biowatch biowatch biowatch is a united states federal government program to detect the release of pathogens into the air as part of a terrorist attack on major american cities. reportedly operating in philadelphia, new york city, washington, dc, san diego, boston, chicago, san francisco, atlanta, st. louis, houston, los angeles and 21 other cities, the biowatch program was created in 2001 in response to the increased threat of bioterrorism sparked by the 2001 anthrax attacks, and was announced in president george w. bush's state of the union address of 2003. the program, described as "the nation's first early warning network of sensors to detect biological attack" operates via a system of filters located within existing environmental protection agency air filters that monitor air quality. results from these filters are analyzed by the centers for disease control and prevention, who pass any significant results to the federal bureau of investigation. as of mid-2012, the system had generated a large number of false positives (alerts that are determined to be naturally occurring and not terrorist releases), with more than 50 such cases documented between 2003 and 2008. state and local health officials have never ordered evacuations or distributed emergency medicines in response to a positive reading from the system. in an audit reported by associated press on march 4 2021, biowatch was said to have failed in detecting known threats, questioning the value of the program. history origins