Introduction

Since 2001, federal, state, and local public health and health care agencies have faced new challenges in surveillance, in light of the anthrax attack in 2001,¹ smallpox preparedness efforts,^2,3 the severe acute respiratory syndrome (SARS) outbreak in 2003,⁴ and other emerging infectious disease threats. Traditional public health surveillance relies on passive reporting from local public health and health care partners. Reports of unusual instances or clusters of illness or diseases with public health importance (e.g., disease caused by Neisseria meningitidis or Mycobacterium tuberculosis) are sent to the state health departments.

The New Jersey Department of Health and Senior Services’ (DHSS) Communicable Disease Service (CDS) is responsible for epidemiologic activities related to reportable communicable diseases per N.J.A.C. 8:57,⁵ as well as for public health issues and emergencies related to emerging infectious diseases. In addition, throughout New Jersey, twenty-two Local Information Network and Communications System (LINCS) epidemiologists are required to build relationships with their jurisdictions’ public health and health care partners to inform them of the state’s reporting expectations. These partners include emergency departments, infectious disease physicians, infection control professionals (ICPs), visiting nurse agencies, hospital laboratories, and communicable disease investigators from other health departments.

To enhance traditional passive surveillance efforts, the DHSS CDS has developed and implemented several surveillance systems, to assist in the early detection of sentinel events.

COMMUNICABLE DISEASE REPORTING AND SURVEILLANCE SYSTEM

Prior to 2001 local health departments, hospitals, health care providers, and laboratories reported notifiable communicable diseases to NJDHSS by sending paper reports of the cases. These case reports included patient demographic information and pertinent laboratory and clinical findings. During 2001, DHSS CDS implemented the Communicable Disease Reporting System (CDRS), a secure web-based, Centers for Disease Control and Prevention (CDC) specifications-compliant electronic reporting system, to replace paper-based reporting. In January 2006, DHSS CDS rolled out the second generation of CDRS called the Communicable Disease Reporting and Surveillance System (CDRSS), a patient-centric system with improved functionality.

To date, DHSS CDS has made the CDRSS available to all of New Jersey’s 22 LINCS regional health agencies, local health departments (LHDs) and acute care hospitals. The CDRSS also receives electronic data reports from one commercial laboratory (LabCorp). DHSS CDS is currently working on receiving electronic data reports from other commercial and hospital laboratories.

CDRSS has over 175 reports available to help users with workload and case management. As CDRSS users have become more familiar with the system, DHSS CDS and LHD staff have detected and confirmed several outbreaks and disease clusters (including the November 2006 multi-state E. Coli outbreak associated with Taco Bell). With these CDRSS data, public health staff is better able to identify spatial and temporal linkages in communicable disease outbreaks and implement timely and appropriate public health control measures.

In addition to using the CDRSS to manage data on reportable diseases, the DHSS CDS has used the CDRSS data to determine possible aberrations for each reportable disease. Applying prevalent disease surveillance methodologies,^6,7 such as the statistical technique known as cumulative sums (CUSUM), the DHSS CDS examines statewide communicable disease data on a weekly basis to detect aberrations in disease activity. For each of the state’s twenty-one counties, reportable disease cases diagnosed and reported in CDRSS during the most recent four weeks are compared with the historical baseline average (i.e., the average number of cases for eight periods: the corresponding four-week period, the prior four-week period, and the following four-week period for the past two years, as well as two four-week periods prior to the most recent four-week period). Weekly alerts are flagged for reports that exceed the baseline average plus two or more standard deviations. DHSS CDS staff and LINCS epidemiologists receive via e-mail summarized weekly reports and any generated alerts. DHSS CDS staff and LINCS epidemiologists then review these reports/alerts and investigate specifically flagged diseases to determine whether any epidemiologic links exist among the reported cases.