pathogens such as Salmonella to the potentially disastrous, such as smallpox and anthrax. The health department receives reports by traditional phone, mail, and fax and—following a significant recent investment—by electronic and web-based methods as well. Participation in an electronic clinical laboratory reporting system, a secure network that allows DOHMH to receive laboratory-confirmed diagnoses in a timely manner, is mandated for all laboratories that diagnose New York City residents. This system enables DOHMH to spot citywide and neighborhood disease trends in routinely reported data that an individual physician would not be able to recognize, Layton said.
Upon receiving a report, DOHMH initiates an investigation to examine risk factors for infection in order to determine disease transmission routes, and, if appropriate, to arrange prophylaxis. “The most important thing we try to do is to make sure that every health care provider knows who and how to call to make a report,” Layton said.
In the event of an apparent or actual public health emergency, New York City’s health alert system quickly disseminates information to providers on the nature of the emergency and instructions on preparing and delivering diagnostic specimens. Because New York City is at high risk for receiving imported disease, DOHMH stays attuned to global infectious disease issues via surveillance networks such as ProMED-mail (see Morse in Chapter 2) and responds to reports of significant disease activity abroad by ramping up surveillance and alerting health-care providers in New York City to look for signs of an outbreak. After an outbreak of West Nile virus in 1999, and in light of increasing concern regarding the potential use of zoonotic diseases as bioterrorism agents, animal diseases were made reportable in New York City in 2000.
DOHMH has invested considerable hospital-preparedness funding to improve the ability of triage systems to recognize patients with significant risk factors for infectious disease, particularly patients with fever and respiratory illness who have traveled recently. This is crucial because, in Layton’s words, “New York City could be the next Toronto, with an unrecognized imported outbreak of severe acute respiratory syndrome (SARS)—or of bioterrorism, E. coli, or most worrisome of all, avian influenza.”
The realization that many unreported, hospitalized cases of viral encephalitis (a reportable disease) manifested during the West Nile virus outbreak caused DOHMH to adopt procedures to monitor similar nonspecific clinical syndromes. In 1998, the city began syndromic surveillance based on ambulance dispatch data; the system was expanded to monitor the entire emergency department in the wake of the 2001 World Trade Center attack, then further to monitor pharmacy sales, employee health, school absenteeism, and primary care visits. One of the most challenging aspects of responding to a syndromic signal is getting specimens to a lab for diagnostic testing, Layton observed, particularly specimens from the acutely ill patients typically seen in emergency departments. Rapid diagnostic testing is performed for a variety of pathogens at a single New