Abstract

Introduction

The Dictionary of Epidemiology, edited by the International Epidemiologic Association, proposes the following definition for Epidemiology: “The study of the occurrence and distribution of health-related events, states, and processes in specified populations, including the study of the determinants that influence such processes, and the application of this knowledge to control health problems”¹1 Porta M. A dictionary of epidemiology. 6a ed. New York: Oxford University Press; 2014.. It is a useful definition in lexicographic and operational terms, as it is provided by a dictionary committed to recognizing the plurality of practices and perspectives in Epidemiology¹1 Porta M. A dictionary of epidemiology. 6a ed. New York: Oxford University Press; 2014.. However, and consequently, such diversity encompasses varied meanings of Epidemiology, and reflects, to some extent, theories, methods, values, and social commitments existing in different historical and geographical contexts²2 Breilh J. Critical epidemiology and the people’s health. New York: Oxford University Press; 2021..

More than relevant and necessary definitions, it is important to delimit epidemiological theories that provide subsidies to think about and seek explanations in the sphere of its specific domain of interest, namely the population distribution of diseases, disabilities, deaths, health and their determinants and restraints, in space and time³3 Krieger N. Commentary: society, biology, and the logic of social epidemiology. Int J Epidemiol. 2001; 30(1):44-6.^,44 Krieger N. Epidemiology and the people’s health: theory and context. New York: Oxford University Press; 2011.. Epidemiological theories of health events distribution need to address not only the mechanisms causing the events per se (for example, diseases), but also the reasons that lead to spatial-temporal heterogeneities in the distribution of these events and their determinants⁴4 Krieger N. Epidemiology and the people’s health: theory and context. New York: Oxford University Press; 2011..

If it were only a scientific enterprise, perhaps this theoretical delimitation would be sufficient for epidemiology to accomplish its mission. However, the objectives of Epidemiology go much further to include generation of knowledge that can be translated and applied to bring about changes that improve populations’ health and quality of life, and reduce social inequalities in health⁴4 Krieger N. Epidemiology and the people’s health: theory and context. New York: Oxford University Press; 2011.^,55 Krieger N. Epidemiology and the web of causation: has anyone seen the spider? Soc Sci Med. 1994; 39(7):887-903.. Such commitment is inherent in Epidemiology, as different authors and organizations recognize, but it is not necessarily a consensus among epidemiologists. Some understand that Epidemiology should harbor the freedom of searching for decontextualized knowledge (for example, knowledge that focuses on the understanding of illness mechanisms in individuals), as it might bring more immediate health benefits when compared to social changes, which are complex and hard to achieve⁶6 Rothman KJ, Adami HO, Trichopoulos D. Should the mission of epidemiology include the eradication of poverty? Lancet. 1998; 352(9130):810-3.. In general terms, this view, broadly dominant during many years, corresponds to the so-called Modern Epidemiology, also referred to by its critics as “risk factor epidemiology”, whose analytical focus went down from population to the individual and emphasized methods and techniques to the detriment of theory⁷7 Pearce N. Traditional epidemiology, modern epidemiology, and public health. Am J Public Health. 1996; 86(5):678-83.^,88 Keyes K, Galea S. What matters most: quantifying an epidemiology of consequence. Ann Epidemiol. 2015; 25(5):305-11..

The authors who adopt this point of view recognize that epidemiological research is included in the context of Public Health, and must be motivated by its potential for producing and maximizing benefits to the population’s health⁹9 Poole C, Rothman KJ. Epidemiologic science and public health policy. J Clin Epidemiol. 1990; 43(11):1270-1.^,1010 Savitz DA, Poole C, Miller WC. Reassessing the role of epidemiology in public health. Am J Public Health. 1999; 89(8):1158-61.. However, they also understand that the epidemiologist should carry out their scientific activity with rigor and objectivity, without passion, leaving the roles of advocacy and implementation to policy makers⁹9 Poole C, Rothman KJ. Epidemiologic science and public health policy. J Clin Epidemiol. 1990; 43(11):1270-1.^,1010 Savitz DA, Poole C, Miller WC. Reassessing the role of epidemiology in public health. Am J Public Health. 1999; 89(8):1158-61.. Undoubtedly, although decisions about incorporation and implementation of health actions, technologies, programs, and policies must be guided by the best scientific evidence available, they cannot and must not be grounded on epidemiological evidence only, nor should epidemiologists alone be responsible for this task. However, viewing Epidemiology as an activity whose nature is eminently scientific implies a specific, naive, disinterested and idyllic conception of Science devoid of moral values and political interests¹¹11 Krieger N. Questioning epidemiology: objectivity, advocacy, and socially responsible science. Am J Public Health. 1999; 89(8):1151-3.. Epidemiology, just like Science, is a human enterprise that cannot argue for neutrality, mainly in a context of growing influence of industries and corporations in epidemiological research¹²12 Wing S. Whose epidemiology, whose health? Int J Health Serv. 1998; 28(2):241-52.

13 Breilh J, Jefer CB, Castelman BI, Cherniack M, Christiani DC, Cicolella A, et al. Texaco and its consultants. Int J Occup Environ Health. 2005; 11(2):217-20.

14 Pearce N. Commentary: the rise and rise of corporate epidemiology and the narrowing of epidemiology’s vision. Int J Epidemiol. 2007; 36(4):713-7.^-1515 Legg T, Hatchard J, Gilmore AB. The science for profit model-how and why corporations influence science and the use of science in policy and practice. PLoS One. 2021; 16(6):e0253272..

The implications of divergent views on the domain and objectives of Epidemiology for its theoretical, conceptual, and practical configuration, and for its relations to Collective Health itself and other fields of knowledge, have been broadly discussed in many countries and also in the Brazilian context²2 Breilh J. Critical epidemiology and the people’s health. New York: Oxford University Press; 2021.^,44 Krieger N. Epidemiology and the people’s health: theory and context. New York: Oxford University Press; 2011.^,77 Pearce N. Traditional epidemiology, modern epidemiology, and public health. Am J Public Health. 1996; 86(5):678-83.^,88 Keyes K, Galea S. What matters most: quantifying an epidemiology of consequence. Ann Epidemiol. 2015; 25(5):305-11.^,1616 Barreto ML. Por uma epidemiologia da saúde coletiva. Rev Bras Epidemiol. 1998; 1(2):104-22.

17 Susser M. Does risk factor epidemiology put epidemiology at risk? Peering into the future. J Epidemiol Community Health. 1998; 52(10):608-11.^-1818 Camargo KR Jr, Ortega F, Coeli CM. Modern epidemiology and its discontents. Rev Saude Publica. 2013; 47(5):984-91.. Thus, I do not aim to revisit this debate from a theoretical-conceptual point of view. My objective is to use my personal experience of the greatest health crisis of our generation, the Covid-19 pandemic, to present reflections on some of the challenges faced by Epidemiology (and by epidemiologists) in this context, and to identify themes and questions that deserve to be debated thoroughly, so that they can be developed in the next years.

Epidemiology in the spotlight

The Covid-19 pandemic is one of the most impactful events in the recent history of Public Health. It has been called “mass disabling event” or “mass deterioration event”¹⁹19 Lowenstein F, Davis H. Long Covid is not rare. It’s a health crisis [Internet]. New York: The New York Times; 2021 [citado 19 Jun 2022]. Disponível em: https://www.nytimes.com/2021/03/17/opinion/long-covid.html
https://www.nytimes.com/2021/03/17/opini... ^,2020 Mazer B. Long Covid could be a ‘mass deterioration event’ [Internet]. Washington: The Atlantic; 2022 [citado 19 Jun 2022]. Disponível em: https://www.theatlantic.com/health/archive/2022/06/long-covid-chronic-illness-disability/661285/
https://www.theatlantic.com/health/archi... . Such designations emphasize not only direct short-, medium- and long-term effects on those who developed the disease and their implications to health policy and planning, but also highly disruptive indirect effects on population health. For example, the Covid-19 pandemic has affected the offer of preventive programs, like vaccination and cancer screening, as well as the delivery of continuous care for chronic conditions²¹21 Alves JG, Figueiroa JN, Urquia ML. Impact of Covid-19 on immunization of Brazilian infants. Int J Infect Dis. 2021; 107:252-3.

22 Horta BL, Silveira MF, Barros AJD, Hartwig FP, Dias MS, Menezes AMB, et al. Covid-19 and outpatient care: a nationwide household survey. Cad Saude Publica. 2022; 38(4):e00194121.^-2323 Ribeiro CM, Correa FM, Migowski A. Short-term effects of the Covid-19 pandemic on cancer screening, diagnosis and treatment procedures in Brazil: a descriptive study, 2019-2020. Epidemiol Serv Saude. 2022; 31(1):e2021405..

The Covid-19 pandemic caught the Brazilian population in a situation of profound social, economic, and program vulnerability²⁴24 Werneck GL. The Covid-19 pandemic: challenges in assessing the impact of complex and multidimensional problems on the health of populations. Cad Saude Publica. 2022; 38(4):PT045322.. Thus, a perfect storm was formed, grounded on the dismantling of social policies, on the chronic underfunding of the Brazilian National Health System (SUS), and on the catastrophic management of the pandemic²⁵25 Werneck GL, Carvalho MS. A pandemia de Covid-19 no Brasil: crônica de uma crise sanitária anunciada. Cad Saude Publica. 2020; 36(5):e00068820.^,2626 Werneck GL. Long-term mass population effects of the Covid-19 pandemic: a long way to go. Cad Saude Publica. 2022; 38(7):e00115222.. Pandemics are phenomena with biological, ecological, social, and historical dimensions. As such, they unveil and deepen social inequalities, causing the greatest burden of illness and death from Covid-19 to fall on the most vulnerable²⁷27 Oliveira RG, Cunha AP, Gadelha AGS, Carpio CG, Oliveira RB, Corrêa RM. Racial inequalities and death on the horizon: Covid-19 and structural racism. Cad Saude Publica. 2020; 36(9):e00150120.^,2828 Nassif-Pires L, Carvalho L, Rawet E. Public Policy Brief, No. 153. Multidimensional Inequality and Covid-19 in Brazil. Blithewood: Levy Economics Institute of Bard College; 2020.. This dramatic picture can be better expressed as a syndemic, in which the Covid-19 pandemic interacts with different sources of health, social, and environmental vulnerabilities, and intensifies the adverse effects of all factors on the population’s health²⁶26 Werneck GL. Long-term mass population effects of the Covid-19 pandemic: a long way to go. Cad Saude Publica. 2022; 38(7):e00115222.^,2929 Singer M, Bulled N, Ostrach B, Mendenhall E. Syndemics and the biosocial conception of health. Lancet. 2017; 389(10072):941-50..

The health crisis immediately threw Epidemiology into the heart of the storm. Although the key principles to face health crises necessarily demand interdisciplinary and intersectoral perspectives³⁰30 The Academy of Medical Sciences. Interdisciplinary research in epidemic preparedness and response [Internet]. London: Acmedsci; 2019 [citado 19 Jun 2022]. Disponível em: https://acmedsci.ac.uk/policy/policy-projects/multidisciplinary-research-in-epidemic-preparedness-and-response-
https://acmedsci.ac.uk/policy/policy-pro...

31 Bardosh KL, Vries DH, Abramowitz S, Thorlie A, Cremers L, Kinsman J, et al. Integrating the social sciences in epidemic preparedness and response: a strategic framework to strengthen capacities and improve Global Health security. Global Health. 2020; 16(1):1-18.

32 Stephen C. Rethinking pandemic preparedness in the Anthropocene. Healthc Manage Forum. 2020; 33(4):153-7.

33 Nunes MO, Deslandes S, Verdi MIM, Harayama RM, Leão LHC, Silva MBB, et al. A research agenda for the Social and Human Sciences during the Covid-19 pandemic. Cad Saude Publica. 2021; 37(10):e00158421.^-3434 Corsi M, Ryan JM. What does the Covid-19 crisis reveal about interdisciplinarity in social sciences? Int Rev Soc. 2022; 32(1):1-9., in the constitutive sphere of Collective Health, Epidemiology was the area that was most promptly and intensely required to manifest itself³⁵35 Nature. How epidemiology has shaped the Covid pandemic. Nature. 2021; 589(7843):491-2., a pattern already detected in other epidemic situations³¹31 Bardosh KL, Vries DH, Abramowitz S, Thorlie A, Cremers L, Kinsman J, et al. Integrating the social sciences in epidemic preparedness and response: a strategic framework to strengthen capacities and improve Global Health security. Global Health. 2020; 16(1):1-18.. The prominence of Epidemiology can have different explanations: greater institutionalization of epidemiological practices in health services; familiarity with biomedical concepts³¹31 Bardosh KL, Vries DH, Abramowitz S, Thorlie A, Cremers L, Kinsman J, et al. Integrating the social sciences in epidemic preparedness and response: a strategic framework to strengthen capacities and improve Global Health security. Global Health. 2020; 16(1):1-18.; training in epidemics investigation³¹31 Bardosh KL, Vries DH, Abramowitz S, Thorlie A, Cremers L, Kinsman J, et al. Integrating the social sciences in epidemic preparedness and response: a strategic framework to strengthen capacities and improve Global Health security. Global Health. 2020; 16(1):1-18.; specific knowledge of building forecast scenarios for the spread of Covid-19³³33 Nunes MO, Deslandes S, Verdi MIM, Harayama RM, Leão LHC, Silva MBB, et al. A research agenda for the Social and Human Sciences during the Covid-19 pandemic. Cad Saude Publica. 2021; 37(10):e00158421.; greater importance given to the scientific capital of Epidemiology due to its numerical predominance; and, consequently, occupation in the decision-making spheres of prestige assessment³⁶36 Deslandes S, Moraes CL, Maksud I, Marques ES, Bosi MLM, Ianni AMZ. Distribuição dos capitais científicos entre docentes permanentes de Ciências Sociais e Humanas e de Epidemiologia do campo da Saúde Coletiva. Cad Saude Publica. 2021; 37(11):e00278620..

The unprecedented and broad engagement of the entire community of epidemiologists in the response to the pandemic has brought many issues to light. One of them was the reemergence of theoretical and political tensions between Epidemiology and the other structuring sub-areas of Collective Health: Social and Human Sciences in Health, and Health Policies, Planning, and Management³⁷37 Teixeira CFS. Challenges of health surveillance today. Epidemiol Serv Saude. 2022; 31(2):e2022357.. It is evident that Epidemiology has had a greater weight in consultations with specialists related to decision-making about public policies related to the Covid-19 pandemic when compared to the Social Sciences - which have been historically sidelined³⁸38 Lohse S, Canali S. Follow *the* science? On the marginal role of the social sciences in the Covid-19 pandemic. Eur J Philos Sci. 2021; 11(4):1-28.. Right in the outset of the pandemic, the Brazilian Collective Health Association (Abrasco) perceived this discomfort in its community and tried to act on several fronts. First, it denounced the exclusion of themes related to the Social and Human Sciences from Notices for the public funding of research in the context of the Covid-19 pandemic³⁹39 Flaeschen H. Precisamos das Ciências Sociais e Humanas para compreender e enfrentar a pandemia de Covid-19 [Internet]. Rio de Janeiro: Abrasco; 2020 [citado 19 Jun 2022]. Disponível em: https://www.abrasco.org.br/site/noticias/saude-da-populacao/nota-precisamos-das-ciencias-sociais-e-humanas-para-compreender-e-enfrentar-a-pandemia-de-covid-19/47225/
https://www.abrasco.org.br/site/noticias... . Second, it promoted debates on the theme in the sphere of “Ágora Abrasco”, a program of activities that aimed to monitor, discuss, and propose responses to the pandemic⁴⁰40 Dias BC. Ágora Abrasco, uma nova forma da Saúde Coletiva produzir respostas à pandemia [Internet]. Rio de Janeiro: Abrasco; 2020 [citado 19 Jun 2022]. Disponível em: https://www.abrasco.org.br/site/noticias/institucional/agora-abrasco-uma-nova-forma-da-saude-coletiva-produzir-respostas-a-pandemia/46521/
https://www.abrasco.org.br/site/noticias... .

As I highlighted above, because of its domain of activity, objectives, concepts and methods, and mainly due to the influence of “risk factor epidemiology” on its scientific practice, Epidemiology has used, more frequently, theories on the mechanisms that cause health events to the detriment of theories on the distribution of health problems in populations to interpret the outcomes of its studies⁴4 Krieger N. Epidemiology and the people’s health: theory and context. New York: Oxford University Press; 2011.. The subtlety of the differences has huge implications. Theories on causal mechanisms of diseases and other health events are important to generate knowledge that can be eventually translated, but do not meet the need of understanding how and why these events are distributed unevenly in different populations over time and space⁴4 Krieger N. Epidemiology and the people’s health: theory and context. New York: Oxford University Press; 2011.. A simplistic way of interpreting the integration difficulties between Epidemiology and the Social and Human Sciences would be to attribute to Epidemiology an intrinsic link to the biomedical explanation model of health phenomena, which does not do justice to the historical connections between Epidemiology and the Social Sciences⁴¹41 Krieger N. Epidemiology and social sciences: towards a critical reengagement in the 21st century. Epidemiol Rev. 2000; 22(1):155-63..

Epidemiology does not identify itself inherently and preferentially with the biomedical explanation model of health phenomena, nor does it have difficulties in exercising interdisciplinarity or focusing on complex theoretical issues. Modern Epidemiology may be insufficient for the dimension of the mission of the Epidemiology that we want and need in Collective Health, but it allowed theoretical, conceptual, and methodological advances that were essential to the maturation and consolidation of the area. Furthermore, it required interactions not only with biomedical disciplines, but also with fields as different as philosophy, artificial intelligence, and computer sciences⁴²42 Struchiner CJ. A síndrome da gafieira (quem está fora não entra e quem está dentro não sai): comentários a “por uma epidemiologia da saúde coletiva”. Rev Bras Epidemiol. 1998; 1(2):125-7.^,4343 Porta M, Vineis P, Bolúmar F. The current deconstruction of paradoxes: one sign of the ongoing methodological “revolution”. Eur J Epidemiol. 2015; 30(10):1079-87.. Establishing that Modern Epidemiology is the sole paradigm of Epidemiology is a mistaken and little constructive idea, as it ignores the vigor of different movements within the area that seek to recover the roots of critical Latin American Epidemiology and aim to stimulate a greater integration with the Social and Human Sciences²2 Breilh J. Critical epidemiology and the people’s health. New York: Oxford University Press; 2021.^,44 Krieger N. Epidemiology and the people’s health: theory and context. New York: Oxford University Press; 2011.^,4444 Roux AVD. Social epidemiology: past, present, and future. Annu Rev Public Health. 2022; 43:79-98.. In fact, the pandemic has revealed a plural Epidemiology, which harbors approaches that have more disciplinary emphases and participates in a varied range of efforts to form and produce interdisciplinary knowledge and practices⁴⁵45 Braune K, Rojas P-D, Hofferbert J, Sosa AV, Lebedev A, Balzer F, et al. Interdisciplinary online hackathons as an approach to combat the Covid-19 pandemic: case study. J Med Internet Res. 2021; 23(2):e25283.^,4646 Carter S, Moncrieff IS, Akilimali PZ, Kazadi DM, Grépin KA. Understanding the broader impacts of Covid-19 on women and girls in the DRC through integrated outbreak analytics to reinforce evidence for rapid operational decision-making. Anthropol Action. 2022; 29(1):47-59.. In Brazil, in the current pandemic context, I highlight the initiatives of Rede CoVida⁴⁷47 Cidacs/Fiocruz, UFBA. Rede CoVida - Ciência, Informação, Solidariedade [Internet]. Salvador: RedeCovida; 2022 [citado 19 Jun 2022]. Disponível em: https://redecovida.org/sobre/
https://redecovida.org/sobre/... and Observatório Covid-19 BR⁴⁸48 Observatório Covid-19 BR. Sobre [Internet]. Rio de Janeiro: Covid19Br; 2022 [citado 19 Jun 2022]. Disponível em: https://covid19br.github.io/sobre
https://covid19br.github.io/sobre... , among others.

Balancing the role of the different axes of Collective Health in health emergency situations is a practical need, but it must also be a fundamental principle and a requirement to the very field of Collective Health. This is no simple task. Tensions between (sub)areas are part of the very constitution of the field, but it is in this process that Collective Health can be strengthened, and the benefits to population health, maximized.

A committed, engaged, and challenged Epidemiology

The strength of the Brazilian Epidemiology had already been noted in other occasions; for example, in the response to the Zika epidemic⁴⁹49 Machado-Silva A, Guindalini C, Fonseca FL, Pereira-Silva MV, Fonseca BP. Scientific and technological contributions of Latin America and Caribbean countries to the Zika virus outbreak. BMC Public Health. 2019; 19(1):530.^,5050 Oliveira JF, Pescarini JM, Rodrigues MS, Almeida BA, Henriques CMP, Gouveia FC, et al. The global scientific research response to the public health emergency of Zika virus infection. PLoS One. 2020; 15(3):e0229790.. However, in no other situation was the total and intensive engagement of the entire community so evident, regardless of its specific areas of activity. Thus, the Brazilian Epidemiology’s response to the pandemic is a tribute to its origins and social commitment, and shows that it is essential to the field of Collective Health.

To the generations of epidemiologists that graduated in recent decades, this may have been the first concrete experience of the simultaneously scientific and applied nature of Epidemiology. In the midst of personal and professional uncertainties, of fear and mourning, never before have so many epidemiologists committed so strongly to one mission⁵¹51 Swanson SA. The lived experiences of epidemiologists in 2020. Epidemiology. 2021; 32(1):131.. With this in mind, the journal “Epidemiology” payed homage to the area: it published a special issue with the report of twenty epidemiologists on their experiences of what being an epidemiologist in 2020 meant for them⁵¹51 Swanson SA. The lived experiences of epidemiologists in 2020. Epidemiology. 2021; 32(1):131.. The experiences of these epidemiologists, their daily difficulties to adapt to remote education and domestic chores, and their efforts to gain knowledge on specific concepts of infectious disease Epidemiology are assets that must not be lost and can play an important role in shaping the future of the area⁵¹51 Swanson SA. The lived experiences of epidemiologists in 2020. Epidemiology. 2021; 32(1):131..

This process of immersion in and exposure of the epidemiologist’s work reflects a recognition of the area and, at the same time, has brought many challenges, frustrations and uncertainties - which are always potential sources of learning. Regarding the epidemiologist’s work, the Covid-19 pandemic triggered new discussions and debates about the mission and ethics of Epidemiology research and practice. The debate about whether the existence of a neutral and disinterested epidemiology-science is possible has been renewed, which, in a way, revives the old questionings about “risk factor epidemiology”⁵²52 Savitz DA. Point: reconciling epidemiology’s aspirations and capabilities. Am J Epidemiol. 2021; 190(6):977-9.^,5353 Saracci R. Counterpoint: epidemiology’s dual social commitment-science and health. Am J Epidemiol. 2021; 190(6):980-3.. Declarations from groups for and against different pandemic control strategies have also agitated the academic Epidemiology circles, taking the debate to the ethical and social field⁵⁴54 Kupferschmidt K. A divisive disease. Science. 2020; 370(6523):1395-7.. Various factors, like the increased publication speed of Covid-19 papers, the high frequency of scientific paper retractions, even in journals considered exemplary in editorial terms, and the broad use of platforms for the dissemination of preprints, have enhanced the concern about the growth of practices incompatible with ethics in scientific publication⁵⁵55 Anderson C, Nugent K, Peterson C. Academic journal retractions and the covid-19 pandemic. J Prim Care Community Health. 2021; 12:1-6.^,5656 Schonhaut L, Costa-Roldan I, Oppenheimer I, Pizarro V, Han D, Díaz F. Scientific publication speed and retractions of Covid-19 pandemic original articles. Rev Panam Salud Publica. 2022; 46:e25..

In the applied sphere, central canons of Science and of Epidemiology itself started to be disputed, like the need to ponder to what extent the pandemic context authorizes relativization of the type and degree of evidence usually required to make a Public Health recommendation, which somehow made the principle of precaution conflict with the principle of not causing damage to health nor to other spheres of social life, like education⁵⁷57 Baral SD, Mishra S, Diouf D, Phanuphak N, Dowdy D. The public health response to Covid-19: balancing precaution and unintended consequences. Ann Epidemiol. 2020; 46:12-3.^,5858 Ioannidis JPA. Coronavirus disease 2019: the harms of exaggerated information and non-evidence-based measures. Eur J Clin Invest. 2020; 50(4):e13222.. Using incomplete information to support decision-making can be uncomfortable for epidemiologists, but the urgency of the situation demands using the best evidence available at a certain moment, synthesized from different sources⁵⁹59 Edwards JK, Lessler J. What now? Epidemiology in the wake of a pandemic. Am J Epidemiol. 2021; 190(1):17-20.. It is important to understand that the epidemiologist’s work does not end when decisions are made - they must evaluate how events evolve by means of recommendations in order to update knowledge to shift direction, if necessary⁵⁹59 Edwards JK, Lessler J. What now? Epidemiology in the wake of a pandemic. Am J Epidemiol. 2021; 190(1):17-20..

One example of this clash was the closure of schools right at the outset of the pandemic, with unprecedented duration and amplitude. In the absence of solid knowledge on the role of children in the transmission of SARS-CoV-2, the implementation of this measure was largely based on the analogy with influenza pandemics, when it was demonstrated that school closure can reduce the size of the epidemic⁶⁰60 Nafisah SB, Alamery AH, Nafesa AA, Aleid B, Brazanji NA. School closure during novel influenza: a systematic review. J Infect Public Health. 2018; 11(5):657-61.. However, such measure brings high social and economic costs, especially to vulnerable populations, intensifying educational disparities and increasing school dropout, not to mention its deleterious impact on child nutrition, on parents’ and children’s Mental Health, and on exposure to violence⁶¹61 United Nations Educational, Scientific and Cultural Foundation - UNESCO. Adverse consequences of school closures [Internet]. Paris: Unesco; 2020 [citado 19 Jun 2022]. Disponível em: https://en.unesco.org/covid19/educationresponse/consequences
https://en.unesco.org/covid19/educationr... . In this topic, it is worth highlighting the joint participation of researchers from Epidemiology, Social and Human Sciences in Health, and Postgraduate Programs in Collective Health, under the leadership of Abrasco, of the National Association for Postgraduate Programs and Research in Education (ANPED), and of other Education organizations, in the consolidation of the manifesto “Occupying schools, protecting people, valuing education”, signed by dozens of civil society entities⁶²62 Abrasco. Ocupar escolas, proteger pessoas, valorizar a educação [Internet]. Rio de Janeiro: Abrasco; 2020 [citado 19 Jun 2022]. Disponível em: https://www.abrasco.org.br/site/wp-content/uploads/2020/10/MANIFESTO-_OCUPAR-ESCOLAS-PROTEGER-PESSOAS-RECRIAR-A-EDUCACAO_2-1.pdf
https://www.abrasco.org.br/site/wp-conte... .

Specialists also had to deal with questionings about the role of Epidemiology and, more generically, of scientific knowledge, in decisions about public policies. To their displeasure and frustration, epidemiologists discovered, tardily, that the maxim “follow the science” has limits, and that Science must research, discover, assess, inform, and advise, but the decision must be made by managers after hearing other actors and sectors of society⁶³63 Colman E, Wanat M, Goossens H, Tonkin-Crine S, Anthierens S. Following the science? Views from scientists on government advisory boards during the Covid-19 pandemic: a qualitative interview study in five European countries. BMJ Glob Health. 2021; 6(9):e006928.. Science alone does not change the world. Science, politics and social militancy walk together in the life of all people, and this includes us, epidemiologists.

Another great challenge, perhaps unprecedented in terms of scope and frequency, has been the presence of epidemiologists in the media. Scientific communication, the “ugly duckling”, so to speak, of academic activity, has proven to be essential and, clearly, beyond the capacities of most of us. The obstacles encountered are not just difficulties in explaining complex concepts - for these, the use of creative metaphors may be more viable. Other obstacles are related to a more effective communication about risk, especially about the uncertainties inherent in scientific work³⁵35 Nature. How epidemiology has shaped the Covid pandemic. Nature. 2021; 589(7843):491-2.^,3838 Lohse S, Canali S. Follow *the* science? On the marginal role of the social sciences in the Covid-19 pandemic. Eur J Philos Sci. 2021; 11(4):1-28.^,6363 Colman E, Wanat M, Goossens H, Tonkin-Crine S, Anthierens S. Following the science? Views from scientists on government advisory boards during the Covid-19 pandemic: a qualitative interview study in five European countries. BMJ Glob Health. 2021; 6(9):e006928.. For example, to the epidemiologist, talking about uncertainty overcomes the issue of randomness; it is also necessary to approach how biases can influence the credibility of research outcomes⁶⁴64 Banack HR, Lesko CR, Whitcomb BC, Kobayashi LC. Teaching epidemiology online (Pandemic Edition). Am J Epidemiol. 2021; 190(7):1183-9..

Communication about the principle of precaution was also difficult. It is necessary to perceive that certain control and mitigation measures require a great effort of people, and recommendations regarding their utilization in the context of a prolonged pandemic contribute to the so-called pandemic fatigue⁶⁵65 World Health Organization. Pandemic fatigue - reinvigorating the public to prevent Covid-19: policy framework for supporting pandemic prevention and management. Copenhagen: WHO Regional Office for Europe; 2020.^,6666 Haktanir A, Can N, Seki T, Kurnaz MF, Dilmaç B. Do we experience pandemic fatigue? Current state, predictors, and prevention. Curr Psychol. 2021; 1-12. doi: https://doi.org/10.1007/s12144-021-02397-w.
https://doi.org/10.1007/s12144-021-02397... . If the recommendations are not negotiated in a systematic way and, perhaps, made more flexible - even though this implies some additional risk -, society becomes frustrated, as it does not perceive the benefits of its efforts in daily life. Pandemic fatigue reduces the search for information related to Covid-19 and decreases adherence to control measures⁶⁵65 World Health Organization. Pandemic fatigue - reinvigorating the public to prevent Covid-19: policy framework for supporting pandemic prevention and management. Copenhagen: WHO Regional Office for Europe; 2020..

Another example of communication failure that must be debated in the area was the lack of consensus on the main ways Covid-19 is transmitted, which eventually led to the prioritization of little effective actions that may have contributed to pandemic fatigue (for example, the cleaning of materials, surfaces, and food items) to the detriment of the use of masks⁶⁴64 Banack HR, Lesko CR, Whitcomb BC, Kobayashi LC. Teaching epidemiology online (Pandemic Edition). Am J Epidemiol. 2021; 190(7):1183-9.. In addition, in the case of mask use, recommendations varied from use of cloth masks to the need of more effective filtering masks like FFP2 and N95, which may have contributed to confuse the population⁶⁴64 Banack HR, Lesko CR, Whitcomb BC, Kobayashi LC. Teaching epidemiology online (Pandemic Edition). Am J Epidemiol. 2021; 190(7):1183-9.. It is certain that part of the inconsistency was due to the perception that there was a shortage of high-quality masks for the health services environment, but another important factor was the delay in recognizing that SARS-CoV-2 is transmitted not only by droplets, but also by aerosols⁶⁷67 Lewis D. Why the WHO took two years to say Covid is airborne. Nature. 2022; 604(7904):26-31..

Finally, Epidemiology rarely succeeded in influencing the media and the political agenda, and the list of themes to be discussed was usually set in the opposite direction. In some situations, the political agenda cornered the epidemiological research agenda, as it seems to be the case of the use of chloroquine for treatment of Covid-19⁶⁴64 Banack HR, Lesko CR, Whitcomb BC, Kobayashi LC. Teaching epidemiology online (Pandemic Edition). Am J Epidemiol. 2021; 190(7):1183-9.. Despite the extensive interaction between Epidemiology and the media, the quality of the presentation of epidemiological data in these vehicles stills needs to improve⁶⁸68 Hammes LS, Rossi AP, Pedrotti LG, Pitrez PM, Mutlaq MP, Rosa RG. Is the press properly presenting the epidemiological data on Covid-19? An analysis of newspapers from 25 countries. J Public Health Policy. 2021; 42(3):359-72..

How to communicate risks and uncertainties in a transparent way, how to make control measures more flexible in situations of pandemic fatigue, and how to tackle fake news and influence agendas in the relationship with the media and civil society are incipient issues that need to be further debated and incorporated into Epidemiology education, both in the undergraduate and graduate levels.

Are we all epidemiologists?

Epidemiology has been placed in the center of attention by the media and in the public policy decision arena in the fight against the Covid-19 pandemic³⁵35 Nature. How epidemiology has shaped the Covid pandemic. Nature. 2021; 589(7843):491-2.. In the media in general, but also in social conversations, epidemiological terms are being used on a daily basis. It is as if, all of a sudden, all people have become epidemiologists⁶⁹69 Gouvea N. What has it meant for me to be an epidemiologist in 2020? Epidemiology. 2021; 32(1):144-5..

Apparently, this would be a positive sign of the popularization of the field, but it might, on the contrary, de-characterize Epidemiology if, suddenly, everyone starts giving opinions, interpretations and recommendations as if they were epidemiologists. I believe the most appropriate term to define this situation is ultracrepidarian, that is, a person who expresses opinions on matters outside the scope of their knowledge. The term “armchair epidemiologist” has also been employed in this sense⁷⁰70 Smith GD, Blastland M, Munafò M. Covid-19’s known unknowns. BMJ. 2020; 371:m3979.. Undoubtedly, epidemiologists are not the only ones who can use and explain technical concepts and terms typically used in the area. However, it is necessary to recognize and value Epidemiology as a defined area of knowledge, included in the field of Collective Health, operating in a particular domain, with its own objectives, concepts and methods, and requiring specific theoretical and practical education⁷¹71 Samet JM, Woodward A. On being an epidemiologist. Am J Epidemiol. 2019; 188(5):818-24.. This is fundamental for managers and the public in general to recognize its relevance and the necessary differentiation as a professional of the biomedical areas, which implies opportunities for qualified work.

One possible positive aspect of that public exposure may have been the dissemination of an academic and professional niche that can amplify people’s interest in gaining admission into the area. We have not yet reached the stage where a child tells their parents that they want to be an epidemiologist when they grow up; therefore, it is necessary to seize this opportunity to disseminate what it means to be an epidemiologist, what Epidemiology researches, and the role it plays in the health services and in society. Given the intrinsic and inherent relation between the Brazilian Epidemiology and Collective Health, this is a promising occasion to the entire field.

Therefore, it is necessary to take advantage of the pandemic legacy to rethink Epidemiology education in the undergraduate and graduate levels. The basic components of Epidemiology education usually involve development of critical thinking, acquisition of information for subsequent application to the academic or professional spheres, and consolidation of a professional identity⁷²72 August E, Trostle JA. Using writing assignments to promote critical thinking, learning and professional identity: the epidemiology workplace writing repository. J Public Health. 2018; 40(3):419-22.. Information acquisition implies the relation between student and content, commonly mediated by tutors. It can be maximized by means of digital technologies, which enhance flexibility, responsibility, cooperation, inclusion, democratization, orientation to the problem of interest, and interaction between postgraduate programs, students and teachers⁶⁴64 Banack HR, Lesko CR, Whitcomb BC, Kobayashi LC. Teaching epidemiology online (Pandemic Edition). Am J Epidemiol. 2021; 190(7):1183-9.^,7373 Das TM, Kaur G, Nematollahi S, Ambinder D, Shafer K, Sulistio M, et al. Medical education in the digital era: a new paradigm for acquiring knowledge and building communities. JACC Adv. 2022; 1(2):1-4.. In contrast, more traditional pedagogical approaches with synchronous, tutorial and practical interpersonal interaction are essential to encourage dialog and belongingness, and to develop sense of community and critical thinking⁶⁴64 Banack HR, Lesko CR, Whitcomb BC, Kobayashi LC. Teaching epidemiology online (Pandemic Edition). Am J Epidemiol. 2021; 190(7):1183-9.^,7373 Das TM, Kaur G, Nematollahi S, Ambinder D, Shafer K, Sulistio M, et al. Medical education in the digital era: a new paradigm for acquiring knowledge and building communities. JACC Adv. 2022; 1(2):1-4.. Digital technologies can contribute to increase representativeness and identification with the field; moreover, they can collaborate to remove geographical and social barriers⁷³73 Das TM, Kaur G, Nematollahi S, Ambinder D, Shafer K, Sulistio M, et al. Medical education in the digital era: a new paradigm for acquiring knowledge and building communities. JACC Adv. 2022; 1(2):1-4.. Studies have shown that hybrid strategies, like flipped classrooms, help improve the quality and effectiveness of teaching and foster the development of autonomy, problem-solving skills, teamwork, and communication⁶⁴64 Banack HR, Lesko CR, Whitcomb BC, Kobayashi LC. Teaching epidemiology online (Pandemic Edition). Am J Epidemiol. 2021; 190(7):1183-9.^,7474 Baytiyeh H. The flipped classroom model: when technology enhances professional skills. Int J Inf Learn Technol. 2017; 34(1):51-62.. In the Brazilian context, it is necessary to make specific policies to ensure digital inclusion in distance education. Caution and the establishment of criteria are also necessary, so that the dissemination of distance education platforms does not “authorize” the indiscriminate expansion of poor quality courses.

Two other pandemic legacies can be good to the future of Epidemiology. The first refers to the renewed interest in descriptive Epidemiology. Descriptive investigations are a constitutive part of epidemiological activity, particularly in its interface with the health services⁷⁵75 Werneck G. Epidemiologia descritiva: qualidade das informações e pesquisa nos serviços de saúde. Epidemiol Serv Saude. 2009; 18(3):205-7.. The term “descriptive epidemiology” took on a pejorative connotation that indicates a less scientific or sophisticated approach⁷⁶76 Barata RCB. O desafio das doenças emergentes e a revalorização da epidemiologia descritiva. Rev Saude Publica. 1997; 31(5):531-7.. However, descriptive studies are fundamental to the understanding of health problems, and pose challenges just as complex as or more complex than those faced in other types of epidemiological studies⁷⁵75 Werneck G. Epidemiologia descritiva: qualidade das informações e pesquisa nos serviços de saúde. Epidemiol Serv Saude. 2009; 18(3):205-7.^,7676 Barata RCB. O desafio das doenças emergentes e a revalorização da epidemiologia descritiva. Rev Saude Publica. 1997; 31(5):531-7.. During the pandemic, we were systematically introduced, almost on a daily basis, to simple moving averages or complex nowcasting models⁷⁷77 Bastos LS, Economou T, Gomes MFC, Villela DAM, Coelho FC, Cruz OG, et al. A modelling approach for correcting reporting delays in disease surveillance data. Stat Med. 2019; 38(22):4363-77. to describe the trends and geographical distribution of hospitalizations and deaths from Covid-19. We searched for lethality information according to the most affected age groups and investigated whether such distribution changed over time, which would indicate a change in the epidemic severity profile. We talked about investigation of cases and contact tracing, typical health surveillance measures that were underused in the fight against the pandemic in Brazil, but which are essential to the interruption of transmission networks⁷⁸78 Teixeira MG, Kerr LRFS, Ximenes RAA, Almeida RLF, Ichihara MY, Albuquerque MFM, et al. Fortalecer as atividades de informação e vigilância epidemiológica é essencial e urgente para reduzir a força de transmissão do SARS-CoV-2. Rev Bras Epidemiol. 2021; 24:e210049..

The second legacy was the rediscovery of infectious disease Epidemiology. The microbiological revolution that started in the 19^th century and the social, scientific and technological advances, particularly in the area of Health, substantially modified the population’s morbidity and mortality profile in the first half of the 20^th century, mainly in Global North countries⁷⁹79 Susser M. Epidemiology in the United States after World War II: the evolution of technique. Epidemiol Rev. 1985; 7(1):147-77.. The participation of infectious diseases in the burden of morbidity and mortality gradually decreased, while the opposite happened with chronic-degenerative diseases, accidents, and violence cases⁸⁰80 Reingold AL. Infectious disease epidemiology in the 21st century: will it be eradicated or will it reemerge? Epidemiol Rev. 2000; 22(1):57-63.. This panorama led to what has been recognized as the healthcare optimism of the 20^th century: an inexorable march towards the eradication or elimination of infectious diseases as Public Health problems⁸⁰80 Reingold AL. Infectious disease epidemiology in the 21st century: will it be eradicated or will it reemerge? Epidemiol Rev. 2000; 22(1):57-63.. This process led to a decrease in interest in the area of infectious disease Epidemiology, which resulted in a drastic reduction in the number of professionals and research studies⁸⁰80 Reingold AL. Infectious disease epidemiology in the 21st century: will it be eradicated or will it reemerge? Epidemiol Rev. 2000; 22(1):57-63.. Unfortunately, the idea that infectious diseases would be simply crossed off history and replaced by other types of health problems was proved to be wrong. In fact, from the 1970s onwards, many unknown infectious diseases and others believed to have been eliminated have been largely affecting populations, and the advent of AIDS may be one of the most significant milestones of this shift in direction.

During the Covid-19 pandemic, basic concepts of infectious disease epidemiology were disseminated without the necessary rigor, which led to a series of misunderstandings and mistaken opinions about the pandemic process. Most epidemiologists involved in the effort of fighting against the pandemic were not adequately familiarized with concepts like herd or collective immunity, basic and effective reproduction number, serial interval, secondary attack rate, transmissibility and its implications. The question now is not “if” a new pandemic caused by an unknown microorganism is going to happen, but “when” it will happen⁸¹81 Wolfe N. The viral storm: the dawn of a new pandemic age. New York: Times Books; 2011.. Therefore, it is important to include such basic concepts in the epidemiologist’s education. Considering the scenarios of climate change and growth of natural and technological disasters⁸²82 Freitas CM. Acidentes industriais ampliados: riscos e estratégias de prevenção. Rio de Janeiro: Fundação Oswaldo Cruz; 2021., including epidemics and pandemics, such themes must be approached in undergraduate and graduate Collective Health programs.

Conclusions

The Covid-19 pandemic can be considered a large natural experiment⁵⁹59 Edwards JK, Lessler J. What now? Epidemiology in the wake of a pandemic. Am J Epidemiol. 2021; 190(1):17-20. with potential for causing substantial changes in different spheres of life, including the academic one. Epidemiology can use the experiences accumulated in this period as an opportunity to plan its future. The pandemic years have shown that knowledge of Public Health tools and access to data are not enough to control a pandemic³⁵35 Nature. How epidemiology has shaped the Covid pandemic. Nature. 2021; 589(7843):491-2.: it is necessary to produce explanatory theories about the pandemic process. Such theories must consider temporal and spatial heterogeneities of biological and social phenomena that allow an unequal manifestation of the pandemic in the population. To achieve this, Epidemiology needs, at the same time, to strengthen its scientific foundations, recognize the values and limits of its approaches, and understand that tools and techniques are not what ground transformative knowledge. In this path, it is essential to start from effective experiences of interdisciplinary action to overcome chronic obstacles that hinder the strengthening of links with other disciplines. A new teaching model can be produced from the experiences accumulated during the pandemic. This new model must encompass transversal contents, like preparation for responses to natural and technological disasters, including epidemics and pandemics, and scientific communication. Epidemiology teaching needs to be contextualized in the bases of Collective Health, and its commitment to translating and applying knowledge to improving people’s health and life must be reinforced.

Acknowledgments

To Professor Hillegonda Maria Dutilh Novaes for encouraging the writing of this text and to Professor Tânia Maria de Araújo for the inspiration and revision of the manuscript.

References

Publication Dates

History