Retrospective validation of a surveillance system for unexplained illness and death: New Haven County, Connecticut.

OBJECTIVES: This study investigated retrospective validation of a prospective surveillance system for unexplained illness and death due to possibly infectious causes. METHODS: A computerized search of hospital discharge data identified patients with potential unexplained illness and death due to possibly infectious causes. Medical records for such patients were reviewed for satisfaction of study criteria. Cases identified retrospectively were combined with prospectively identified cases to form a reference population against which sensitivity could be measured. RESULTS: Retrospective validation was 41% sensitive, whereas prospective surveillance was 73% sensitive. The annual incidence of unexplained illness and death due to possibly infectious causes during 1995 and 1996 in the study county was conservatively estimated to range from 2.7 to 6.2 per 100,000 residents aged 1 to 49 years. CONCLUSIONS: Active prospective surveillance for unexplained illness and death due to possibly infectious causes is more sensitive than retrospective surveillance conducted through a published list of indicator codes. However, retrospective surveillance can be a feasible and much less labor-intensive alternative to active prospective surveillance when the latter is not possible or desired.

Child pedestrian and bicyclist injuries: results of community surveillance and a case-control study.

OBJECTIVES: To describe the dimensions of childhood pedestrian and bicyclist injuries in Long Beach, California, and to identify risk factors for these injuries. POPULATION: Long Beach residents aged 0-14 years who were involved in an auto versus pedestrian or bicyclist incident that resulted in a hospital visit and/or police response, between 1 September 1988 and 31 August 1990. METHODS: Cases were identified retrospectively using hospital charts, police records, and coroner's reports; demographic, clinical, and situational information were abstracted from the same. A nested case-control study was conducted to examine the street environments where children were injured, and to identify environmental risk factors at these case sites. RESULTS: 288 children comprised the sample population. Midblock dart-outs emerged as the single most common type of incident. Most incidents happened on residential streets, but the risk of injury was greatest on larger boulevards, and tended to cluster by region within the city. Adjusted odds ratios show that case sites had a larger proportion of traffic exceeding posted speed limits, and were also four times more likely to be near a convenience store, gas station, or fast food store than control sites. CONCLUSIONS: The findings of this study suggest three possible routes for the prevention of childhood pedestrian and bicyclist injuries: education, law enforcement, and environmental modification.

Risks, costs, and the expected complication of re-injury.

BACKGROUND: The purpose of this study was to determine the characteristics of young victims of violence and the risk of rehospitalization due to intentional injury (recidivism) and to estimate the potential cost of these injuries. MATERIALS AND METHODS: Trauma admissions from January 1, 1991 to December 31, 1993, at San Francisco General Hospital of youths < 25 years old who were victims of gunshot wounds (GSWs), assault, and stab wounds were screened. Five hundred and fifty-two charts were reviewed after sampling every other chart. The cost of hospitalization was estimated from the Medicare charge-to-cost ratio. RESULTS: There were 87 (16%) persons who had a prior injury, of whom 82 (94%) had suffered their injury within the previous 5 years. The predominate mechanism of injury was GSW (242, 44%). There were 38 deaths; 35 (92%) were by firearms. The estimated cost of hospitalization for 552 youths for 3 years was $3,843,545.58. CONCLUSIONS: Intentional injury is a major risk factor and potential predictor for re-injury. Firearms are a major mechanism of intentional injury among youths and a major determinate of death. With the estimated cost of $2,562,363.72 per year for all youths at our hospital, intentional injury is a major health care issue for youths and hospitals.

Ambulance collisions in an urban environment.

INTRODUCTION: Decisions to send an ambulance with or without lights and siren are made every day. While travel with lights and siren is presumed to have relatively more risk associated with it than travel without, little epidemiologic analysis has been conducted to compare the two modes of travel or to characterize collisions in general. OBJECTIVE: To characterize ambulance collisions and assess the risk of traveling with lights and siren in an urban 9-1-1 environment. METHODS: Retrospective analysis of all consecutive ambulance collisions of the Paramedic Division of the San Francisco Department of Public Health during a 27-month period. RESULTS: The overall collision rate for lights and siren (LS) travel was higher than that for non-lights and siren travel, although the difference was not statistically significant (45.9 collisions per 100,000 LS patient travels, 95% confidence limits 29.7, 62.1, versus 27.0/100,000 for non-LS travel, 95% confidence limits 18.3, 35.7). However, the rates of resulting injuries displayed a statistically significant difference (22.2 injuries per 100,000 LS patient travel, 95% confidence limits 11.0, 33.5, versus 1.5/100,000 for non-LS travel, 95% confidence limits -0.6, 3.5). While the majority of collisions (60.0%) occurred during patient-related travel, 35.6% occurred while the ambulance was available awaiting assignment, and 4.4% in a hospital parking lot. The majority of collisions were due to inattention, failure of on-coming traffic to yield, or unsafe parking; unsafe speed was an infrequent cause. Most crashes occurred during daylight, in dry weather, and involved another vehicle. CONCLUSION: There is some elevated risk for collision and added injury during lights and siren travel compared to travel without LS. The causes for these collisions suggest that interventions designed to improve driver skills and increase citizen awareness of an approaching ambulance could help reduce the number of collisions.

Bronchoalveolar lavage in extrinsic allergic alveolitis.

The precise immunopathological mechanism of extrinsic allergic alveolitis explaining the clinical picture as well as the pathological findings is not known. Bronchoalveolar lavage can be a diagnostic help and a method to unravel the pathophysiology of this disease. In the acute stage of extrinsic allergic alveolitis or within 24 h after antigen exposure an increase in the number of neutrophils is seen. After the acute stage, the number of lymphocytes is even higher than in sarcoidosis. In extrinsic allergic alveolitis as well as in sarcoidosis these lymphocytes are mainly T lymphocytes. However, the distribution of OKT 4 and OKT 8 positive lymphocytes was clearly different in both diseases. In sarcoidosis OKT 4 lymphocytes predominate (OKT 4/8 = 7.8) while in extrinsic allergic alveolitis an increase of both OKT 4 and OKT 8 lymphocytes has been found (OKT 4/8 = 1.5). Whether a type III Arthus reaction or a type IV delayed hypersensitivity with an early component is involved, is discussed.