What is missing thus far is a program that will enable us to perform scientific studies in the setting of an epidemic. Hence in this study, we will, in collaboration with the Program in Emerging Infectious Diseases (EID) in Duke-National University of Singapore Postgraduate Medical School, attempt to (i) detect novel, previously undescribed pathogens; (ii) characterize viruses (not necessarily novel but emerging and re-emerging) that are raising concern or causing clusters or epidemics in the hospital and/or country; (iii) characterize immune responses to such viruses in healthcare workers as well as patients (those affected by these viruses and those exposed to the affected). The techniques that will be used will be those not routinely available in a hospital's service labs.