and providers. According to standards set by the CDC, all IISs are required to have a written privacy policy that clearly defines notice of inclusion in the IIS, access, to, and use and disclosure of IIS data. For more information, ask the IIS in your ​area for a copy of their confidentiality policy.

How Do Immunization Information Systems Benefit Patients and Their Families?

The benefits for patients and their families are practical and could potentially be lifesaving. An IIS can:

  • Provide the most up-to-date immunization records for personal safekeeping, schools, child care, and sports teams.
  • Provide families with their child's immunization records.
  • Save time and money by ensuring that patients get only those immunizations that are needed.

How Do Immunization Information Systems Benefit Health Care Professionals?

The benefits to a practice can be varied and extensive. An IIS can:

  • Save money by maximizing staff time and reducing paperwork.
  • Provide easily accessible and reliable information on a patient's immunization status.
  • Generate cheap and accurate records for patients, schools, and child care.
  • Assist in managing vaccine inventories.
  • Assist in immunization recall situations.
  • Supply direct information on your practice's immunizations rates, including information required for Healthcare Effectiveness Data and Information Set collection.

Where Can I Find Information About My State's Immunization Information System (IIS)?

The CDC has contact information on its IIS State/Territory/Registry Staff—Main and Technical Contacts page

IIS Resources:


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