Infectious diseases continue to be a major cause of human suffering and mortality. While much research and training has focused on studying infectious disease at a single scale (e.g. within hosts or at the population level), a major challenge in the control of infectious diseases is that they routinely operate across scales. Specifically, the interactions between host immune molecules and pathogens determine their transmission at the population level, which in turn determines the spread of diseases across regions; in addition, a major feature of emerging infectious diseases is that they infect a wide variety of non-human hosts, complicating their control. Consequently, in order to effectively understand and control infectious diseases, we need to integrate cross-scale approaches that span the full range of biological organization, from molecules to global ecosystems. 

Emerging and re-emerging infectious diseases represent one of the major threats to human health and well-being in the 21st century. Prominent examples of emerging infectious diseases often of zoonotic origin and/or vector transmission include Ebola, Zika, SARS, West Nile, Avian Flu, Hantaviruses, Nipah and many others. Re-emerging or continuously prevalent infectious diseases of massive global health impact include HIV, malaria, tuberculosis, leishmania, schistosomiasis, trypanosomiasis, and many others. In many instances increasing rates of contact between humans, agricultural animals and wildlife populations, combined with anthropogenic degradation of habitats and global warming, will increase the rate at which zoonotic outbreaks occur, and the likelihood that they develop in full-blown pandemics. At the same time ongoing issues such as poverty, lack of adequate health care infrastructure, social instability and inequality, and the impact of anti-scientific views (i.e., anti-vaccine movement) favor the re-emergence of disease that have been afflicting the human population for decades or centuries. Of note, there are still large gaps in our knowledge of many molecular aspects of the host-pathogen interactions (i.e., evolutionary epidemiology of pathogens and comparative immunology), the ecological interactions and the feedback mechanisms between different scales of biological organization that lead to the emergence of these diseases and their clinical and epidemiological impact on the human population worldwide. Notably, a firm integration of host-pathogen interactions across different scales will be necessary to enhance our understanding of disease dynamics and control; these range from the molecular interactions between pathogens and immune molecules, to pathogen-microbiome interactions within hosts, to transmission at the population level, ecological species interactions at the community level and human mobility at the regional and global level.

The current challenges to controlling infectious diseases require an innovative, pro-active, comprehensive, and cross-disciplinary approach. Currently, the global public health response to emerging and re-emerging infectious diseases is largely reactive, and consists of responding to outbreaks and/or increased incidence with the goal of containing these phenomena locally to prevent larger or global consequences. However, to more effectively control both emerging and re-emerging disease the establishment of a pro-active approach for action is desirable. Such an approach will consist of a comprehensive framework that starts at the mechanistic level with studies of molecular pathogenesis of the host pathogen interaction, definition of novel targets for anti-infectious drugs and vaccines, all the way to the definition and clinical and epidemiological implementation of novel preventative and therapeutic interventions for these infectious diseases. This framework will involve a cross-disciplinary strategy that includes expertise in basic, translational, and clinical microbiology and immunology, studies of pathogen reservoirs at the ecosystem level, expertise in population dynamics, epidemiology and public health, and ultimately the clinical and prophylactic implementation of the ensuing concepts and approaches. The goal of this innovative approach is to reduce the relative risks of future human suffering caused by emerging and re-emerging infectious diseases. While the focus is on understanding and curbing infectious diseases, this requires an expansion and refocus on basic scientific research. In particular, Figure 1 outlines some of the basic questions that need to be addressed to effectively realize this research program. As outlined in figure 1, important processes between scales are bidirectional: for example, while within-host interactions between the microbiome and pathogens determine pathogen spread in the population, population-level processes, such as host heterogeneity in resistance (e.g., because of naturally occurring variation or vaccine campaigns) feed back into the occurrence of such within-host interactions. These processes are complex and non-linear and require the development of new statistical and mathematical tools to enhance understanding and prediction. Establishing this novel framework will ultimately allow us to predict where and when the next outbreaks of disease will occur, and thereby prevent them from happening in the first place.

Figure 1

The goal of the MP3 Initiative is to facilitate and grow basic and applied infectious disease research across scales at Emory University, from molecules and pathogens within hosts to populations and pandemics. The main way in which the initiative will accomplish is to provide sizable seed grants to interdisciplinary teams of researchers, to provide proof-of-concept and preliminary results for subsequent applications for research grants, program grants, center grants and training grants. An explicit requirement of funding through this program is therefore the subsequent submission of extramural grants. Importantly, to fully establish interdisciplinary research programs, seed grants are only awarded to teams of researchers from different schools at Emory University. Furthermore, partnerships with the Centers for Disease Control and Prevention and the Carter Center are strongly encouraged.