Harmful Algal Bloom Surveillance: Integrating a One Health Reporting System into the National Outbreak Reporting System (NORS)

BACKGROUND: The Centers for Disease Control and Prevention (CDC) conducts national surveillance for foodborne and waterborne disease outbreaks and enteric disease outbreaks involving person-to-person, animal contact, environmental contamination, and unknown modes of transmission. Outbreaks are reported to CDC by local and state health departments via the web-based National Outbreak Reporting System (NORS).  Outbreaks associated with exposure to harmful algal blooms (HABs) may be reported. However, HAB-associated outbreaks are difficult to detect and provide insufficient data to inform future prevention efforts. There is no national surveillance system that collects information on single cases of illness or the occurrence of HABs, which are recognized as emerging ecologic issues and indicators of climate change.

METHODS: In 2013, CDC initiated a project to improve surveillance for HABs and associated illnesses. CDC established a HAB working group, a collaboration of state and federal partners with expertise in harmful algal blooms and illness surveillance, to develop a HAB reporting system that will be accessible to local and state health agencies via NORS. The system will utilize a one health approach to collect data—receiving and linking reports of single cases of human illness, animal illness, and HABs.

RESULTS: In 2014, the HAB working group drafted reporting forms for cases of human illness, animal illness, and HABs; and initial case and HAB definitions. Challenges of HAB surveillance identified by the working group included the following:  limited health and environmental standards to inform case and event definitions, limited clinical testing, and limited staff or funding within states to conduct surveillance. The working group identified stakeholders for HAB surveillance who may not currently be involved in outbreak surveillance activities. Programming the system has begun; launch is anticipated in 2015. CDC plans to pilot the system in 2015, with a full launch following user testing and enhancements.

CONCLUSIONS: A national HAB reporting system provides data to understand this emerging issue. CDC has been able to develop a HAB reporting system more quickly by linking the HAB reporting system to NORS and through the HAB working group. Launch and maintenance of the system will require ongoing efforts to support state activities and to demonstrate the value of the data through improved reporting definitions and data use.