MMG Frequently Asked Questions

A: Message mapping guides (MMGs) used in National Notifiable Diseases Surveillance System (NNDSS) describe the data content needed for electronic HL7 case notifications for national notifiable infectious diseases or conditions.

These MMGs include a description of each data element in the case notification as well as the attributes associated with each data element, such as its valid values, whether the data element repeats, and HL7 instructions specific for the data element. Public health jurisdictions use the information in an MMG to package the information in their surveillance system into an HL7 case notification message for Centers for Disease Control and Prevention (CDC).

MMGs are used for each condition or disease that is transmitted to CDC through NNDSS. For many national notifiable diseases, the generic v2 MMG, which includes the basic information needed in every case notification, provides sufficient information while, for others, both the generic v2 MMG and a disease-specific MMG are used.

A: CDC is developing HL7 message mapping guides to improve collection, transmission, and analysis of data needed at the national level for public health surveillance. In doing so, CDC is implementing messaging standards and vocabulary standards used in healthcare. It also provides an opportunity to update the information requested for a disease or condition when the epidemiology of the notifiable disease has changed over time and new data are needed about risk factors or new clinical information is needed, such as laboratory tests and results, vaccination information, and treatment information.

A: A disease-specific message mapping guide is similar to a data dictionary and indicates the data elements (generic or disease-specific) and the valid values for those data elements and how they should be packaged into a case notification. The case notification is the set of information sent on an individual case from the state or local health department for inclusion in the surveillance data systems at CDC.

A: NNDSS works with subject matter experts in CDC programs to prioritize MMGs for development.

Final message mapping guides are available at the Message Mapping Guides page. Guides in development are listed at the bottom of the same page.

Jurisdictions are encouraged to work on implementing these messages and to contact CDC when they are ready to go through the onboarding process to be approved to send case notifications using the messages.

A: MMG development and implementation is a collaborative process that involves multiple teams, both internal and external to CDC. Internal teams include the CDC programs, NNDSS team, messaging and vocabulary team, Message Validation, Processing, and Provisioning System (MVPS) development and testing teams, and implementation and technical assistance team. External groups include health jurisdictions, the Association of Public Health Laboratories (APHL), and the Council of State and Territorial Epidemiologists (CSTE).

CDC deliverables include the message mapping guide, test case scenarios, HL7 test messages, and an annotated case report form. The MMG development and implementation process includes:

1. Requirements analysis.
2. Message design and development.
3. Pilot testing of MMG.
4. Incorporation into MVPS and user acceptance testing.
5. Publication of final MMG.
6. Onboarding jurisdictions to transmit data.

A: The NNDSS Technical Resource Center contains documents for HL7 MMGs and Standards. The Message Mapping Guides page, under the 'In Development' section, contains a list of MMGs that are currently in development. If a guide in development is available for external review by public health reporting jurisdictions or other implementers, the guide's name will contain a hyperlink to the appropriate page and/or documents for review.

A: No. MMGs in development may be revised until they are finalized. Those jurisdictions selected for pilot testing MMGs will be provided with the version of the MMG that should be used in the pilot. All other jurisdictions should wait until final MMGs have been posted to begin implementation.

A: The NNDSS team works with CDC programs, CSTE, and APHL to identify jurisdictions to pilot an MMG. These jurisdictions are selected by using several criteria, including a jurisdiction's technical experience and capacity, readiness and willingness to participate, scalability of their implementation experience, and ability to provide feedback on TA tools and resources.

A: Pilot sites are engaged in several activities:

• Adopting and providing feedback on pilot test-ready MMGs.
• Providing feedback on TA tools and resources.
• Testing and providing feedback on MVPS.

A: For the most up-to-date list of pilot states, please see the chart at the bottom of the monthly Case Surveillance News newsletter at https://www.cdc.gov/nndss/trc/news/.