BACKGROUND:
In July 2003, Illinois Department of Public Health decided the quickest and most cost effective path to delivering a web-based immunization registry was to modify a Public Domain system instead of building a new application.

OBJECTIVE:
To deploy a web-based immunization registry (I-Care) for Illinois using an existing application in the public domain and customizing it to fit the needs of the State of Illinois.

METHOD:
Using the Ohio IMPACT Statewide Immunization Information System (SIIS) as a foundation to build upon, the Illinois Department of Public Health has taken that two-tiered system and redesigned it into a more robust application using the Microsoft .NET architecture and Oracle 9i. The original system was broken out into three separate pieces; the static data layer (Oracle 9i), the presentation layer (Microsoft IIS), and the business logic layer. Since Illinois is a “non-consent” state, the Label Security feature of Oracle 9i will be used to prevent access to unconsented records in the database. To create the business logic layer the original .asp (Active Server Pages) program logic was divided into reusable web controls, XML web services, and other object types and classes using Microsoft VB .NET, and C# (C Sharp) programming languages. The second phase of this system will include the integration of a vaccine warehousing solution.

RESULT:
The I-Care registry is a “new”, feature rich application developed to the specifications of the Illinois Department of Public Health. By using IMPACT SIIS as a free foundation the Department has been able to both shorten the development lifecycle as well as save more than $300,000 in development costs.

CONCLUSION:
As a result of using an existing application as a framework to build on, it is more cost effective and timely than building from the ground up. This new 3-Tier system allows for the independent scaling of either of the tiers depending on performance requirements.

LEARNING OBJECTIVES:
1. Public domain software is a very cost effective option with quick turnaround.
2. The system delivered is customized for the specific needs of the State