Updated guidelines for evaluating public health surveillance systems: recommendations from the Guidelines Working Group.

The purpose of evaluating public health surveillance systems is to ensure that problems of public health importance are being monitored efficiently and effectively. CDC's Guidelines for Evaluating Surveillance Systems are being updated to address the need for a) the integration of surveillance and health information systems, b) the establishment of data standards, c) the electronic exchange of health data, and d) changes in the objectives of public health surveillance to facilitate the response of public health to emerging health threats (e.g., new diseases). This report provides updated guidelines for evaluating surveillance systems based on CDC's Framework for Program Evaluation in Public Health, research and discussion of concerns related to public health surveillance systems, and comments received from the public health community. The guidelines in this report describe many tasks and related activities that can be applied to public health surveillance systems.

Surveillance for asthma--United States, 1960-1995.

PROBLEM/CONDITION: Asthma is one of the most common chronic diseases in the United States, and it has increased in importance during the preceding 20 years. Despite its importance, no comprehensive surveillance system has been established that measures asthma trends at the state or local level. REPORTING PERIOD: This report summarizes and reviews national data for specific end-points: self-reported asthma prevalence (1980-1994), asthma office visits (1975-1995), asthma emergency room visits (1992-1995), asthma hospitalizations (1979-1994), and asthma deaths (1960-1995). DESCRIPTION OF SYSTEM: The National Center for Health Statistics (NCHS) annually conducts the National Health Interview Survey, which asks about self-reported asthma in a subset of the sample. NCHS collects physician office visit data with the National Ambulatory Medical Care Survey, emergency room visit data with the National Hospital Ambulatory Medical Care Survey, and hospitalization data with the National Hospital Discharge Survey. NCHS also collects mortality data annually from each state and produces computerized files from these data. We used these datasets to determine self-reported asthma prevalence, asthma office visits, asthma emergency room visits, asthma hospitalizations, and asthma deaths nationwide and in four geographic regions of the United States (i.e., Northeast, Midwest, South, and West). RESULTS: We found an increase in self-reported asthma prevalence rates and asthma death rates in recent years both nationally and regionally. Asthma hospitalization rates have increased in some regions and decreased in others. At the state level, only death data are available for asthma; death rates varied substantially among states within the same region. INTERPRETATION: Both asthma prevalence rates and asthma death rates are increasing nationally. Available surveillance information are inadequate for fully assessing asthma trends at the state or local level. Implementation of better state and local surveillance can increase understanding of this disease and contribute to more effective treatment and prevention strategies.

Environmental public health surveillance.

A holistic and collaborative approach needs to be taken in the development of environmental public health surveillance systems. Exposure and hazard surveillance integrated with outcome-based surveillance will blend fragmented strands of data into streams of information. Adequate resources and strong leadership are essential to the creation of such surveillance systems.

Nosocomial outbreak of Candida albicans sternal wound infections following cardiac surgery traced to a scrub nurse.

From August 1988 through October 1989, 15 patients at 1 hospital developed Candida albicans sternal wound infections after cardiac surgery. An investigation found that case-patients were more likely than cardiac surgery patients without sternal wound infections to have surgeries lasting > 165 min (11/15 vs. 20/45; odds ratio [OR], 5.0; 95% confidence interval [CI], 1.5-16.3) or exposure to first scrub nurse A (15/15 vs. 22/45; OR, infinity; 95% CI, 2.5, infinity). Molecular typing of 5 case-patient C. albicans isolates revealed a common strain. Nurse A had a history of recurrent vaginal infections responding to topical antifungal agents; however, cultures of multiple samples from nurse A, beginning 3 weeks after the last infected patient's surgery, failed to yield C. albicans. Following her voluntary transfer from cardiac surgery, no additional infections of case-patients were detected. This study demonstrates the utility of combining epidemiologic methods and molecular typing in investigating C. albicans infection clusters and suggests that a common exogenous source can be responsible for C. albicans surgical wound infections.

Measles epidemic from failure to immunize.

During 1988 through 1990, California experienced its worst measles epidemic in more than a decade, with 16,400 reported cases, 3,390 hospital admissions, and 75 deaths. More than half of the patients were younger than 5 years; the highest incidence was among infants younger than 12 months. The epidemic centered in low-income Hispanic communities in southern and central California. The major cause of the epidemic was low immunization levels among preschool-aged children and young adults. Rates of complications, admission to hospital, and death were surprisingly high. Outbreak control efforts met with indeterminate success. Problems with these efforts included insufficient funding early in the epidemic and disappointing public response to community-based immunization campaigns. The cost of medical care and outbreak control for the epidemic is conservatively estimated at $30.9 million. Unless the level of immunization in preschool-aged children is increased, this type of epidemic will probably recur.