Secondary Logo

Journal Logo

Research Reports

Enhancing Epidemiology Capacity During the 2014-15 West Africa Ebola Outbreak: An Assessment of the Role of Applied Public Health Epidemiologists

Perrotta, Dennis M. PhD; Lemmings, Jennifer MPH; Maillard, Jean-Marie MD, MSc

Author Information
Journal of Public Health Management and Practice: November/December 2020 - Volume 26 - Issue 6 - p 595-601
doi: 10.1097/PHH.0000000000000982
  • Open


This article describes the deployment and contributions of applied public health professionals with epidemiology expertise (epidemiologists) in the response to a major international public health emergency, the 2014-2015 West African outbreak of Ebola virus disease (EVD). By April 13, 2016, the virus was linked to 28 652 total cases reported (suspected, probable, or confirmed), 15 261 laboratory-confirmed cases, and 11 325 deaths, making this the largest EVD outbreak in history.1 Although many circumstances contributed to the severity of the outbreak, 1 key factor was the highly limited capacity for public health surveillance and response in the countries most adversely affected.2

In late 2014, the Centers for Disease Control and Prevention (CDC) requested the support of a partner organization able to provide French-speaking epidemiologists to enhance epidemiologic capacity in countries already impacted by EVD or threatened by the virus, owing to close geographic proximity to outbreak areas. The Council of State and Territorial Epidemiologists (CSTE) agreed to be that partner.

About CSTE

The CSTE is the professional association representing public health epidemiologists working at state, local, and territorial public health agencies. The association supports the development of practicing epidemiologists; provides technical advice and assistance to partners, including CDC; and supports effective public health surveillance and good epidemiologic practice through training, capacity development, and peer consultation.

The CSTE members have expertise in a broad range of subject areas, as evidenced by the association's 6 steering committees and 30 subcommittees, which address everything from chronic disease to climate change. Of direct relevance to infectious disease emergencies are CSTE committees focused on border and international health, epidemiology methods, surveillance practice and implementation, workforce development, maternal and child health, public health law, public health emergency preparedness, disaster epidemiology, occupational health surveillance, and disease-specific subcommittees. Thus, CSTE has access to professionals who can apply their expertise in the field, at home or abroad, and offer surge capacity to the national or international agencies charged with emergency response.


Recruitment and deployment

Beginning in late 2014, the CSTE recruited epidemiologists and other public health professionals (described as epidemiologists in this article) to provide technical assistance and guidance to the ministries of health in Guinea, Sierra Leone, and Liberia—the 3 countries at the center of the outbreak—as well as Cote d'Ivoire, Mali, Senegal, and Benin—the neighboring nations deemed most at risk for imported cases from outbreak-affected areas.

Solicitations for professionals interested in international outbreak response were sent to CSTE members, posted on the CSTE Web site, and disseminated through state epidemiologists. Interested individuals were not required to be CSTE members or epidemiologists but were required to have relevant public health experience. Preferred applicants were able to deploy for at least 30 days, had no disqualifying health conditions, and had demonstrated expertise in epidemiology, data management, infection control, incident command system management, outbreak response, health communications, and/or laboratory practice. Although the CSTE initially recruited individuals proficient in French or Portuguese, it also reviewed applications from public health professionals proficient in other languages.

The CSTE then developed an international consultation database, listing individuals' skills, current job, and past international experience, and shared this information (plus each applicant's resume or curriculum vita) with the CDC. The CDC, in turn, worked with in-country representatives to match professionals with a particular job function in a particular country during a specific time interval. Prior to deployment, accepted individuals attended a CDC training program in Atlanta, Georgia.

The epidemiologists selected for deployment were able to provide

  • capacity building, technical assistance, and guidance to in-country ministries of health and
  • assessment of existing capabilities and recommendations to improve public health policies and procedures relevant to the outbreak response.

The recruited professionals were deployed to West Africa between January 2015 and early 2017. Epidemiologists were deployed by the CSTE on behalf of the CDC. The first countries of deployment were Cote d'Ivoire, Mali, Senegal, and Benin where professionals were directed to work on preparedness in nonaffected countries, collaborating with the CDC field staff if any, and with other in-country US personnel. Those who later deployed to Guinea, Liberia, and Sierra Leone worked as part of CDC outbreak response field teams. Overall, from January 2015 through April 2017, the CSTE deployed 36 epidemiologists to Africa—including 8 who were deployed for multiple tours—and these professionals were on site for a total of 1185 days. Altogether, there were 45 deployments, and the average deployment period was 42 days (range: 18-94 days). Deployed professionals were compensated for their work.


A committee comprised of 3 CSTE epidemiologists who deployed to West Africa, a CSTE staff member, and a paid consulting public health professional developed an assessment tool to assess CSTE's contributions to local epidemiology surge capacity during the EVD outbreak and to characterize operational details that may inform future deployments. The tool was pilot tested by these 3 epidemiologists who deployed to Africa and adapted for online accessibility. Each of the 36 deployed epidemiologists received a link to the electronic assessment tool via e-mail, with instructions for log-in and completion. Nonresponders were contacted via e-mail and phone. Responses were collected and further collated using Qualtrics software (Provo, Utah). Responses were tabulated using Microsoft Excel software (Microsoft; Seattle, Washington). The assessment was not submitted for institutional review board exemption. Information was collected to support the receipt of funding received by the CDC and reflects valuable experiences for future applications during international public health emergencies.


Responses were received from 33 of the deployed epidemiologists, representing a 92% response rate.

Characteristics of deployed epidemiologists

Of 30 respondents, the home workplaces for the deployed professionals were reported as state health departments (n = 15, 50%), local health agencies (n = 7, 23%), academic institutions (n = 3, 10%), and independent consulting practices (n = 5, 17%). Concerning their work titles, 18 (60%) were employed as epidemiologists (state epidemiologist, infectious diseases epidemiologist, and senior epidemiologist), 8 (27%) as academicians or consultants, and 4 (13%) as other public health professionals (assistant health commissioner, health promotion specialist, and program specialist). Based on 25 responses, the respondents reported an average of 13.5 years of public health agency experience, with a range of 2 to 45 years. In this cohort of deployed epidemiologists, 18 (54.6%) spoke French fluently, and all 18 reported that their French language skills were required for their in-country job activities.

Predeployment training

All but 1 of the respondents participated in predeployment training at the CDC, with the average training period lasting 4.5 days. Most respondents reported attending more than 1 training session, with training topics ranging from Ebola basics to cultural sensitivity (Table 1). The majority (71%) reported that they found the training useful; 19% indicated the training was unhelpful, and 10% were unsure. Respondents indicated the following reasons as to why the training was not helpful (it was not a training, just informal meetings; content did not include actual work being done in-country; briefing did not include response, Ebola, or potential assignment; and training should include conversational French, specifically about the work using that vocabulary). Of note, training content and security requirements evolved over the outbreak as over time information changed.

TABLE 1 - Predeployment Training Received by Consulting Epidemiologists
Training Topic Number Participants (n = 32)
Ebola basics 26
Safety/security 22
Infectious disease surveillance and response 15
Cultural sensitivity 14
Laboratory safety 2

Deployment countries, activities, and contributions

Collectively, respondents made 40 deployments to 7 countries, were deployed for an average of 42.0 days, and worked an average of 10.4 hours per day, contributing an estimated 17 456 hours to the response effort (calculated by multiplying 1678.5 total days of deployment by 10.4 h/d). Altogether, 19 (47%) consulting epidemiologists were deployed to Guinea, 8 (20%) to Liberia, 8 (20%) to Sierra Leone, 1 to both Guinea and Liberia (2.5%), and 1 each to Cote d'Ivoire, Mali, Benin, and Senegal.

Of the 33 respondents, 22 (67%) worked as epidemiologists (field, senior, or medical) during their Africa deployments, 8 (24%) as data team members, 2 (6%) as laboratory specialists (advisor, director), and 1 (3%) as a health communicator. Table 2 shows the percentage of their work in functional categories, with surveillance data management/informatics being the most time-intensive activity (comprising an average of 18.9% of respondents' in-country work hours), followed by infectious disease surveillance and response (17.7%), educating the general public and EVD survivors (13.0%), and surveillance field activities (12.8%).

TABLE 2 - Reported Field Work Activities
Field Activity Average Portion of Work Time (n = 33)
Direct outbreak field response, including case/control interviews 12.1%
Surveillance field activities 12.8%
Surveillance data management/informatics 18.9%
Providing training to in-country health care professionals 10.8%
Providing education/awareness to general public/survivors 13.0%
Resource coordination/logistical support 5.3%
Rapid diagnostic test/other clinical laboratory activity 7.2%
Other activities: General infectious disease surveillance and response 17.7%
Other activities: Planning, management, assessments 2.2%

The chief reported functional contributions made during deployments include improving surveillance processes (reported by 73.3% of respondents), building meaningful relationships to facilitate response activities (66.7%), improving data quality (53.3%), and additionally, improving understanding of the disease/outbreak (40.0%) (Table 3).

TABLE 3 - Contributions Made During Deployments (Multiple Responses Allowed)
Contribution Percent Reported (n = 33)
Improved surveillance processes 73.3
Built meaningful relationships for response 66.7
Improved data quality 53.3
Improved understanding of the disease/outbreak 40.0
Improved local health/medical response capacity 33.3
Other: Planning, coordination, mentoring 20.0

According to respondents, their in-country work added considerable value to Ebola-affected countries. The following are 3 representative responses to an open-ended question addressing “value added”:

“...working in providing epidemiologists, planning and logistical support for the measles outbreak, while maintaining Ebola surveillance, was very important.”

“...reignited my passion for public service. Field staff really make a difference in global outbreaks such as Ebola virus disease.”

“...strengthening of Ebola virus disease surveillance in phase 3 of the epidemic [which began in August 2015, with the goal of disrupting remaining chains of transmission and responding to any consequences of remaining Ebola risks3].”

Deployment challenges and professional benefits

Common deployment challenges range from high staff turnover (reported by 62.1% of respondents) to unclear roles or responsibilities (58.6%) to lack of local institutional knowledge (51.7%) (Table 4). Among the professional benefits of deployment to West Africa to assist with EVD outbreak response are stimulating enthusiasm for public health work (93.3%, n = 30), broadened perspective of global health (86.7%), and sharpened epidemiological skills (56.7%) (Table 5).

TABLE 4 - Deployment Challenges (Multiple Responses Allowed)
Challenges Reported Percent Reported (n = 29)
Constantly changing staff 62.1
Unclear roles or responsibilities 58.6
Lack of institutional knowledge/memory 51.7
No clear supervisor 34.5
Mastering complexities of local response within duration of deployment 31.0
Communication issues, including language 24.2
Other: Responsibilities too broad, coordination inadequate 20.7
Lack of transparency 13.8
Financial/logistic arrangements with employer 10.3
Personal illness while deployed 6.9
Security issues, including measures to reduce chances of terrorist attack 3.5

TABLE 5 - Professional Benefits From Deployments (Multiple Responses Allowed)
Benefit Provided From Deployment Percent Reported (n = 30)
Sharpened my epidemiology skills 56.7
Broadened my perspective of global health 86.7
Stimulated my enthusiasm for public health work 93.3
Other (increased communication skills, provided material for teaching MPH outbreak classes) 23.3
Deployment did not benefit me as a professional epidemiologist 0.0
Abbreviation: MPH, masters in public health.

Role of nonprofit public health organizations in international emergencies

According to respondents, nonprofit public health organizations, such as CSTE, can play important roles during international public health emergencies, including boosting international surge capacity (34.5%, n = 29), enhancing local response capacity (27.6%), advising in public health practice (13.8%), and “all of the above” (24.1%).


The 2014-2015 EVD outbreak generated one of the largest coordinated global public health responses in recent decades.4,5 In contrast to the smaller, mostly self-limited outbreaks seen since 1976 in the central region of Africa, the 2014-15 EVD outbreak affected countries in another part of the continent and, importantly, spilled into urban areas with devastating consequences.6 National and nongovernmental organizations already present in the affected countries initiated a local public health response, but the mobility of the population resulted in some of the exposed individuals traveling to larger communities and urban areas either during their incubation period or in search of care after becoming ill.5

Local medical capacity was already quite limited before the outbreak, with, for example, less than 1 physician per 10 000 population in Guinea, in Liberia, and in Sierra Leone—among the lowest physician densities in the world.7 Nonetheless, a local response was initiated and eventually supplemented with resources from the World Health Organization and governmental and nonprofit organizations from many countries.8 In particular, from July 2014 to March 2016, the CDC mounted its largest and longest outbreak response to date, employing more than 4000 agency staff, with nearly 2000 deployed off-site in international and US locations.9 As extensive as the CDC response was, the CSTE was critical in being able to identify and support additional public health epidemiologists to provide surge capacity during this response.

The CSTE has a long history of providing technical assistance and workforce training through epidemiologic consultations, assessments and on-site, local training sessions focused on timely topics, such as influenza surveillance. The EVD outbreak response in West Africa led to the association's first provision of direct, hands-on support in a real-time field response, with CSTE members conducting surveillance, contact tracing, and rapid diagnostic test evaluation, among other activities. The CDC initially asked the CSTE to provide senior epidemiologist volunteers able to speak French and to deploy for at least a month. With a membership of more than 1800, the CSTE rapidly identified a pool of volunteers meeting the selection criteria, including necessary language skills. In fact, some of the volunteers had been involved in EVD surveillance and response planning in their own states, in case of EVD importation by travelers or health care professionals returning from the region.

Predeployment training and orientation at CDC headquarters in Atlanta provided volunteers with an update on clinical and epidemiologic aspects of EVD, the current status of outbreak and response protocols implemented in the field, CDC operations, expected coordination and support from CDC headquarters, and federal predeployment requirements, such as security training. While virtually all senior state-level epidemiologists are familiar with incident command systems for large public health responses, their training typically does not extend to other topics covered in the predeployment training, such as operating in an environment of social unrest and terrorism threats. Similarly, cultural sensitivity training—taken by about a third of the volunteers—turned out to be especially important in a region where local beliefs, cultural norms, and resistance to outside intervention could be challenging.10

The first group of CSTE volunteers deployed to 4 francophone countries in the region at high risk for EVD importation. Subsequently, others were sent to the 3 countries at the epicenter of the crisis, with Guinea being the most frequent destination. Most volunteer assignments (73%) related to disease surveillance, training, and data management—areas of expertise for most CSTE-member, senior epidemiologists. Consequently, respondents' self-reported contributions closely match these assigned activities. Volunteers' senior level of public health experience also enabled other contributions, particularly “improved data quality,” and data analysis leading to “improved understanding of the disease and outbreak.” It is worth noting that volunteers' relatively long deployments also facilitated mentoring relationships with less experienced field staff—a benefit to the local public health workforce.

Deployment challenges included the social disruption and collapse of economic activity and public health services in Guinea, Liberia, and Sierra Leone—3 nations that were highly resource-constrained and chronically medically underserved even before the EVD outbreak. Tragically, the preexisting shortage of health care professionals was magnified by the outbreak, with at least 881 EVD cases, including 513 deaths, reported among health care workers in those 3 countries.11

Constant staff turnover, especially among the international responders, was another major challenge, cited by 62% of assessment respondents. And, for most, the problems stemming from high turnover were compounded by an ill-defined chain of command and ill-defined roles and responsibilities (from respondents' viewpoint). This nebulous situation can be seen as the result of a protracted epidemic on a fragile terrain of underserved health needs, where most foreign health care workers and other volunteers served only 4 to 6 weeks before returning home (the average deployment for epidemiologists deployed by CSTE was 42 days). The high turnover also impacted the continuity or response activities, with half of respondents citing difficulties with institutional knowledge or memory. For example, successive predecessors may have attempted various data management solutions, resulting in fragmented data sets rather than standardized databases. This suggests that a focused effort early in the outbreak response to develop standardized data collection tools could enhance efficiency. High turnover and length of stay across the response were a critical issue for this and can be expected for future responses. Longer deployments are not only a burden personally, professionally epidemiologists needed to take paid or unpaid leave from their jobs (or be retired) to deploy. Most assessment respondents (83%) were government employees whose managers understood that participating in the EVD response in West Africa could contribute to disease prevention locally. This acknowledgement is critical in being able to identify qualified individuals who are willing to deploy during public health emergencies.

Fortunately, personal illness was reported by few volunteers, and the highly visible and ubiquitous security measures, while new to most, were not perceived as a challenge.

Ultimately, the call from CSTE to serve in a global public health response provided the volunteers an opportunity to expand the scope of their professional practice beyond national, state, or local epidemiologic activities. Almost all respondents expressed satisfaction with their experience, and some reported that it was professionally stimulating and enhanced their understanding of global health. None expressed regrets.

The CSTE's experience in Africa is not unique; other public health associations have undertaken similar efforts to respond to international emergencies. For example, the Association of Public Health Laboratories—the professional association representing US state and local governmental health laboratories–deployed a consulting laboratory expert to Sierra Leone during the Ebola outbreak. That expert, a native of the region, helped draft the first version of the Ebola Response Laboratory Operational Manual; documented the capabilities and testing capacity of all in-country laboratories (most mobile laboratories operated by other international responders); and assisted with the launch of an Ebola proficiency testing program, among other things.12

Conclusion: Role of Nonprofit Organizations in Emergencies

The 2014-2016 EVD outbreak in West Africa demonstrates the value of tapping nonprofit public health associations, like CSTE, to access the expertise of their members for surge capacity in a situation requiring a sustained, months-long emergency response. In this case, the CSTE members contributed nearly 17 500 hours of applied public health epidemiology expertise. This experience was a first for CSTE, and this assessment confirms its success for the organization, as well as individual responders who reported making significant public health contributions during their Africa deployments. Information gathered from this assessment may provide a view into operational details that inform future emergency response deployments.

Although this sort of humanitarian and public health emergency had not been seen in modern times, it is not difficult to envision the emergence or reemergence of novel pathogens in resource-limited areas giving rise to a similar set of exceptional circumstances with similarly devastating consequences. Should this occur, lessons learned during the EVD outbreak serve as a starting point for improved public health response. In fact, since the response characterized in this report, there have been additional deployments to support recovery and capacity building. Nonprofit organizations such as CSTE stand ready to join the response.

Implications for Policy & Practice

  • Response to public health emergencies often requires sustained engagement of expertise, which may not be present. There are nongovernmental organizations that can, with minimal policies and procedures, be useful in boosting surge capacity and result in an improved response.
  • Deployments and cross-deployment activities during international public health emergencies provide beneficial experiences to state and local public health epidemiology professionals.
  • Improving public health epidemiology capacity internationally during global response efforts can reduce the likelihood or slow down the spread of pandemic diseases.


1. Centers for Disease Control and Prevention. Ebola (Ebola virus disease). 2014-2016 Ebola outbreak in West Africa. Accessed February 26, 2018. Published December 27, 2017.
2. Shoman H, Karafillakis E, Rawaf S. The link between the West African Ebola outbreak and health systems in Guinea, Liberia and Sierra Leone: a systematic review. Global Health. 2017;13:1.
3. World Health Organization. Ebola response phase 3: framework for achieving and sustaining a resilient zero. Published September 2015. Accessed March 5, 2018.
4. The WHO Ebola Response Team. After Ebola in West Africa, unpredictable risks, preventable epidemics. N Engl J Med. 2016;375:587–596.
5. Spengler JR, Ervin E, Towner JS, Rollin PE, Nichol ST. Perspectives on West Africa Ebola virus disease outbreak, 2013-2016. Emerg Infect Dis. 2016;22(6):956–963.
6. Bell BP, Damon IK, Jernigan DB, et al. Overview, control strategies, and lessons learned in the CDC response to the 2014-2016 Ebola epidemic. MMWR Suppl. 2016;65(suppl 3):4–11.
7. World Health Organization. Global Health Observatory data repository. Updated April 5, 2018. Accessed February 6, 2019.
8. National Academies of Sciences, Engineering, and Medicine; Health and Medicine Division; Board on Global Health; Forum on Microbial Threats. The Ebola Epidemic in West Africa: Proceedings of a Workshop. Washington, DC: National Academies Press. Global Preparedness and Response Efforts. Published November 30, 2016. Accessed February 28, 2018.
9. Frieden TR. Foreword. MMWR Suppl. 2016;65(suppl 3):1–3.
10. Bedrosian SR, Young CE, Smith LA, et al. Lessons of risk communication and health promotion—West Africa and United States. MMWR Suppl. 2016;65(suppl 3):68–74.
11. World Health Organization. Ebola situation report. Published November 4, 2015. Accessed February 28, 2018.
12. Maddox N. Leveraging laboratories to halt Ebola. Lab Matters. 2015;1:9–13.

epidemiologists; global emergency response; NGO

© 2019 The Authors. Published by Wolters Kluwer Health, Inc.