Rasmussen joined the faculty at
Columbia University Mailman School of Public Health, where she worked as an associate research scientist. There, she studied how hosts respond to infectious diseases such as
SARS and
Ebola.
Ebolavirus research During her tenure at
University of Washington, she studied the response of mice to
ebolavirus infection. The traditional mouse model, derived from a uniform genetic background, dies before the classical symptoms of the disease appear after infection, making it difficult to study the virus's pathogenesis. They concluded that the genetic background of the mice, therefore, plays a role in their susceptibility to the virus. By understanding which genes in mice affect the course of infection, researchers can better determine which genes make humans more susceptible to the disease—and why some humans die from an infection, while others survive. Rasmussen continued work on understanding genetic susceptibility with Ebola at
Columbia University. There, she identified a gene expression signature that may predict the severity of Ebola infection. Rasmussen and collaborators have also used human cell lines to investigate the course of infection. Upon infection,
ebolavirus first targets
macrophages, or white blood cells that engulf and clear away
pathogens, which in turn release
inflammatory cytokines that recruit more immune cells to the site of the infection to kill off infected tissue. If cytokine release goes unchecked it can lead to a profound
inflammatory response—known as a
cytokine storm—that can kill off healthy tissue, as is the case with an ebolavirus infection. She and collaborators found that inhibiting the inflammatory response of virus-infected macrophages could be a potential therapeutic target, preventing a cytokine storm from occurring.
COVID-19 work Rasmussen's work investigating the heterogeneity in Ebola infections has translated into developing hypotheses around why some COVID-19 cases are worse than others. She has also been on the frontlines of communication around the novel coronavirus and COVID-19, applying her expertise in correspondence with the popular press to interpret preliminary results around how long immunity to the virus may last, how effective potential drugs may be in treating the disease, and whether
biological sex plays a role in the severity of the disease. Given the breakneck pace at which preliminary research results have been released—for example, through
preprints—she has urged caution in reporting research findings too quickly, without proper caveats, to ensure the public is not misinformed. == Advocacy ==