Population Processes and Dynamics of Infectious Diseases

By definition, the epidemiology (the between- host dynamics) of infectious diseases are population processes; rates of infection, the host and other factors contributing to the dissemination of pathogens and the contribution of vaccines or other interventions to controlling and limiting the magnitude and effects of emerging, endemic and epidemic diseases in human populations are the major variables.  There is also a strong laboratory base of contemporary infectious disease epidemiology. The identification of humans currently and previously infected with particular pathogens, the nature and source of the infecting pathogen  (genetic or molecular epidemiology) the susceptibility of that pathogen to chemotherapeutic agents and the immune status of infected and uninfected people all involve population and laboratory based surveillance and often the sophisticated technology of molecular biology.

Traditionally, epidemiologists and laboratory-based investigators who provide data needed for models, surveys, predictions and prescriptions have been separately trained and performed different tasks, often with only modest if any appreciation of the needs and limitations of the other enterprise.  To address this issue, graduate students interested in the mathematical modeling and other elements of the population process of infectious disease will have training in infectious disease surveillance, biostatistics, case control, cohort and other analytical epidemiological studies as well as hands-on research experience in the appropriate laboratory of their co-mentor.  Graduate students conducting empirical work on molecular epidemiology, immunology, drug resistance, pathogenesis with interests in the epidemiology of infectious disease will have similar training and conduct research with an epidemiologist co-mentor.

Within a host the course, consequence and clearance of an infection are the result of proliferating and evolving populations of bacteria, viruses and other parasites interacting with populations of the somatic cells of the constitutive and inducible immune systems and the infected tissues.  The population and evolutionary dynamic elements of the within-host biology of infections is also fundamental to infectious diseases.  These processes may be recognized by epidemiologists, microbiologists, immunologists, biochemists, molecular biologists and pharmacologists, working on infectious diseases and their treatment.  However, it is rare that they approach the study of infectious diseases pathogenesis, prevention and treatment in this light.  On the other side, population and evolutionary biologists working on infectious diseases often have little understanding of or training in human populations and also may lack important understanding of the biochemistry, molecular biology, physiology and microbiology of viral and bacterial or parasite infections, the immune response or the pharmacology of drug treatment.

To deal with this disconnect, students working on the within host biology of infections at a population dynamic and evolutionary level will, via the core courses and the dual mentorship program, also have the opportunity to work with epidemiologists, microbiologists, immunologists, molecular biologists and other investigators working on surveillance and molecular epidemiology and those studying the mechanisms of pathogenesis and the immune response.  Students working on the microbiology, immunology and molecular biology of infectious diseases will, via the core courses and the dual mentorship program work with epidemiologists and theoretical or experimental population biologists studying infectious diseases.

Professors Bruce Levin, Dr. Juan Leon, and Dr. Joanna B. Goldberg are co-directors of this track.