In San Francisco, Mark Honigsbaum will examine the notebooks and correspondence of the Swiss-born pathologist and medical microbiologist Karl Friedrich Meyer (1884-1974) as part of a knowledge exchange with the chair of the department, Dr Brian Dolan, and Professor Dorothy Porter. Meyer, who was appointed associate professor of tropical medicine at the University of California medical school in 1915 and also held posts in pathology and bacteriology at UC Berkeley, was the preeminent medical researcher in the Bay Area throughout the 1920s and 1930s and a leading figure in US public health for more than five decades. At the Hooper Foundation for Medical Research, in Parnassus, where he was director from 1924, Meyer integrated epidemiological insights into the laboratory study of microbes. In the process, he forged a reputation as a prodigious "microbe hunter", spearheading investigations into poor canning practices (botulism) and diseases such as brucellosis, equine encephalitis, psittacosis, leptospirosis and sylvatic plague at the intersection of animal and human health. By 1950 these feats had seen him hailed as "the most versatile microbe hunter since Pasteur". In the 60 years since, this characterisation has gone largely unchallenged. However, in his writings and interviews, Meyer, who was educated at Basel and Zurich, showed himself to be a far from stereotypical microbe hunter. On the contrary, Meyer – "KF" to his friends – was one of the first medical researchers to refer to "animal reservoirs of disease" and to call for the reframing of infectious disease research in terms of "host-parasite" relationships. It is hoped that a close examination of Meyer's notebooks and letters at the Bancroft and UCSF libraries will result in a better understanding of his intellectual development and how he came to link microbial behavior to broader bio-ecological, environmental, and social factors that impact host-pathogen interactions and the mechanisms of disease control.