Background: Since its identification in New York in 1999, West Nile virus (WNV) appears to have become endemic in the northeastern U.S. No human cases of WNV were detected in New Jersey by passive surveillance in 1999, although 62 cases were detected in nearby New York counties. In 2000, the New Jersey Department of Health and Senior Services (NJDHSS) implemented active surveillance to detect human WNV cases. Methods: Active hospital-based surveillance identified patients admitted with aseptic meningitis or encephalitis in 42 hospitals in six New Jersey counties. Passive surveillance was conducted by requesting that medical care providers report suspected cases to the NJDHSS. For patients who met WNV testing criteria, the NJDHSS tested for presence of IgM and IgG by enzyme immunoassays. We compared results from the two systems according to number of patients tested and WNV cases detected. Results: Active surveillance yielded a 71.4% median weekly response rate from participating hospitals. Ninety-nine meningitis and encephalitis cases were identified through active surveillance; 134 were reported through passive surveillance. Fifty-five New Jersey residents met WNV testing criteria. Five of 44 passively reported residents tested positive whereas one of 11 residents identified solely through active surveillance tested positive. Conclusions: The majority of patients who tested positive for WNV in New Jersey were identified through passive surveillance. Active surveillance neither achieved complete hospital participation nor captured all hospital-admitted meningitis and encephalitis cases. Active surveillance may not be as effective as passive surveillance for detecting WNV cases. Key words: surveillance, West Nile virus
Learning Objectives: 1. Define methods of conducting human surveillance for West Nile virus at the state-level. 2. Understand methods of evaluating the utility of surveillance efforts. 3. Target efforts to meet objectives of West Nile virus human surveillance objectives at the state-level.
Keywords: Surveillance, Emerging Diseases
Presenting author's disclosure statement:
Organization/institution whose products or services will be discussed: None
I do not have any significant financial interest/arrangement or affiliation with any organization/institution whose products or services are being discussed in this session.