Measles

• Investigation aims include identifying the source(s) of exposure for any measles cases, as well as identifying other potentially exposed individuals, assessing their immune status, administering post-exposure prophylaxis as indicated, implementing quarantine/exclusion as appropriate, and monitoring them for symptoms through the end of the incubation period for measles at 21 days.
• Additional investigation activities may include assessments of triage and case identification procedures, initiation and compliance with Standard and Transmission-Based Precautions, and ventilation-related processes and control measures.

Measles transmission in healthcare settings is uncommon. Although a measles outbreak in the community is defined as 3 or more related cases, a lower threshold may be used in healthcare settings. 

• A single case of healthcare-associated measles may be considered an outbreak at the facility level.
• Public health agencies can assist with measles investigations and determinations of whether cases were healthcare-associated.
  • In general, determination of healthcare-associated status for measles cases involves determination of epi-linkage to a measles case in a healthcare setting and ruling out other more-likely sources of potential exposure.
• The facility outbreak can generally be considered over when 42 days (two incubation periods) have passed without additional healthcare-associated cases. 

When there is an increase in measles cases in the community, all healthcare facilities should review preparedness measures and ensure maximal staff immunity. CDC publishes tools to aid in healthcare facility preparedness assessments that address key considerations such as documentation of healthcare provider vaccination or presumptive immunity, screening and triage processes, and identification of shared air spaces.