Janka Petravic is a theoretical physicist who, after several years of work in the field of computational physics of liquids, changed the focus of her research to modelling infectious diseases, with primary interests in the within-host interaction between a pathogen and the immune system in HIV infection and malaria. The perspective of her models ranges from the cell invasion by the pathogen, to the disease-response dynamics within the body and finally to the epidemiological implications. The models are firmly grounded in data in order to maintain clinical relevance. Since recently, she is working at the Burnet Institute in Melbourne on the epidemiology of malnutrition in low- and middle-income countries.