Emerging Infectious Diseases Volume 21 Issue 11

2015·8.2 MB·English

by  CDC

Peer-Reviewed Journal Tracking and Analyzing Disease Trends pages 1897–2116
EDITOR-IN-CHIEF
D. Peter Drotman
Associate Editors EDITORIAL BOARD
Paul Arguin, Atlanta, Georgia, USA Dennis Alexander, Addlestone, Surrey, UK
Charles Ben Beard, Ft. Collins, Colorado, USA Timothy Barrett, Atlanta, Georgia, USA
Ermias Belay, Atlanta, Georgia, USA Barry J. Beaty, Ft. Collins, Colorado, USA
David Bell, Atlanta, Georgia, USA Martin J. Blaser, New York, New York, USA
Sharon Bloom, Atlanta, GA, USA Christopher Braden, Atlanta, Georgia, USA
Mary Brandt, Atlanta, Georgia, USA Arturo Casadevall, New York, New York, USA
Corrie Brown, Athens, Georgia, USA Kenneth C. Castro, Atlanta, Georgia, USA
Michel Drancourt, Marseille, France Louisa Chapman, Atlanta, Georgia, USA
Paul V. Effler, Perth, Australia Thomas Cleary, Houston, Texas, USA
David Freedman, Birmingham, Alabama, USA Vincent Deubel, Shanghai, China
Peter Gerner-Smidt, Atlanta, Georgia, USA Ed Eitzen, Washington, DC, USA
Stephen Hadler, Atlanta, Georgia, USA Daniel Feikin, Baltimore, Maryland, USA
Nina Marano, Nairobi, Kenya Anthony Fiore, Atlanta, Georgia, USA
Isaac Chun-Hai Fung, Statesboro, Georgia, USA
Martin I. Meltzer, Atlanta, Georgia, USA
Kathleen Gensheimer, College Park, MD, USA
David Morens, Bethesda, Maryland, USA
Duane J. Gubler, Singapore
J. Glenn Morris, Gainesville, Florida, USA
Richard L. Guerrant, Charlottesville, Virginia, USA
Patrice Nordmann, Fribourg, Switzerland
Scott Halstead, Arlington, Virginia, USA
Didier Raoult, Marseille, France
Katrina Hedberg, Portland, Oregon, USA
Pierre Rollin, Atlanta, Georgia, USA
David L. Heymann, London, UK
Frank Sorvillo, Los Angeles, California, USA
Charles King, Cleveland, Ohio, USA
David Walker, Galveston, Texas, USA
Keith Klugman, Seattle, Washington, USA
Senior Associate Editor, Emeritus Takeshi Kurata, Tokyo, Japan
Brian W.J. Mahy, Bury St. Edmunds, Suffolk, UK S.K. Lam, Kuala Lumpur, Malaysia
Stuart Levy, Boston, Massachusetts, USA
Managing Editor John S. MacKenzie, Perth, Australia
Byron Breedlove, Atlanta, Georgia, USA Marian McDonald, Atlanta, Georgia, USA
John E. McGowan, Jr., Atlanta, Georgia, USA
Copy Editors Claudia Chesley, Laurie Dieterich, Karen Foster, Jennifer H. McQuiston, Atlanta, Georgia, USA
Thomas Gryczan, Jean Michaels Jones, Shannon O’Connor, Tom Marrie, Halifax, Nova Scotia, Canada
Rhonda Ray, Carol Snarey, P. Lynne Stockton Nkuchia M. M’ikanatha, Harrisburg, Pennsylvania, USA
Philip P. Mortimer, London, UK
Production William Hale, Aaron Moore, Barbara Segal, Fred A. Murphy, Galveston, Texas, USA
Reginald Tucker Barbara E. Murray, Houston, Texas, USA
P. Keith Murray, Geelong, Australia
Editorial Assistant Jared Friedberg
Stephen M. Ostroff, Silver Spring, MD, USA
Ann Powers, Fort Collins, Colorado, USA
Communications/Social Media Sarah Logan Gregory
Gabriel Rabinovich, Buenos Aires, Argentina
Mario Raviglione, Geneva, Switzerland
Founding Editor
Joseph E. McDade, Rome, Georgia, USA David Relman, Palo Alto, California, USA
Connie Schmaljohn, Frederick, Maryland, USA
Emerging Infectious Diseases is published monthly by the Centers for Disease Control and Tom Schwan, Hamilton, Montana, USA
Prevention, 1600 Clifton Road, Mailstop D61, Atlanta, GA 30329-4027, USA. Telephone Ira Schwartz, Valhalla, New York, USA
404-639-1960, fax [phone], email [email protected]. Tom Shinnick, Atlanta, Georgia, USA
Bonnie Smoak, Bethesda, Maryland, USA
Rosemary Soave, New York, New York, USA
The conclusions, findings, and opinions expressed by authors contributing
P. Frederick Sparling, Chapel Hill, North Carolina, USA
to this journal do not necessarily reflect the official position of the U.S. Depart-
ment of Health and Human Services, the Public Health Service, the Centers for Robert Swanepoel, Pretoria, South Africa
Disease Control and Prevention, or the authors’ affiliated institutions. Use of Phillip Tarr, St. Louis, Missouri, USA
trade names is for identification only and does not imply endorsement by any of Timothy Tucker, Cape Town, South Africa
the groups named above. Elaine Tuomanen, Memphis, Tennessee, USA
All material published in Emerging Infectious Diseases is in the public John Ward, Atlanta, Georgia, USA
domain and may be used and reprinted without special permission; proper
J. Todd Weber, Atlanta, Georgia, USA
citation, however, is required.
Mary E. Wilson, Cambridge, Massachusetts, USA
Use of trade names is for identification only and does not imply
endorsement by the Public Health Service or by the U.S. Department of Health ∞ Emerging Infectious Diseases is printed on acid-free paper that meets the
and Human Services. requirements of ANSI/NISO 239.48-1992 (Permanence of Paper)
Emerging Infectious Diseases • www.cdc.gov/eid • Vol. 21, No. 11, November 2015
November 2015
On the Cover
Unknown (contemporary).
Cotton canvas, pastel, acrylic, ink. Neurologic Disorders
39 × 59 in. / 99.06 × 149.86 cm. in Immunocompetent
Parque dos Continuadores, Patients with
Maputo, Mozambique.
Autochthonous Acute
Personal Collection,
Hepatitis E. ..................1928
Philip Lederer, USA.
Photograph by David Swerdlow. H.B. Perrin et al.
About the Cover p. 2110 Patients with acute neurologic manifestations
and aminotransferase abnormalities should
Perspective be screened.
Mycotic Infections Acquired
Ebola in West Africa—CDC’s Role
outside Areas of Known
in Epidemic Detection, Control,
Endemicity, United States .........1935
and Prevention ..........................1897
K. Benedict et al.
T.R. Frieden and I.K. Damon
Increased awareness that mycoses can be
Stronger systems are needed for disease
acquired in unusual geographic locations is
surveillance, response, and prevention
needed to promote early diagnosis
worldwide.
and treatment.
Synopses
Use of Internet Search Queries
to Enhance Surveillance of
Uncommon Candida
Foodborne Illness ......................1906
Species Fungemia
G.J. Bahk et al. p. 1977 among Cancer Patients,
“Food poisoning” queries were correlated Houston, Texas, USA ....1942
with the number of foodborne illness–related D.S. Jung et al.
hospital stays. Potentially resistant Candida bloodstream
isolates and use of echinocandins create a
Achievements in and Challenges
need for surveillance of cancer patients.
of Tuberculosis Control in
South Korea ..............................1913 Maternal Effects of Respiratory
J.H. Kim and J.-J. Yim Syncytial Virus Infection
Despite the country’s astounding economic p. 2003 during Pregnancy ......................1951
growth and TB control efforts, TB S.M. Wheeler et al.
incidence remains the highest among Clarifying these effects could show potential
high-income countries. benefits of vaccination of pregnant women.
Ebola Virus Outbreak Investigation,
Sierra Leone, September 28–
November 11, 2014 ...................1921
H.-J. Lu et al.
Knowledge of epidemiologic, clinical, and viral
features of the outbreak is critical for optimizing
control and treatment measures.
Emerging Infectious Diseases • www.cdc.gov/eid • Vol. 21, No. 11, November 2015
Research
Serotype Changes and Drug November 2015
Resistance in Invasive
Pneumococcal Diseases in Carbapenem-Resistant
Adults after Vaccinations in Enterobacteriaceae in Children,
Children, Japan, 2010–2013 .......1956 United States, 1999–2012 .........2014
K. Ubukata et al. L.K. Logan et al.
Pneumococcal conjugate vaccine in children Infections rates have increased in all age
may be associated with penicillin-resistant groups and settings nationally.
Streptococcus pneumoniae in adults.
Contact Tracing Activities
Role of Maternal Antibodies in during the Ebola Virus Disease
Infants with Severe Diseases Epidemic in Kindia and
Related to Human Faranah, Guinea, 2014 ..............2022
Parechovirus Type 3 ..................1966 M.G. Dixon et al.
Y. Aizawa et al. Thorough case identification and contact tracing
Maternal antibodies may protect infants from are necessary to end this epidemic.
severe illness caused by this pathogen.
p. 2049 Association of Higher MERS-CoV
USA300 Methicillin-Resistant Virus Load with Severe
Staphylococcus aureus, Disease and Death,
United States, 2000–2013 .........1973 Saudi Arabia, 2014 ....................2029
M. Carrel et al. D.R. Feikin et al.
We confirm USA300 in the West and Midwest More data are needed to determine whether
and subsequent diffusion to the East Coast. modulation of virus load by therapeutic agents
affects clinical outcomes.
Molecular Epidemiology of
Hospital Outbreak of Middle East No Geographic Correlation
Respiratory Syndrome, Riyadh, between Lyme Disease
Saudi Arabia, 2014 ....................1981 and Death Due to 4
S.F. Fagbo et al. Neurodegenerative Disorders,
United States, 2001–2010 ........2036
A contiguous outbreak was the result of multiple
J.D. Forrester et al.
introductions from outside the hospital.
p. 2075 Death rates for these disorders were not
Climatic Influences on associated with incidence of confirmed Lyme
Cryptococcus gattii Populations, disease cases.
Vancouver Island, Canada,
2002–2004 ................................1989 Dispatches
C.K. Uejio et al.
Warmer temperatures are associated with 2040 Invasive Pneumococcal
decreased populations in soil and on trees. Disease 3 Years after
Introduction of 10-Valent
Coccidioidomycosis among Pneumococcal Conjugate
Workers Constructing Solar Vaccine, the Netherlands
Power Farms, California, M.J. Knol et al.
USA, 2014 .................................1997
J.A. Wilken et al. 2045 Fosfomycin Resistance
in Escherichia coli,
In Coccidioides-endemic areas, more effective
Pennsylvania, USA
exposure-reduction measures are needed.
H. Alrowais et al.
Shigella Infections in
2048 Epidemiology of Primary
Household Contacts of Pediatric
Multidrug-Resistant
Shigellosis Patients in Rural
Tuberculosis, Vladimir Region,
Bangladesh ...............................2006
Russia
C.M. George et al.
J.V. Ershova et al.
Contacts of children with shigellosis are highly
susceptible to infections; high fly counts and
contaminated water increase risk.
Emerging Infectious Diseases • www.cdc.gov/eid • Vol. 21, No. 11, November 2015
2088 Mortality Risk Factors for
Middle East Respiratory
November 2015 Syndrome Outbreak, South
Korea, 2015
2052 Use of Whole-Genome M.S. Majumder et al.
Sequencing to Link
Another Dimension
Burkholderia pseudomallei
from Air Sampling to 2091 Liberia–Moving beyond
Mediastinal Melioidosis, Ebola Free
Australia
H. Keys et al.
B.J. Currie et al.
Letters
2055 Rotavirus P[8] Infections
2093 Mycobacterium sherrisii
in Persons with Secretor
Pulmonary Disease,
and Nonsecretor
Burkina Faso
Phenotypes, Tunisia
S. Ayouni et al.
2094 Histoplasmosis in
HIV-Infected Patients,
2059 RmtC and RmtF 16S rRNA
Yaoundé, Cameroon
Methyltransferase in
p. 2101
NDM-1–Producing
2096 Divergent Gemycircularvirus
Pseudomonas aeruginosa
in HIV-Positive Blood, France
M. Rahman et al.
2098 Co-Infection with Drug–
2063 Serogroup W Meningitis Susceptible and Reactivated
Outbreak at the Subdistrict Latent Multidrug–Resistant
Level, Burkina Faso, 2012 Mycobacterium tuberculosis
L. Cibrelus et al.
2100 Sensitivity to Polymyxin B
2067 Economic Costs of Measles in El Tor Vibrio cholera O1
p. 2107
Outbreak in the Netherlands, Strain, Kolkata, India
2013–2014
2103 G2P[4]-RotaTeq Reassortant
A.W.M. Suijkerbuijk et al.
Rotavirus in Vaccinated Child,
2070 Chikungunya Virus as Cause United States
of Febrile Illness Outbreak,
2105 Multidrug-Resistant
Chiapas, Mexico, 2014
Tuberculosis in Child
T.F. Kautz et al.
Successfully Treated with
9-Month Drug Regimen
2074 Encephalitis-Associated
Human Metapneumovirus
2106 Human Infection with
Pneumonia in Adult, Australia
Sporolactobacillus
A. Fok et al. laevolacticus,
Marseille, France
2077 Workplace Safety Concerns
among Co-workers of Books and Media
Responder Returning from
2109 The Fantastic Laboratory of
Ebola-Affected Country
Dr. Weigl: How Two Brave
B.P. Chan et al.
Scientists Battled Typhus and
Sabotaged the Nazis
2080 Pneumococcal Infection
among Children before About the Cover
Introduction of 13-Valent
Pneumococcal Conjugate 2110 Celebrating the Fabric of
Vaccine, Cambodia Commonplace Society
P. Turner et al.
Etymologia
1905 Ebola
2084 Middle East Respiratory
Syndrome in 3 Persons, Conference Summary
South Korea, 2015
Invasive Salmonella Discussion
J.-S. Yang et al.
in Africa Consensus Meeting,
Blantyre, Malawi
http://dx.doi.org/10.3201/eid2111.150624
Emerging Infectious Diseases • www.cdc.gov/eid • Vol. 21, No. 11, November 2015
Presenting the ongoing challenges
that emerging microbial threats
pose to global health
PERSPECTIVE
Ebola in West Africa—
CDC’s Role in Epidemic Detection,
Control, and Prevention
Thomas R. Frieden, Inger K. Damon
Since Ebola virus disease was identified in West Africa on staff participated in the smallpox eradication program, one
March 23, 2014, the Centers for Disease Control and Pre- of CDC’s most notable international responses and most
vention (CDC) has undertaken the most intensive response intensive technical collaborations with the World Health
in the agency’s history; >3,000 staff have been involved, Organization (WHO) before the current Ebola response (1).
including >1,200 deployed to West Africa for >50,000 per-
CDC had a team of experts on the ground in Guinea
son workdays. Efforts have included supporting incident
within 1 week after the initial case report. When Ebola re-
management systems in affected countries; mobilizing part-
surged and spread, CDC activated its Emergency Opera-
ners; and strengthening laboratory, epidemiology, contact
tions Center (EOC) (2) on July 9, 2014. Since then, CDC
investigation, health care infection control, communication,
has coordinated >1,400 deployments to Guinea, Liberia,
and border screening in West Africa, Nigeria, Mali, Senegal,
and the United States. All efforts were undertaken as part and Sierra Leone and sent staff to help Nigeria (3), Sen-
of national and global response activities with many partner egal (4), and Mali (5) prevent the spread of Ebola. CDC
organizations. CDC was able to support community, nation- staff also have undertaken development of new diagnostic
al, and international health and public health staff to prevent tests (6) and research to evaluate therapeutic drugs (7) and
an even worse event. The Ebola virus disease epidemic vaccine efficacy (8,9). As of mid-2015, >500 CDC staff
highlights the need to strengthen national and international continued working throughout the 3 most heavily affected
systems to detect, respond to, and prevent the spread of
nations (Guinea, Sierra Leone, and Liberia), the West Af-
future health threats.
rica region, and the United States.
At the peak of the epidemic in fall 2014, widespread
The unprecedented epidemic of Ebola virus disease transmission of Ebola virus was occurring in the capitals of
(Ebola) in West Africa highlights the need for stronger Liberia and Sierra Leone; health care systems had become
systems for disease surveillance, response, and prevention largely nonfunctional; Ebola cases or clusters occurred in
worldwide. After a preventable and costly local and global other countries of Africa; and there was a real possibility
delay, heroic efforts by clinicians and public health person- that Ebola could spread widely and become endemic in
nel and organizations from West Africa and throughout the some of the poorest and sickest countries of the world. As
world broke the cycle of exponential growth of the epi- of late 2015, although the region is not Ebola-free, enor-
demic and prevented many deaths. As of late 2015, this re- mous progress has been made. There is a risk for resur-
sponse, conducted at great expense and personal risk, con- gence and cross-border spread, and because the status of
tinues. Here we summarize the experience of the Centers Ebola virus reservoirs is not confirmed and the possibility
for Disease Control and Prevention (CDC), which comple- of sexual transmission from survivors persists, the potential
ments efforts by the affected countries, the international exists for periodic outbreaks.
community, and many partner organizations.
Since Ebola was first reported in West Africa on March CDC Response in Heavily Affected Countries
23, 2014, CDC has undertaken the most intensive outbreak
response in the agency’s history. As of July 2015, >1,200 Incident Management
CDC employees had deployed to the affected countries for One challenge in responding to complex outbreaks is co-
>50,000 person workdays; >3,000 CDC staff, including ordination among partners. CDC’s priority in West Africa
all 158 Epidemic Intelligence Service Officers, have par- during summer 2014 was to augment the efficiency of re-
ticipated in international or domestic response efforts. For sponse activities through incident management systems run
context, over the course of more than a decade, ≈300 CDC by national leaders and supported by an EOC reporting to
the president of each affected country. These systems were
Author affiliation: Centers for Disease Control and Prevention. developed in collaboration with WHO and served as the
Atlanta, Georgia, USA focal point for international assistance. CDC also helped
countries establish subnational EOCs in areas with Ebola
DOI: http://dx.doi.org/10.3201/eid2111.150949
Emerging Infectious Diseases • www.cdc.gov/eid • Vol. 21, No. 11, November 2015 1897
PERSPECTIVE
virus transmission in Liberia and Guinea; the United King- units (ETUs) and community care centers. Beginning in
dom similarly played a key role in Sierra Leone. When re- early October 2014, CDC designed and helped implement
sources had to be mobilized rapidly, the CDC Foundation, a strategy of rapid isolation and treatment of Ebola (RITE)
a not-for-profit philanthropic entity authorized by the US in Liberia. This strategy controlled outbreaks faster and
Congress in 1992 to help CDC improve its response capac- supported the care of patients in remote areas, cutting the
ity (10,11), supported staffing, logistics, data management, time to control outbreaks in half (Figure 1) and doubling
informatics, and operations of EOCs. survival rates (15).
Epidemiology and Surveillance Infection Control
Working with governments, nongovernmental organiza- In the 3 heavily affected countries, CDC and its partners
tions, and WHO, CDC epidemiologists assisted national- trained >25,000 health care workers in infection control,
and district-level staff in each country in identifying cases including use of personal protective equipment (PPE) (16).
and contacts and trained in-country staff to perform these A 3-day hands-on training course designed by CDC with
essential public health activities. Because clinical, public Médecins Sans Frontières trained >600 US health care pro-
health, laboratory, and data systems were overwhelmed viders on Ebola clinical care and infection control before
(12), CDC staff assisted with data entry and management, their deployment to West Africa (17).
including geographic information systems to track and
evaluate disease trends. Health Promotion and Communications
In addition to the efforts of partner organizations, CDC field
Contact Tracing teams included emergency risk communication specialists
After the cycle of exponential epidemic growth was broken to generate and disseminate accurate information, address
and personnel could refocus on contact identification, CDC rumors, decrease stigma, reduce unsafe burial practices,
strengthened work with national counterparts and WHO and respond to community needs. CDC staff in Liberia and
to help improve the quality of contact identification and Sierra Leone identified and promulgated burial practices
follow-up, including isolation of symptomatic contacts for that met community needs for culturally acceptable mourn-
clinical assessment and laboratory testing. These activities ing, thus reducing resistance to safe burials (18,19). In all
were vital to reduce Ebola transmission. WHO has played a countries, community engagement and effective communi-
critical role in improving contact tracing and contact man- cation were key strategies for successful outbreak control.
agement, particularly in Guinea (13).
Technical Guidance
Laboratory Testing CDC has issued >200 scientific documents, including >100
Global collaboration with laboratories from a European technical guidance documents, covering many aspects of
Union consortium made real-time quantitative reverse the response. CDC staff also worked closely with UNICEF
transcription PCR available in the heavily affected West and other partners to develop guidance in related areas,
Africa countries for patients and decedents suspected of such as safe reopening of schools (20).
having Ebola. CDC experts helped coordinate the labora-
tory section of the incident management system, supported Mobilization of Partners
laboratories in Liberia with the US Department of Defense During summer 2014, CDC recognized that despite Mé-
(DoD) and National Institutes of Health, and operated a decins Sans Frontières’ massive response; CDC’s own
field laboratory in Bo, Sierra Leone, that processed >2,000 response; and responses of affected countries, WHO, and
samples during a 3-week period at the height of the epi- international partners, the epidemic was spiraling out of
demic (14); by mid-2015, that laboratory had processed control. CDC then advocated to increase involvement by
>20,000 samples. the US government and the global community.
DoD, along with USAID/OFDA’s Disaster Assistance
Rapid Isolation and Treatment of Ebola Patients Response Team (DART), has been a key partner in this scale-
Rapid isolation and treatment of Ebola patients is a key up. Initially focused on researching treatments and vaccines
strategy to stop Ebola outbreaks. Each country had limited and providing laboratory diagnostics, in September 2014,
capacity to isolate and treat patients, and strategies to do DoD took the lead on constructing, supplying, and maintain-
so effectively and safely evolved over time. In collabora- ing a field hospital to treat health care workers with Ebola
tion with the US Agency for International Development’s in Liberia. DoD also deployed 3,000 military personnel for
Office of Foreign Disaster Assistance (USAID/OFDA), logistics and coordination, provision of medical personnel to
WHO, DoD, and multiple other partners, CDC provided train health care workers, establishment of additional treat-
technical support and training to establish Ebola treatment ment centers in Liberia, and operation of 3 mobile medical
1898 Emerging Infectious Diseases • www.cdc.gov/eid • Vol. 21, No. 11, November 2015
Ebola in West Africa—CDC’s Role
Figure 1. Decreased size and duration of outbreaks in remote areas before and after implementation of the Rapid Isolation and
Treatment of Ebola (RITE) strategy, Liberia, 2014. Size of circle is proportional to number of cases in cluster.
laboratories (21). The DART provided coordination to rap- treatment, and safe burials) had to be rapid, with action and
idly engage partners providing services and supporting re- progress measured in hours and days rather than in weeks
sponse efforts; CDC staff served as the technical lead for and months. In each country, CDC encouraged national
health, public health, and medical issues within the DART. leaders, incident managers, health workers, the media, and
communities to take action immediately, because even a
Epidemic Modeling rapid international response would not be fast enough.
A CDC model that projected the possible trajectory of the Third, the model identified a tipping point at which the
epidemic if the trend of rapid transmission through August epidemic would plateau and decline if enough (i.e., >70%)
2014 continued unabated was key to increasing the speed Ebola patients were isolated effectively and decedents bur-
and scale of the US and global response (22). The worst- ied safely. This finding led to establishment of community
case scenarios of the model made clear the need for urgent isolation facilities (24) and to contracting by USAID/OFDA
action and helped stimulate a massive global response. for burial teams that worked to technical specifications es-
Analysis from the model provided 4 key findings. tablished by CDC, first in Liberia and later in Sierra Leone
First, cases were increasing exponentially, and the response (25). In Liberia, experienced CDC public health specialists
needed was massive and urgent. CDC helped facilitate as- conducted detailed planning exercises with community,
sistance, including from the African Union, which mobi- political, medical, and public health leaders in each county
lized nearly 1,000 staff, including doctors, nurses, epide- to identify where sick persons could be isolated until ETUs
miologists, and health educators (23). were constructed and how contacts could be monitored and
Second, the model predicted a severe penalty for delay; cared for if they became ill.
case numbers at the peak roughly tripled for every month of Fourth, the model predicted that when the tipping
delayed scale-up (Figure 2). Thus, interventions (isolation, point was reached, transmission would decline rapidly.
Emerging Infectious Diseases • www.cdc.gov/eid • Vol. 21, No. 11, November 2015 1899
PERSPECTIVE
This prediction was shown to be accurate in the following
months in Liberia and Sierra Leone (Figure 3). For Libe-
ria, the model’s prediction that if urgent action were taken,
there would be 10,000–27,000 cumulative cases by January
21, 2015, closely matched the 8,500–24,000 cases that oc-
curred (Figure 4). The predictions also closely matched the
actual case trajectory after effective intervention.
Border Health Security
CDC worked with ministries of health and airport authori-
ties in all 3 heavily affected countries, as well as in other af-
fected countries, to establish screening of travelers leaving
the country by air to prevent sick or exposed persons from
boarding planes. By mid-2015, >200,000 travelers leaving Figure 2. Estimated impact of delaying intervention on daily
number of Ebola virus disease cases, Liberia, 2014–2015. The
Guinea, Liberia, and Sierra Leone had been screened. In
intervention modeled is as follows: starting on September 23,
addition to reducing the likelihood of additional spread of
2014 (day 181 in model), and for the next 30 days, the percentage
Ebola to other countries, this screening, along with CDC’s of all patients in Ebola treatment units increased from 10% to
work with airlines to address air transport industry and 13%. This percentage was again increased on October 23, 2014
flight crew concerns, helped enable humanitarian and pub- (day 211 in model) to 25%, on November 22, 2014 (day 241 in
model) to 40%, and finally on December 22, 2014 (day 271 in
lic health organizations to sustain travel to affected areas by
model) to 70%. Day 1 in model is March 3, 2014. The impact of a
regular commercial airline flights. CDC staff also provided
delay of starting the increase in interventions was then estimated
technical assistance on measures to reduce risk for spread by twice repeating the above scenario but setting the start day
through maritime ports and across land borders. on either October 23, 2014, or November 22, 2014. When the
intervention is started on November 22, 2014, the peak is not
reached by January 20, 2015, which is the last date included in
Innovation
the model. Graph based on Figure 10 in Meltzer et al. (22).
CDC laboratory scientists implemented high-throughput
laboratory capacity by using robotics and collaborated with
private industry to promote development of lateral-flow system oversaw training of 2,300 health care staff, creation
assays to detect Ebola in point-of-care settings within 30 of an ETU in 14 days, and identification of >800 contacts;
minutes after a finger stick or oral swab (6). In addition conducted 19,000 home visits of these contacts to moni-
to supporting the National Institutes of Health randomized tor symptoms and temperatures; and screened >150,000
controlled trials of Ebola treatment (27) and vaccines (28), persons at airports. Although 19 secondary cases of Ebola
CDC staff worked with Sierra Leone authorities to imple- occurred in 3 generations of spread in 2 cities, this rapid ac-
ment a parallel Sierra Leone Trial to Introduce a Vaccine tion controlled transmission, and Nigeria has been Ebola-
against Ebola (STRIVE), an adaptive, phased-introduction free since this incident (3).
trial of a vaccine candidate among health workers in that CDC staff provided similar assistance in Mali after a
country (8,9). child arriving from Guinea died of Ebola and again after
a cluster of cases occurred from a person from the Mali–
Support to Other At-Risk Countries Guinea border who had previously undiagnosed Ebola
In Nigeria, a cluster of Ebola cases in July 2014 resulted (29), and in Senegal after an incident of disease importa-
from a traveler from Liberia. CDC deployed disease control tion (4). CDC also collaborated with WHO to increase pre-
experts to Lagos, the country’s most populous city, within paredness in at-risk countries by helping establish EOCs,
72 hours and, in the first week after disease confirmation, surveillance for hemorrhagic fever and clusters of deaths,
supplemented response efforts with 13 Field Epidemiology training in contact tracing, laboratory specimen transport
Training Program (FETP) trainees, graduates, and trainers and testing, isolation capacity for patients suspected of
who had experience in epidemiology and infection control. having Ebola, health communication messages, and border
In the 2 weeks that followed, CDC sent additional agency health security.
staff and helped mobilize 40 CDC-trained physicians from
Nigeria’s FETP. With the Nigerian government and part- Ebola in the United States
ners, CDC facilitated creation of an effective incident man- Before diagnosis of the first case of Ebola imported to the
agement system, using leadership and staff from the Nige- United States, CDC alerted US health care providers to
rian Polio Eradication Program and support from the Bill consider Ebola if compatible signs and symptoms manifest-
and Melinda Gates Foundation. This incident management ed within 21 days after a traveler arrived from an affected
1900 Emerging Infectious Diseases • www.cdc.gov/eid • Vol. 21, No. 11, November 2015