Write a 2-to-3 page summary paper (Not including the cover & Reference pages) that
1. Summarizes ARTICLE TWO in the resources-2. US Federal Travel Restrictions for Persons with Higher-Risk Exposures to Communicable
Diseases of Public Health Concern
Laura A. Vonnahme, M. Robynne Jungerman, Reena K. Gulati, Petra Illig, Francisco Alvarado-Ramy
Published guidance recommends controlled movement for persons with higher-risk exposures (HREs) to communi- cable diseases of public health concern; US federal public health travel restrictions (PHTRs) might be implemented to enforce these measures. We describe persons eligible for and placed on PHTRs because of HREs during 20142016. There were 160 persons placed on PHTRs: 142 (89%) in- volved exposure to Ebola virus, 16 (10%) to Lassa fever virus, and 2 (1%) to Middle East respiratory syndrome coro- navirus. Most (90%) HREs were related to an epidemic. No persons attempted to travel; all persons had PHTRs lifted after completion of a maximum disease-specific incuba- tion period or a revised exposure risk classification. PHTR enforced controlled movement and removed risk for dis- ease transmission among travelers who had contacts who refused to comply with public health recommendations. PHTRs are mechanisms to mitigate spread of communi- cable diseases and might be critical in enhancing health security during epidemics.
n August 2014, the World Health Organization declared the Ebola virus disease outbreak in West Africa a public health emergency of international concern. In response to this outbreak, the Centers for Disease Control and Preven- tion (CDC) published Interim U.S. Guidance for Monitor- ing and Movement of Persons with Potential Ebola Virus Exposure, known as the Monitoring and Movement Guid- ance (1). This guidance recommended controlled move- ment, which was defined as limitation of long-distance travel by commercial means, for persons with higher-risk exposures (HREs), which were defined as having had a high-risk exposure to Ebola virus on the basis of epide- miologic risk factors or close contact with a person with
Author affiliations: Centers for Disease Control and Prevention, Atlanta, Georgia, USA (L.A. Vonnahme, P. Illig,
F. Alvarado-Ramy); Centers for Disease Control and Prevention, Reston, Virginia, USA (M.R. Jungerman); Centers for Disease Control and Prevention, Seattle, Washington, USA (R.K. Gulati)
DOI: https://doi.org/10.3201/eid2313.170386
symptomatic Ebola for a prolonged period who was not using appropriate personal protective equipment (1,2). In addition, in March 2015, CDC published revised criteria for use of federal public health travel restrictions (PHTRs) in the Federal Register so that these tools could be used to prevent travel of persons exposed to a communicable disease of public health concern and to support enhanced public health response to communicable disease outbreaks (Table 1) (3).
CDC uses federal PHTRs to protect the traveling public by preventing commercial air travel or other means of international travel across US borders of persons with a communicable disease or at risk for development of a disease that poses a public health threat (3,4). Federal mechanisms used to implement travel restrictions include the public health do not board (DNB) and Public Health Lookout lists (5,6). The DNB tool was developed in 2007 to prevent persons who met criteria (Table 1) from board- ing commercial flights of any duration that have depar- tures to or from the United States (5,6). A Public Health Lookout list is issued to complement the DNB, notifying US Customs and Border Protection (CBP) officers who subsequently notify CDC when a person on PHTR at- tempts to enter the United States at any port of entry (i.e., seaport, airport, or land border) (7). Federal PHTRs are typically not applied to domestic travel on trains, buses, or ships because the mechanism for verifying travelers on these conveyances is different than that of the robust, ex- isting system for commercial air travel and international travel across US borders.
Federal PHTR can be considered for any persons with a suspected or confirmed disease of public health interest or a HRE to a communicable disease that poses a public health threat should the person become symp- tomatic during travel (5). Before the Ebola virus disease outbreak in 2014, PHTRs had only been used for persons with suspected or confirmed infectious pulmonary tuber- culosis (99%) or confirmed measles (6) and not for per- sons at risk for development of a disease of public health
Travel Restrictions and Communicable Diseases
Table 1. Criteria for placement on and removal from federal public health travel restrictions, March 2015*
Criteria for placement Criteria for removal
Be known or likely infectious with, or exposed to, a communicable disease that
poses a public health threat
AND meet 1 of the following 3 criteria
1)Be unaware of diagnosis, noncompliant with public health recommendations,
or unable to be located OR
2)be at risk for traveling on a commercial flight, or internationally by any means
OR
3)travel restrictions are warranted to respond effectively to a communicable
disease outbreak or to enforce a federal or local public health order.
*Criteria were obtained from the Centers for Disease Control and Prevention (3).
Proven noninfectiousness or no longer being at
risk for becoming infectious (by documented laboratory confirmation, lapse of known period of infectiousness, or lapse of incubation period without development of symptoms)
interest. Under the revised criteria for federal PHTRs, and in conjunction with the Monitoring and Movement Guid- ance in place during the 20142016 Ebola epidemic (1), persons with HRE to Ebola virus were eligible for federal PHTR (3).
In addition, persons with HREs to other communicable diseases that posed a public health threat were also eligible for DNB placement. Thus, CDC considered and applied PHTR to persons with HREs to Lassa fever virus and Mid- dle East respiratory syndrome coronavirus (MERS-CoV). These contacts were monitored by occupational health or local or state health departments. Travel restrictions were not considered for contacts of 2 patients with cases of in- fection with MERS-CoV imported into the United States in 2014 (8). Guidance for use of controlled movement for an exposure to MERS-CoV, including use of federal PHTR, has been published (9). To illustrate how travel restrictions might protect the health of the traveling public and contrib- ute to enhanced global health security, we describe persons with HREs to a communicable disease of public health interest who were eligible for and placed on PHTR during 20142016.
Methods
CDC maintains case records for persons for whom federal PHTRs are requested in its Quarantine Activity Report- ing System, a secure, restricted-access database (10). De- mographic, clinical, and exposure information is obtained from the requesting agency, typically a local or state health department, as well as evidence that the criteria for implementing and removing PHTR are met and the dates and times of major events leading to placement or remov- al of federal PHTR. We identified all persons placed on federal PHTRs because of HREs to any communicable disease of public health concern during a 3-year period (20142016); persons whose travel was restricted because of a confirmed or suspected communicable disease have been reported elsewhere (6,7) and were excluded from this analysis.
For all identified persons, we examined demographics
including sex, age, and location at time of PHTR placement
(i.e., within or outside the United States). We determined the circumstances of the exposure (high-risk or close contact) and the type of contact the person had with the case-patient with the communicable disease (i.e., health- care, household, or community exposure). In addition, we described the circumstances under which persons were removed, either related to the disease-specific incubation periods or a revised exposure risk classification based on reassessment or a change in guidance, and the number of days spent under PHTR. This record review and analysis was determined by CDC to be Public Health Practice: Non- Research and therefore not subject to review by the CDC Institutional Review Board.
Results
In the 3-year cohort time frame, all restrictions for persons exposed to a communicable disease of public health concern were implemented during a 1-year pe- riod (August 2014July 2015); a total of 164 persons were considered eligible for federal PHTR as a result of exposure to Ebola virus, Lassa fever virus, or MERS- CoV. Exposures to Ebola virus and MERS-CoV were related to an ongoing epidemic of those diseases. Of persons eligible, 160 (98%) were placed under PHTR: 142 (89%) persons were exposed to Ebola virus in the United States or West Africa, 16 (10%) were contacts of a confirmed case-patient with Lassa fever imported into the United States, and 2 (1%) were exposed to MERS- CoV during an outbreak in South Korea (Table 2). Four (3%) persons were not placed under PHTR because of imminent ending of the monitoring period for the patient or insufficient identifying information needed for place- ment on PHTR. Most (154, 96%) persons were located in the United States at the time of placement. Median age was 38 years (range 5 months72 years); 49 (31%) were male, and 84 (52%) were female. Sex was not re- ported for 27 (17%) contacts.
Of those placed under PHTR, 136 (85%) were re- moved after completion of the incubation period (14 days for infection with MERS-CoV, 21 for Ebola and Lassa fever) on the basis of the last day of exposure and after
Emerging Infectious Diseases www.cdc.gov/eid Vol. 23, Supplement to December 2017 S109
PREVENT
Table 2. Characteristics of persons placed on federal public health travel restrictions because of higher-risk exposure to a
communicable disease or pathogen of public health concern, January 2014December 2016*
Characteristic Ebola Lassa fever MERS-CoV Total
No. contacts identified 142 16 2 160
Median age, y (range) 38 (071) 39 (169) 51 (3972) 38 (072)
Sex
M 44 4 1 49 (31)
F 72 11 1 84 952)
Not reported 26 1 0 27 (17)
Location at time of placement
United States
138
16
0
154 (96)
Outside continental United States 4 0 2 6 (4)
*Values are no. (%) persons except as indicated. MERS-CoV, Middle East respiratory syndrome corona virus.
confirmation that they remained asymptomatic. Another 20 (13%) were removed because of a revised exposure risk classification after a change in guidance, and 4 (2%) were removed because of a revised exposure risk clas- sification based on reassessment. Ebola contacts were on PHTR for an average of 12 days, MERS-CoV contacts 9 days, and the Lassa fever contacts 13.5 days. None of the persons on PHTR attempted to travel into, out of, or within the United States.
Persons Exposed to Ebola in the United States
Most (128, 88%) persons eligible for PHTR for an Ebola exposure were exposed to 1 of 4 cases of Ebola virus dis- ease identified in the United States: 2 imported cases and 2 locally acquired cases (1113) (Table 3). During Octo- ber 7November 2014, a total of 124 (97%) contacts were placed on PHTR (Figure).
The state health department (SHD) of jurisdiction identified 53 contacts for the first Ebola case-patient, who had traveled from Liberia to the United States before be- coming symptomatic. Controlled movement was indicated for all contacts, and 50 (94%) were subsequently placed on PHTR; 3 (6%) contacts were not placed on PHTR because their 21-day monitoring period was scheduled to end 1 day after they were identified as needing travel restrictions. Of the 50 contacts who were placed on PHTR, 49 (98%) were healthcare workers who were assessed as high-risk contacts because of an unidentified breach in infection control in the healthcare facility where the first case-patient was treated.
One community contact was considered to have had close contact with the case-patient. This contact was placed on PHTR because the person had imminent travel plans but could not be located, and it was unknown whether the per- son was symptomatic. None of the 50 contacts showed de- velopment of symptoms of Ebola.
Two healthcare workers who provided care to the first case-patient became the second and third confirmed Ebola case-patients in the United States (11,12). Two SHDs identified 72 contacts who were eligible for PHTR because of their potential exposure to Ebola: 24 contacts of the second case-patient and 48 contacts of the third case-patient. A total of 71 (99%) persons were placed un- der PHTR; 1 person was not placed because of insufficient identifying information.
Of persons placed on PHTR, 37 (52%) were high-risk contacts and 34 (48%) were identified as having close con- tact. Among high-risk contacts, 31 (84%) were healthcare workers who had provided care to the second or third case- patients and 6 (16%) were community contacts. Of the 34 contacts initially identified as having close contact, 24 (71%) were removed from PHTR within 1 h after it was determined that their exposure risk classification had changed. Of these 24 contacts, 4 were reclassified after further epidemiologic assessment, and 20 were reclassified after revision of the risk classification guidelines (14). Of the contacts for the second and third case-patients who remained on PHTR for the du- ration of their incubation periods (47, 66%), none showed development of symptoms of Ebola.
Table 3. Types of contacts, by risk level, identified for federal travel restrictions because of exposure to 4 case-patients given a
diagnosis of Ebola in the United States, October 7November 14, 2014*
Case-pa tient 1 Case-pa tient 2 Case-p atient 3 Case-pa tient 4 Total
Risk level
High risk Close contact
High risk Close contact
High risk Close contact
High risk Close contact
No. contacts identified 52 1 24 0 14 34 3 0 128
Household contact 0 0 0 0 0 0 1 0 1
Healthcare exposure 51 0 23 0 8 0 0 0 82
Community contact 1 1 1 0 6 34 2 0 45
Contacts placed on travel restrictions 49 1 24 0 13 34 3 0 124
*High risk was defined as being within ?3 feet (1 m) of a person with symptomatic Ebola for a prolonged period while not using appropriate personal
protective equipment.
Includes 20 contacts with persons on airplanes.
Two healthcare workers and 1 community contact with an exposure to case-patient 1 were not placed on travel restrictions because their 21-d incubation periods were scheduled to end 1 day after they were to be placed under travel restrictions. One community contact exposed to case-patient 3 was not placed on travel restrictions because of insufficient biographical data needed for placement.
