Marlissa came to writing fiction relatively late in life. At the great age of 41 she decided she needed some new challenges, and so took up horseback riding and writing short stories. A few falls later, she's still pursuing both activities. She seems to be doing a sideways drift from SF into horror, but has kept her fascination with the history of medicine, public health, and infectious disease. 
In her other life, Marlissa has a Ph.D. in Physical Anthropology, specializing in embryology. She spent several years pursuing laboratory research at the National Institutes of Health in Bethesda Maryland, during which time she acquired an English husband. After a stint as a regulatory toxicologist with the U.S. Environmental Protection Agency, specializing in chemical causes of birth defects and fertility problems, she accompanied said husband back to the UK. While there, she gave birth to two dual-citizen children, worked as a science advisor for the British National Farmers' Union, and earned a certificate in environmental impact assessment from the University of Wales, Aberystwyth. Currently she's back near where she grew up, living with her family on the San Mateo County coast, and working for the California Environmental Protection Agency.
If you're curious about current and likely future influences on her writing, check out her reading blog, "The Plague Docs"