Microbial Pathogenesis and Host Response September 21 – 25, 2021 ABSTRACT The thirteenth international conference on Microbial Pathogenesis and Host Response will focus on interdisciplinary approaches to study infectious disease, integrating the disciplines of molecular microbiology, eukaryotic cell biology, immunology, and genomics. Microbial diseases have once again taken an important central role in health care worldwide, due to the emergence of new pathogens, the re-ascent of common pathogens, and extensive drug resistance. Outside of human health, devastating pandemics are destabilizing ecosystems, with brown bats and amphibians currently under extreme threat. The meeting will provide an in- depth focus on the approaches that are being used to elucidate the mechanisms of bacterial and fungal pathogenesis, and promote the application of these concepts to novel strategies for the control and intervention of infectious diseases. Oral and poster sessions will focus on major emerging themes of microbial pathogenesis and the host response, including: the pathogenesis & evolution of microbial diseases; the regulation of pathogenesis, heterogeneity of pathogens as an adaptive mechanism, host cell/pathogen interactions, and the diversity of pathogen strategies to evade innate immunity. The sessions will integrate studies on bacterial and fungal pathogens. The oral sessions will begin with 2-3 invited talks by established leaders in the field, followed by several shorter talks chosen from submitted abstracts. Broad themes for individual sessions include: 1) pathogen coinfections; 2) cell biology of infections; 3) heterogeneity in pathogen and disease outcomes; 4) the diversity of pathogen evasion strategies of innate immunity; 5) microbial evolution and virulence; and 6) gastrointestinal ecology and microbial pathogenesis. The inclusion of two poster sessions as well as the allotment of ample time for questions following each talk will encourage extensive discussion between the participants. The meeting will be small enough (300 - 400 scientists) to facilitate these interactions, yet large enough to allow for oral presentations not only from established investigators, but also from junior investigators and those with novel perspectives. The integration of a wide variety of aspects of bacterial and fungal pathogenesis with the host response to pathogens should promote new interdisciplinary interactions that are seldom achieved at other meetings on microbial pathogenesis that are either more narrowly focused or so diverse that the topics are challenging to integrate. The resulting interdisciplinary interactions will facilitate the development of conceptual and experimental approaches that might not otherwise be possible.