Techniques of public health surveillance have been used in particular to study infectious diseases . Many large institutions , such as the WHO and the CDC , have created databases and modern computer systems ( public health informatics ) that can track and monitor emerging outbreaks of illnesses such as influenza , SARS , HIV , and even bioterrorism , such as the 2001 anthrax attacks in the United States
2001 anthrax attacks
2001 anthrax attacks
Public health surveillance