Key points
- Measles is nationally notifiable, and cases should be reported to the appropriate health department.
- Surveillance and prompt investigation of cases and contacts help to stop the spread of measles.
Measles in the United States
The highly contagious measles virus is often brought into the United States by travelers or people from other countries. Each imported measles case could start an outbreak, especially if undervaccinated groups are exposed. Surveillance and prompt investigation of cases and contacts help to stop the spread of disease.
Case definition
Measles cases are reported by states to CDC through the National Notifiable Diseases Surveillance System (NNDSS). Both probable and confirmed cases should be reported nationally.
Cases and outbreaks
Measles is nationally-notifiable and cases should be reported to the appropriate health department. Measles cases are reported by states to CDC through NNDSS.
Surveillance manual
The Manual for the Surveillance of Vaccine-Preventable Diseases provides current guidelines for health department personnel involved in VPD surveillance and response. Learn more about measles case definition, reporting, and investigation.
Measles lab manual
Manual for the laboratory diagnosis of measles and rubella virus infection, 3rd edition, June 2018 from the World Health Organization (WHO)
This Measles & Rubella Laboratory Manual provides information about the WHO Global Measles and Rubella Laboratory Network. It contains detailed protocols for collection and handling of specimens for confirmation of measles and rubella infections. The manual describes both serologic and molecular methods as well as virus isolation. There is also information on biosafety and international shipping regulations. These techniques have been used successfully at for investigation of measles and rubella outbreaks.
Responding to outbreaks
Prompt recognition, reporting, and investigation of measles are important. The spread of the disease can be limited with early case identification; and early public health response including vaccination and quarantine of susceptible contacts without presumptive evidence of immunity. Laboratory confirmation is essential for all measles outbreaks.
State and local health departments have the lead in investigating measles cases and outbreaks when they occur.