Recent global health events like the Covid-19 pandemic, recurring Ebola outbreaks, tuberculosis, HIV, and the anticipated impact of climate change on health underscore the need to enhance public health capacity and allied sectors globally. Improved public health capacity helps in early detection of health events, preventing small events from becoming large-scale emergencies and helps to manage essential health services (1). Field epidemiology, a branch of Public Health, is crucial in understanding disease evolution and course and tracking its progress against control measures. The role of field epidemiologists was reinforced during the Covid-19 pandemic response.

The 73rd World Health Assembly recognized the importance of strengthening the public health workforce, especially epidemiologists, in response to the pandemic. The adoption of resolution 73.8.12 emphasized providing appropriate remuneration, resources, and training to health professionals, including under-represented cadres like epidemiologists. The Independent Panel for Pandemic Preparedness and Response also recommended investing in the frontline public health workforce to quickly detect and respond to emerging outbreaks (2). The Intergovernmental Negotiating Body, tasked with developing a pandemic treaty, highlighted the need to invest in the public health workforce, including epidemiology capacity. In December 2022, the INB recommended strengthening and sustaining an adequately skilled and committed health workforce, including at the frontline of pandemic prevention, preparedness, response, and recovery (1).

Despite the crucial role of epidemiologists, there is no International Labour Organization (ILO) classification or job definition for them in many national health systems. Field epidemiology training programs (FETPs) provide on-site training to enhance public health surveillance and response to health threats (3). These programs, structured at three levels—frontline (3 months), intermediate (9–12 months), and advanced (20–24 months) (4)have trained over 22,000 people across 80 countries by 2023 (5). Training is competency-based, combining practical service provision with theoretical courses, with mentors guiding trainees’ professional development.

FETPs have significantly contributed to responding to major public health threats like the COVID-19 pandemic. Although traditionally focused on infectious diseases, FETP graduates and trainees have also worked on non-communicable diseases and responses to natural disasters and humanitarian emergencies. Graduates are expected to assume positions within their national public health systems and leadership roles in ministries of health, NGOs, and international organizations. However, few studies have documented the nature and scope of FETP contributions to public health (6, 7). The main objective of this review is to describe the integration of FETP trainees and graduates into priority public health programs.

We conducted an electronic search using the Web of Science, PubMed, and Google databases. A combination of Medical Subject Heading (MeSH) terms, subject headings, keywords, and Boolean operators was used to cover concepts related to field epidemiology.

In PubMed, we used search terms like “Epidemiologist,” “Field Epidemiologist,” “Public health,” “Health workforce,” “Field epidemiology,” “Training program,” and “FETP.” These were used both together and separately in various combinations to ensure comprehensive coverage. We applied various combinations such: “Epidemiologist” AND “Field Epidemiologist,” “Public health” AND “Health workforce,” and “Field Epidemiologist” AND “Public health.” “Epidemiologist” AND “Health workforce” (public health OR health workforce) AND FETP training.

For the Web of Science, we used the same terms as in PubMed, with search strings such as: “FETP workforce” AND “Public health,” “Public health” AND “training,” and “Field Epidemiologist” AND “careers.”

Google was used to identify gray literature to fill gaps in the databases. Search terms included “public health, workforce,” combined with one of the following: “training, retention, careers, field epidemiologist.” We sought journal articles, review papers, research reports, and conference reports published in English between January 2012 and December 2021 with full text available, including journal articles, review papers, research reports, and conference proceedings, with available full text. We excluded articles not in English, those unrelated to the epidemiology workforce or FETP, and those without full-text access.

Duplicates were removed, and we screened titles and abstracts for relevance. If abstracts did not provide sufficient information for eligibility, we retrieved the full articles to make an informed decision on inclusion. The review focused on three thematic areas:

We developed a standardized data extraction form to capture study characteristics and thematic content relevant to the research questions. Data extracted included publication details (author, year, country/location), thematic focus, type of publication, and the reported engagement of FETP graduates and trainees within ministries of health or other public health organizations.

We conducted a descriptive analysis of publication geographic distribution. We then described the contributions and roles of FETP graduates based on their specific countries engagement within health ministries and other public health bodies. We described the engagement of FETP graduates and trainees in ministries of health and the main areas where they work. The method for selecting articles is presented in Figure 1.

The database search yielded 1,240 results (489 in PubMed, 742 in Web of Science), and a secondary search using Google added nine more results (Figure 1). After screening titles and abstracts based on the inclusion and exclusion criteria, 175 articles were selected for full-text examination. Finally, 30 articles were included in the review (Table 1). Of these, eight were from Africa, four from Southeast Asia, three from the Eastern Mediterranean, two each from Europe, the Western Pacific, and the Pan-American regions, while three focused on a global perspective and were not region-specific (Figure 2).

In this review, we use the term “trainee” to designate a person enrolled in an FETP and “graduate” for a trainee who has completed the program.

This study summarizes the involvement of FETP graduates and trainees in regional and national public health priorities and their career trajectories. The literature review highlights the significant global impact of FETPs in strengthening public health responses, particularly during the COVID-19 pandemic and other disasters. Across all six WHO regions, FETP trainees and graduates have been actively engaged in various aspects of the pandemic response, including surveillance, rapid response teams, case investigation, coordination, risk communication, and community engagement. These activities align with the core competencies that FETPs aim to achieve, demonstrating the effectiveness of these programs in preparing professionals for real-world public health challenges (13–15, 20, 22).

Our findings indicate that FETP alumni have engaged in various domains outlined in the Essential Public Health Functions for International Health Regulations implementation (6, 8, 18, 21, 32, 33). This positions FETPs at the forefront of developing a public health workforce capable of implementing IHR and other public health functions.

Ministries of Health partner with FETP programs and acknowledge the contributions of FETP graduates and trainees to public health systems. This is evidenced by the extensive engagement of FETPs at all levels, from national to district, the adoption of surveillance systems developed by graduates, the acceptance of FETP recommendations, and the promotion of graduates to leadership positions within ministries of health (3, 8, 19, 24). Nonetheless, some countries still feel the program lacks sufficient recognition.

The career trajectories of FETP graduates highlight the long-term impact of these programs on public health. Whether in government ministries, international organizations, NGOs, or academia, FETP alumni have assumed leadership roles and significantly contributed to public health policy, research, and practice. The retention of graduates within national health systems, as seen in Mozambique and South Africa, underscores the value placed on FETP-trained professionals and their ongoing contributions to public health. However, challenges remain in tracking alumni career paths to assess their long-term impact on health outcomes, which is crucial for informing program improvements and resource allocation.

This review contributes to the FETP Enterprise, a vast multi-partner effort in developing, implementing, and evaluating FETPs in over 100 countries. It highlights the contributions of FETP graduates and fellows across all public health domains, advocating for enhanced field epidemiology capacity globally. Additionally, the University of Newcastle, Australia, is conducting operational research on the health impact and economic value of PH activities involving FETP graduates (surveillance, outbreak investigations, interruption of transmission chains) (34). This work is essential for advocating for more efficient government investments in FETPs.

WHO is leading efforts to develop a Roadmap for the Public Health and Emergency Workforce, aiming to map workforce capability in 20–30 countries over the coming years. This initiative seeks to better define and classify key public health roles, ensuring a professional public health workforce with a clear career structure to attract and retain well-trained staff.

WHO has recently established a unit for Field Epidemiology Capacity Strengthening with the objective of initiating efforts in Regional and Country Offices towards supporting FETPs or field epidemiology capacity strengthening programs. The new unit will lead in developing a global roadmap that ensures the pressing need to establish field epidemiology as a fundamental component of the public health workforce. Together with global and regional associations of FETPs, the skills and competencies of FETP need to be defined and standardized and incorporated within a new occupation classification with ILO, as part of the roadmap. Further efforts in this area should collect example job descriptions in order to create a repository of the roles that FETP graduates can play to ensure essential public health functions. National Governments, National Public Health Institutes, and Public Health Schools and Training Institutions need to collaborate to develop epidemiology as a career with a clear professional structure. Some literature suggests the need for the establishment and implementation of strategies that will ensure the retention of FETP graduates by appropriately placing them where their skills are needed, and providing them with remuneration incentives (3).

While current FETPs in most countries have been constructed upon the model of the Epidemic Intelligence Service of the US CDC, more curricula are being developed to reinforce field epidemiology workforce health emergency responses. This will complement the existing national FETPs and extend the number of field epidemiologists in countries and for international deployments. As we need to equip the future field epidemiologist with the skills and competencies to face the health challenges that lie ahead, applying the One Health approach to face challenges like zoonosis, vector-borne diseases, climate change, and others is an important next step. Competencies in One Health field epidemiology should be added to current FETP curricula as they are relevant to the response to complex emergencies, humanitarian health, migrants’ health, famine, drought, and other climate change related threats.

Some limitations are inherent to the methodology applied: results of literature search are dependent on the acceptance of the manuscripts by scientific journals. Negative results, such as a poor retention rate of FETPs or the poor performance of FETP graduates in an outbreak investigation, are less likely to be published. Also, we noted that authors of most of the studies reported in this review are affiliated to institutions that are supporting FETPs across the world, either through funding, developing training materials or mentoring the FETP trainees. At the same time, we can see that all papers systematically describe success stories, which tend to prove that in some instances there might be a need to convince others of the success of the work done. This might be seen as a bias derived from a conflict of interest not always reported in the articles.

A thorough examination of the challenges FETP graduates encounter when implementing public health interventions was hindered by limited data availability. Certain regions may experience distinct obstacles to integrating FETP graduates into their national health systems. However, the data collected lacked the regional specificity needed to fully explore these unique barriers. Thus, further studies are recommended to investigate this issue in greater depth.

While FETP graduates’ contributions to capacity building and response activities were well-documented in the reviewed literature in this study, direct measurements of health outcomes—such as reduced outbreak frequency or improved response efficiency—were rarely reported. This gap in outcome-based evaluations underscores the need for future research to quantify the public health impact of FETP graduates and provide a stronger evidence base for assessing program effectiveness.

FETPs have emerged as indispensable tools for strengthening public health systems, enhancing epidemic preparedness and response, and building a cadre of skilled professionals capable of addressing evolving health challenges. The evidence presented in this literature review highlights the importance of continued investment in FETPs and the need for ongoing research and evaluation of the FETP programs to maximize their impact on global health security. The review shows that the engagement of FETP trainees and graduates encompasses the traditional epidemiology domain of surveillance and outbreak investigation and is now extending to other public health issues such as non-communicable diseases, climate change, and road accidents. FETPs around the world shall be better supported and included into the Public Health systems of their countries if they are recognized and their occupation is defined in the ILO classification.