Active and Direct Active Monitoring of Travelers Returning from Countries that Experienced Widespread Transmission of Ebola Virus Disease, Rhode Island, October 2014-December 2015.

BACKGROUND Ebola Virus Disease (Ebola) is a viral hemorrhagic fever that causes severe illness and can be fatal. Symptoms present 2 to 21 days after exposure to the Ebola virus and include: sudden onset of fever, severe headache, muscle pain, weakness, and fatigue, followed by vomiting, diarrhea, abdominal pain and unexplained bleeding or bruising.1 In December 2013, an outbreak of Ebola began in Guinea and by March 2014 cases were reported in neighboring Liberia and Sierra Leone.2,3 Within months, this outbreak rapidly progressed to become the largest in the history of the disease. Though the outbreak was concentrated in Liberia, Guinea, and Sierra Leone, cases were imported into seven other countries, including the United States.4 An imported case of Ebola in a traveler from Liberia was reported in Dallas, Texas in September 2014. Subsequently, two healthcare workers who cared for this individual developed Ebola. In October 2014, the New York City Department of Health and Mental Hygiene reported an imported case of Ebola in a physician who had recently returned from Guinea.5 In response to the threat of imported Ebola cases, the Centers for Disease Control and Prevention (CDC) implemented a number of control measures through the Division of Global Migration and Quarantine.6 The CDC and the U.S. Customs and Border Protection began enhanced entry screening for individuals entering the U.S. from Liberia, Guinea, and Sierra Leone in mid-October 2014 (Mali was briefly added from November 2014 to January 2015).7,8 The Department of Homeland Security subsequently required all passengers flying from an Ebola-affected country to arrive in the U.S. at one of five designated airports for entry screening. On October 27, 2014, the CDC released the Interim U.S. Guidance for Monitoring and Movement of Persons with Potential Ebola Virus Exposure for the post-arrival monitoring of travelers from Ebola-affected countries by state and local public health departments.9,10 This document recommended that these travelers be monitored for 21 days after their last potential exposure to Ebola virus (21 days being the longest incubation period). The Rhode Island Department of Health (RIDOH) immediately incorporated these guidelines into its traveler monitoring program.