Before CDC developed the National Electronic Disease Surveillance System (NEDSS) standards, CDC developed and implemented the National Electronic Telecommunications System for Surveillance (NETSS). The term NETSS refers to a computerized public health surveillance information system that allowed health jurisdictions to collect and transmit weekly data regarding nationally notifiable diseases to CDC. Although this system is no longer in use, the term is still used to refer to a proprietary data file format sent to CDC. A bare-bones approach for providing basic data and information, the NETSS file content has not been updated substantially since it was launched in 1990. Although all jurisdictions currently use more robust, integrated surveillance information systems that comply with the NEDSS standards, the NETSS format is still used for transmission of some surveillance data to CDC.
Although the NETSS file format has changed little since 1990, the NEDSS standards are flexible enough to be updated as healthcare and technology evolve. For this reason, NEDSS-compatible systems, including the NEDSS Base System, allow health departments to adapt to changes in laboratory tests and vaccinations, automate data processing, and receive reportable disease data electronically from laboratories and other disease reporters.