Use of Quarantine to Control an Import-Associated Outbreak of Measles in a Rural Religious Community – North Carolina, 2013

BACKGROUND:  In April, 2013, a measles outbreak began when an unvaccinated traveler developed illness after returning from India to a largely unvaccinated Hare Krishna community in rural North Carolina. Although current guidelines suggest that the use of quarantine may be impractical for controlling the spread of measles in communities, a relatively large-scale quarantine of exposed, susceptible individuals was employed to limit the spread of disease.  Concurrent with preferred methods of control, such as pre- and post-exposure vaccination strategies, quarantine was initiated for all exposed, susceptible contacts. We describe the use of quarantine and other control measures used by local public health departments in response to this outbreak.

METHODS:  We worked with all local health departments affected by the outbreak to identify contacts and the number of persons to whom isolation orders or quarantine orders were issued. We calculated the number of measles-mumps-rubella vaccine (MMR) doses administered and the number of high-risk contacts to whom immune globulin (IG) was administered.    

RESULTS:  A total of 23 cases of measles were identified with onsets ranging over a 32-day period (April 5 – May 7). Isolation orders were issued to 30 persons, including 22 case-patients and 8 persons in whom measles infection was initially suspected but later ruled out. During the outbreak, 1,049 persons were identified as contacts.  MMR was administered to 184 susceptible contacts and 13 high-risk persons received IG for post-exposure prophylaxis. Eighty-nine (8%) contacts from 8 counties in North Carolina were issued quarantine orders based on inability to provide proof of immunity to measles and failure to receive MMR vaccine within 72 hours of exposure.  Of the 89 quarantine orders issued, 72 (81%) were written orders and 17 (19%) were verbal.  Compliance with quarantine orders was not monitored, however there were no reported instances of non-compliance or need for additional enforcement measures.  

CONCLUSIONS:  This import-associated measles outbreak required extensive public health interventions throughout many communities in North Carolina. Although often considered impractical in community settings, quarantine was widely used during this response. The contribution of widespread quarantine to the rapid resolution of this outbreak is difficult to quantify. However, the lack of operational obstacles or reported issues with compliance suggests that quarantine should be considered as a control measure in future outbreaks.