Reporting and Surveillance for Norovirus


Currently, state, local, and territorial health departments are not required to report individual cases of norovirus illness to a national surveillance system. We may not know about many cases because people may not seek healthcare for their illness and most hospitals and doctor’s offices do not generally test for norovirus.

If you suspect an outbreak of norovirus in your community, please contact your state or local health department. Find your state contact.

Healthcare providers should report all outbreaks of acute gastroenteritis, including suspected outbreaks of norovirus, to the appropriate state, local, or territorial health department.

Health departments are encouraged to report all suspected and confirmed norovirus outbreaks through the National Outbreak Reporting System (NORS) and CaliciNet.

Surveillance Systems


The National Outbreak Reporting System (NORS) was launched by CDC in 2009 to collect information on outbreaks of foodborne, waterborne, and enteric (gastrointestinal) disease that spread through contact with infected persons or animals, environmental surfaces, and other or unknown ways. Public health agencies can report all outbreaks of gastroenteritis, including norovirus illness, through this web-based system.

NORS Dashboard is a web-based tool for searching and accessing data from NORS. It has useful graphics that make data easy to visualize. NORS Dashboard helps you learn about reports of outbreaks of foodborne, waterborne, and enteric diseases spread by person-to-person contact, environmental contamination, animal contact, and other means.


CaliciNet is a national norovirus laboratory surveillance network of federal, state, and local public health laboratories in the United States coordinated by CDC. Established in 2009, CaliciNet-certified laboratories collect information on norovirus genotypes associated with gastroenteritis outbreaks in the United States and upload information to a central database. CaliciNet data are updated monthly and can be found here.


CDC established the Norovirus Sentinel Testing and Tracking (NoroSTAT) network in August 2012 for enhanced surveillance of norovirus outbreaks. NoroSTAT is a collaborative network of 12 state health departments and CDC working together to establish and maintain standard practices for norovirus outbreak reporting to CDC surveillance systems. NoroSTAT combines NORS and CaliciNet data.

Other Surveillance Systems

In addition to collecting norovirus outbreak data from state and local health departments, CDC is using the following platforms to generate estimates of norovirus illness and monitor trends over time.

  • New Vaccine Surveillance Network (NVSN) includes study sites that conduct active, population-based surveillance for hospitalizations and outpatient visits associated with acute gastroenteritis in children, as well as surveillance for acute respiratory illness.
  • Foodborne Diseases Active Surveillance Network (FoodNet) is an active surveillance system that collects data on laboratory-confirmed cases of foodborne illnesses, monitors trends in incidence of specific foodborne illnesses over time, attributes illnesses to specific foods and settings, and disseminates this information.
  • The Surveillance Platform for Enteric and Respiratory Infectious Organisms at the VA (SUPERNOVA) is a network of five Veterans Affairs Medical Centers (VAMCs) in the United States that conduct active and passive surveillance for acute gastroenteritis, with laboratory-confirmed testing of various pathogens, including norovirus. SUPERNOVA is an endemic disease surveillance system that provides data to estimate the prevalence and incidence of norovirus in adults. Ongoing surveillance using this platform will allow for characterization of the pathogen distribution and serologic response over time.
  • NoroSurv is a global pediatric norovirus strain surveillance network. The aim of the network is to collect data on the circulating norovirus genotypes in hospitalized children under 5 years of age across different countries and continents. NoroSurv uses the most recent dual [polymerase (P) and capsid (C)] typing nomenclature for norovirus strains. Participating laboratories use standardized protocols for norovirus dual typing to generate P and C types.