Sara Hägg, PhD, is a Researcher at the Department of Medical Epidemiology and Biostatistics at Karolinska Institutet (KI) in Stockholm, Sweden, where she is also a Docent in Molecular Epidemiology (Swedish teaching qualification degree). She did her undergraduate training at Stockholm University majoring in Molecular Biology (MSc) and Computer Science (BSc) and completed her thesis in Computational Biology (PhD) at Linköping University, Sweden, in 2009. Since 2015, Dr. Hägg has focused on molecular epidemiological studies of aging. In 2016, she was a visiting assistant professor at Stanford University. She has started working with geriatricians from hospitals in the Stockholm area studying frailty in old covid-19 patients. This work has now been extended and in collaboration with Professor Qi WANG and colleagues at the Huazhong University of Science and Technology, and they will study how the pandemic has affected the health of the older population in Wuhan and Stockholm.