NNDSS Communication Evolves to Meet Data Modernization Goals


A multidisciplinary team from CDC took on a year-long project to modernize the communication strategy for the National Notifiable Diseases Surveillance System (NNDSS) for next-generation case surveillance. CDC conducts case surveillance through the National Notifiable Diseases Surveillance System (NNDSS). In the case surveillance process, about 3,000 health departments gather and use data on disease cases to protect their local communities.

Responsive web design

The team:

  • analyzed audience insights,
  • redesigned the NNDSS website,
  • decommissioned old technology,
  • optimized NNDSS’s digital content for search engines,
  • rebranded the NNDSS newsletter,
  • generated new content explaining the value of case surveillance, and
  • conducted media outreach.

This project resulted in improvements in key web metrics, cost savings, and streamlined processes. The team improved CDC’s ability to reach state, territorial, and local health departments using technical resources to help them advance data modernization. The project also increased understanding among non-technical audiences of how CDC collects, shares, and uses case surveillance data to protect the nation’s health.

Full Story

Public Health Problem

Case surveillance is foundational to public health practice. It helps us understand diseases and their spread to determine appropriate actions to control outbreaks. Case surveillance occurs each time public health agencies at the local, state, or national levels collect information about a case—a person diagnosed with a disease or condition—to help prevent serious health threats to Americans. During the COVID-19 response, CDC needed to quickly share technical resources with jurisdictions to help them with the complex task of modernizing their case surveillance systems. At the same time, CDC also needed to use plain language to explain the importance of complex case surveillance data and data systems to decision makers and the public.

A multidisciplinary team from the Center for Surveillance, Epidemiology, and Laboratory Services (CSELS) and its Division of Health Informatics and Surveillance (DHIS) took on a year-long project to modernize the National Notifiable Diseases Surveillance System (NNDSS) communication strategy. The project provided jurisdiction health departments with important resources to advance data modernization; increased understanding of how CDC collects, shares, and uses case surveillance; and showed the value of case surveillance data to our nation’s health.

Actions Taken

interactive map

Project goals included streamlining web content and improving navigation; ensuring that messaging resonated with audiences; increasing visibility and user experience of websites; using innovative technology to improve site performance and updates; and featuring case surveillance data in success stories, social media, and national media.

The team focused its messaging to the needs of each audience, redesigned its digital strategy and technology, and conducted national media outreach.

Specific actions included the following:

Implemented a modern web presence for NNDSS that receives hundreds of thousands of page views by tens of thousands of visitors per month.

  • Used audience insights to understand what people need to know when visiting the NNDSS website.
  • Performed a search engine optimization analysis (how people find the site from search engines) to make the site more visible in search rankings.
  • Executed a content audit to identify content to revise or remove.
  • Analyzed messaging for plain language using the CDC Clear Communication Index and readability tools.
  • Evaluated the structure of the NNDSS website and applied new technologies to improve site users’ experience and make managing the website more efficient.
  • Accelerated web content publishing using the latest web publishing technologies to give CDC experts direct control over content edits.
  • Improved accessibility of web content for people with disabilities using the Web Content Accessibility Guidelines international standard and CDC accessibility guidelines.
  • Redesigned and rebranded the NNDSS newsletter into Case Surveillance News to focus on new information that readers need and drive them to website content.
  • Developed an innovative, interactive, online map to show the status of jurisdictions piloting, onboarding, or in production for sending data about specific diseases to NNDSS.
  • Created success stories showing the value of case surveillance data using a “bite, snack, meal” format so leadership, policy, and communication staff could easily use various content sizes for specific audiences.
  • Conducted media outreach about case surveillance data for the COVID-19 response and how case surveillance supports the CDC Data Modernization Initiative (DMI) in high-profile media outlets.
  • Collaborated with partners such as the Council of State and Territorial Epidemiologists and the Association of Public Health Laboratories to reach NNDSS audiences through social media.
  • Featured case surveillance data on CDC’s COVID Data Tracker, a one-stop-shop for CDC’s COVID-19 data.


Despite also working on the COVID-19 response, the team redesigned all NNDSS communication content and digital spaces and launched a new NNDSS website in April 2021. Impacts include:

  • Saw a 104% increase in home page views and 74% increase in unique visitors to the home page when comparing 2021 and 2020.
  • Increased key web metrics for the NNDSS eSHARE webpage, a critical monthly webinar series that educates public health jurisdictions on the latest NNDSS developments. When comparing 2020 and 2021, page views increased 240%, unique visitors increased 195%, and number of downloads increased 71%.
  • Increased key web metrics for the NNDSS message mapping guide webpage, which provides critical technical tools, resources, and guidance to jurisdictions sending case surveillance data to CDC. When comparing 2020 and 2021, page views increased 80% and unique visitors increased 47%.
  • Increased key web metrics for the rebranded Case Surveillance News Total number of clicks to links in the newsletter increased 92% and average open rate increased 10% to achieve an open rate of 34%, an industry top-tier score.
  • Retired obsolete web technology, as well as additional savings from more efficient use of staffing resources.
  • Streamlined website issue tracking and processes for updating complex case definitions, resulting in more efficient use of web staffing resources.
  • Improved several critical areas of CDC Digital First web best practices, including content readability, intuitive navigation, consistent design, web accessibility, and search engine optimization.
  • Launched a diverse group of stories highlighting the value of case surveillance data to public health.

The multidisciplinary team systematically reviewed all agency case surveillance communication products, digital space, and technology. The team incorporated best practices in communication science and applied modern technologies for website design. The new website appealed to high-level policy and decision makers while improving navigation for technical users, who rely on it for disease surveillance. The rebranded NNDSS newsletter highlighted a wide range of case surveillance content with a streamlined layout and interactive features.

The new case surveillance communication content and website were essential for DHIS, CSELS, and COVID-19 response leadership in promoting the importance of these data. Media interviews publicized critical public health messages and brought national attention to NNDSS. The project enhanced the national communication strategy, advanced CDC DMI goals, and showed case surveillance’s value to the public.

Learn more about how CDC is providing public health departments and partners with the tools and resources they need to develop and implement the next generation of public health data systems.

Page last reviewed: May 13, 2022