Epidemiology of a large restaurant-associated outbreak of Shiga toxin-producing Escherichia coli O111:NM.

In August 2008, a large outbreak of Shiga toxin-producing Escherichia coli (STEC) O111:NM infections associated with a buffet-style restaurant in rural Oklahoma was identified. A case-control study of restaurant patrons and a retrospective cohort study of catered event attendees were conducted coupled with an environmental investigation to determine the outbreak's source and mode of transmission. Of 1823 persons interviewed, 341 (18·7%) met the outbreak case definition; 70 (20·5%) were hospitalized, 25 (7·3%) developed haemolytic uraemic syndrome, and one died. Multiple food items were significantly associated with illness by both bivariate and multivariate analyses, but none stood out as a predominant transmission vehicle. All water, food, and restaurant surface swabs, and stool cultures from nine ill employees were negative for the presence of Shiga toxin and E. coli O111:NM although epidemiological evidence suggested the outbreak resulted from cross-contamination of restaurant food from food preparation equipment or surfaces, or from an unidentified infected food handler.

Update on hantavirus in Oklahoma: are we missing cases?

Hantavirus Pulmonary Syndrome (HPS) was first recognized in 1993. Through July 6, 2005, 396 cases have been reported in the US, including 50 from Kansas, Texas, and Oklahoma. We report the second case of HPS in Oklahoma and present data from rodent testing to support the presence of hantaviruses across Oklahoma. We examined Oklahoma death certificates for 1999-2003 for possible unreported HPS cases. The rate of death in young adults 15-49 years due to acute respiratory distress syndrome was 69% higher and the death rate due to unspecified respiratory failure was three times higher in the grassland area of Oklahoma as compared to the non-grassland. It appears the highest risk of HPS is in the Oklahoma grasslands but Sin Nombre virus is present in the non-grassland area as well. We request physician collaboration in detection and reporting of HPS cases and present brief recommendations for prevention.

A comparison of two surveillance systems for deaths related to violent injury.

OBJECTIVE: To compare violent injury death reporting by the statewide Medical Examiner and Vital Statistics Office surveillance systems in Oklahoma. METHODS: Using a standard study definition for violent injury death, the sensitivity and predictive value positive (PVP) of the Medical Examiner and Vital Statistics violent injury death reporting systems in Oklahoma in 2001 were evaluated. RESULTS: Altogether 776 violent injury deaths were identified (violent injury death rate: 22.4 per 100 000 population) including 519 (66.9%) suicides, 248 (32.0%) homicides, and nine (1.2%) unintentional firearm deaths. The Medical Examiner system over-reported homicides and the Vital Statistics system under-reported homicides and suicides and over-reported unintentional firearm injury deaths. When compared with the standard, the Medical Examiner and Vital Statistics systems had sensitivities of 99.2% and 90.7% (respectively) and PVPs of 95.0% and 99.1% for homicide, sensitivities of 99.2% and 93.1% and PVPs of 100% and 99.0% for suicide, and sensitivities of 100% and 100% and PVPs of 100% and 31.0% for unintentional firearm deaths. CONCLUSIONS: Both the Vital Statistics and Medical Examiner systems contain valuable data and when combined can work synergistically to provide violent injury death information while also serving as quality control checks for each other. Preventable errors within both systems can be reduced by increasing training, addressing sources of human error, and expanding computer quality assurance programming. A standardized nationwide Medical Examiners' coding system and a national violent death reporting system that merges multiple public health and criminal justice datasets would enhance violent injury surveillance and prevention efforts.

Cost effectiveness analysis of a smoke alarm giveaway program in Oklahoma City, Oklahoma.

OBJECTIVE: To estimate the cost effectiveness of the Lifesavers Residential Fire and Injury Prevention Program (LRFIPP), a smoke alarm giveaway program. SETTING: In 1990, the LRFIPP distributed over 10,000 smoke alarms in an area of Oklahoma City at high risk for residential fire injuries. The program also included fire prevention education and battery replacement components. METHODS: A cost effectiveness analysis was conducted from the societal and health care systems perspectives. The study compared program costs with the total costs of medical treatment and productivity losses averted over a five year period. Fatal and non-fatal residential fire related injuries prevented were estimated from surveillance data. Medical costs were obtained from chart reviews of patients with fire related injuries that occurred during the pre-intervention period. RESULTS: During the five years post-intervention, it is estimated that the LRFIPP prevented 20 fatal and 24 non-fatal injuries. From the societal perspective, the total discounted cost of the program was $531,000. Total discounted net savings exceeded $15 million. From the health care system perspective, the total discounted net savings were almost $1 million and would have a net saving even if program effectiveness was reduced by 64%. CONCLUSIONS: The program was effective in reducing fatal and non-fatal residential fire related injuries and was cost saving. Similar programs in other high risk areas would be good investments even if program effectiveness was lower than that achieved by the LRFIPP.

Evaluating injury prevention programs: the Oklahoma City Smoke Alarm Project.

Evaluation of injury prevention programs is critical for measuring program effects on reducing injury-related morbidity and mortality or on increasing the adoption of safety practices. During the planning and implementation of injury prevention programs, evaluation data also can be used to test program strategies and to measure the program's penetration among the target population. The availability of this early data enables program managers to refine a program, increasing the likelihood of successful outcomes. The Oklahoma City Smoke Alarm Project illustrates how an evaluation was designed to inform program decisions by providing methodologically sound data on program processes and outcomes. This community intervention trial was instituted to reduce residential fire-related injuries and deaths in a geographic area of Oklahoma City that was disproportionately affected by this problem. The distribution of free smoke alarms in targeted neighborhoods was accompanied by written educational pamphlets and home-based follow-up to test whether the alarms were functioning correctly. Early evaluation during the planning and implementation phases of the program allowed for midcourse corrections that increased the program's impact on desired outcomes. During the six years following the project, the residential fire-related injury rate decreased 81% in the target population but only 7% in the rest of Oklahoma City. This dramatic decline in fire-related injuries in the target area is largely attributed to the free smoke alarm distribution as well as to educational efforts promoting awareness about residential fires and their prevention.

Ocular injuries sustained by survivors of the Oklahoma City bombing.

OBJECTIVE: The purpose of this study is to provide a review of the ocular injuries sustained by survivors of the April 19, 1995, bombing of the Alfred P. Murrah Federal Building in Oklahoma City. DESIGN: Retrospective, noncomparative case series. PARTICIPANTS: The authors retrospectively evaluated data collected on all surviving persons receiving ocular injuries during the bombing and on all at-risk occupants of the federal building and four adjacent buildings. METHODS: Injury data from survivors were collected from multiple sources to include hospital medical records, a physician survey, emergency medical services run reports, written survivor accounts, building occupant survey, telephone interviews, and mail surveys. MAIN OUTCOME MEASURES: The types of ocular injuries, the associated systemic injuries, and the location of the injured at the time of the blast were evaluated. RESULTS: Fifty-five (8%) of the 684 injured bombing survivors sustained an ocular injury. Persons injured in the Murrah building were more than three times more likely to sustain an ocular injury than other injured persons. Seventy-one percent of ocular injuries occurred within 300 feet of the point of detonation. The most common serious ocular injuries included lid/brow lacerations (20 patients, 23 eyes), open globe injuries (12 eyes), orbital fractures (6 eyes), and retinal detachment (5 eyes). A retained intraocular foreign body accounted for only two of the injuries (4%). Glass accounted for nearly two thirds of the ocular injuries. CONCLUSIONS: Blasts involving explosions inflict severe ocular injury, mostly as a result of secondary blast effects from glass, debris, etc. Eye injuries in bombings can probably be prevented by increasing the distance from and orientation away from windows (i.e., by facing desks away from windows). Use of such products as laminated glass, toughened window glazing, and Mylar curtains may reduce glass projectiles in the blast vicinity.

Psychiatric disorders among survivors of the Oklahoma City bombing.

CONTEXT: Disasters expose unselected populations to traumatic events and can be used to study the mental health effects. The Oklahoma City, Okla, bombing is particularly significant for the study of mental health sequelae of trauma because its extreme magnitude and scope have been predicted to render profound psychiatric effects on survivors. OBJECTIVE: To measure the psychiatric impact of the bombing of the Alfred P. Murrah Federal Building in Oklahoma City on survivors of the direct blast, specifically examining rates of posttraumatic stress disorder (PTSD), diagnostic comorbidity, functional impairment, and predictors of postdisaster psychopathology. DESIGN, SETTING, AND PARTICIPANTS: Of 255 eligible adult survivors selected from a confidential registry, 182 (71%) were assessed systematically by interviews approximately 6 months after the disaster, between August and December 1995. MAIN OUTCOME MEASURES: Diagnosis of 8 psychiatric disorders, demographic data, level of functioning, treatment, exposure to the event, involvement of family and friends, and physical injuries, as ascertained by the Diagnostic Interview Schedule/Disaster Supplement. RESULTS: Forty-five percent of the subjects had a postdisaster psychiatric disorder and 34.3% had PTSD. Predictors included disaster exposure, female sex (for any postdisaster diagnosis, 55% vs 34% for men; chi2 = 8.27; P=.004), and predisaster psychiatric disorder (for PTSD, 45% vs 26% for those without predisaster disorder; chi2 = 6.86; P=.009). Onset of PTSD was swift, with 76% reporting same-day onset. The relatively uncommon avoidance and numbing symptoms virtually dictated the diagnosis of PTSD (94% meeting avoidance and numbing criteria had full PTSD diagnosis) and were further associated with psychiatric comorbidity, functional impairment, and treatment received. Intrusive reexperience and hyperarousal symptoms were nearly universal, but by themselves were generally unassociated with other psychopathology or impairment in functioning. CONCLUSIONS: Our data suggest that a focus on avoidance and numbing symptoms could have provided an effective screening procedure for PTSD and could have identified most psychiatric cases early in the acute postdisaster period. Psychiatric comorbidity further identified those with functional disability and treatment need. The nearly universal yet distressing intrusive reexperience and hyperarousal symptoms in the majority of nonpsychiatrically ill persons may be addressed by nonmedical interventions of reassurance and support.

Estimating the proportion of homes with functioning smoke alarms: a comparison of telephone survey and household survey results.

OBJECTIVES: This study determined the proportion of homes with functioning smoke alarms in a low-income area experiencing a high rate of residential fire-related injuries. METHODS: An on-site survey of households was conducted to confirm the results of a telephone survey. RESULTS: In the telephone survey, 71% of households reported having functioning smoke alarms. In the household survey, 66% of households reported having functioning alarms; however, when the alarms were tested, the percentage dropped to 49%. CONCLUSIONS: Telephone surveys may overestimate the presence of functioning smoke alarms in some populations. Thus, the use of telephone surveys to establish baseline measures could significantly affect the evaluation of smoke-alarm giveaway programs.

A prospective study of long-term health outcomes among Oklahoma City bombing survivors.

A follow-up study was conducted to identify long-term physical and emotional outcomes among Oklahoma City bombing survivors. Baseline data were gathered by the Oklahoma State Department of Health in 1995. Follow-up data were gathered by telephone interviews of survivors from 1-1/2 to 3 years after the bombing. The frequency of medical diagnoses, symptoms, medical cost, physical and social life changes, and services utilized since the bombing were assessed. A total of 494 persons were interviewed, 92 percent had been physically injured in the bombing. Seventy-nine percent of persons interviewed rated their general health status as "good," "very good," or "excellent." Overall, one-fourth to one-third of survivors reported being newly diagnosed with audiologic changes, anxiety, and depression since the bombing. One-third of persons reported preexisting medical conditions that had worsened since the bombing including depression (26%) and asthma/bronchitis (22%). The most frequently reported posttraumatic stress disorder symptoms were "being jumpy or easily startled" and "recurring distressful thoughts of the bombing." The most frequently utilized medical services were psychological counseling (63%) and audiology services (48%). Total costs were estimated of $ 5.7 million. Overall, persons who had been hospitalized with bombing injuries reported higher rates of diagnoses, symptoms, and services utilization. These findings suggest that a large proportion of survivors of a terrorist bombing, especially those seriously injured, will experience long-term physical and/or emotional outcomes and increased need for treatment for bombing-related medical conditions. All survivors should be carefully assessed over time for auditory damage, depression, anxiety, and posttraumatic stress disorder.

Oklahoma Firearm-Related Injury Surveillance.

CONTEXT: The magnitude of firearm-related deaths is known, but few studies have evaluated the magnitude and epidemiology of nonfatal firearm-related injuries. The circumstances resulting in fatal versus nonfatal injury are likely very different. No single data source provides complete details on nonfatal shootings. OBJECTIVE: To establish a surveillance system to define the epidemiology of fatal and nonfatal firearm-related injuries. DESIGN: Data were collected on fatal and nonfatal firearm-related injuries that occurred in 1995. SETTING: State of Oklahoma. PARTICIPANTS: Medical Examiner, Vital Statistics, hospital emergency and medical records departments, police departments, newspaper clipping service. MAIN OUTCOME MEASURES: Incidence rate of firearm-related injuries; case-fatality rate; demographic, medical, and epidemiologic data; sensitivity of each reporting source; completeness of reporting. RESULTS: The incidence rate of firearm-related injuries was 45.5 per 100,000 population. The case fatality rate was 35%. Injury rates were highest among adolescents, young adults, males, and African Americans. The Medical Examiner and Vital Statistics reported 87% and 98% of fatal cases, respectively. Passive surveillance of hospital emergency departments identified 72% of patients seeking hospital treatment. Among inpatients, 81% were identified by medical records departments. Newspaper clippings were obtained for 31% of cases. Information on the victim-perpetrator relationship and the type of firearm was available for 79% and 80% of cases, respectively. CONCLUSIONS: Statewide surveillance of firearm-related injuries using multiple data sources is possible and provides a picture of the overall firearm-related injury problem. Strategies to enhance computer linkages of medical and police data should be pursued to maximize the sensitivity of reporting and minimize the costs of surveillance.

Evaluation of three smoke detector promotion programs.

CONTEXT: Seventy percent of U.S. residential fire deaths occur in homes without a working smoke detector. To help prevent residential fire deaths, many programs have distributed or installed detectors in unprotected homes. Because persons receiving a detector may not install it and because detector batteries require annual replacement, the enduring effectiveness of these programs may be questioned. OBJECTIVE: We evaluated the long-term functional status of smoke detectors distributed to high-risk households in eight areas of Minnesota, Cherokee County (North Carolina), and Oklahoma City (Oklahoma). DESIGN: Cross-sectional. SETTING: Home visits were made to check the detectors that were distributed 3 to 4 years earlier. PARTICIPANTS: Randomly selected households from the three detector promotion programs. MAIN OUT-COME MEASURE: At least one working smoke detector. RESULTS: Participation rates ranged from 72% to 82%. The percentage of evaluation households with at least one working detector ranged from 58% in Oklahoma to 73% in North Carolina. In 76% of households with nonworking detectors, the batteries were either missing or disconnected. When batteries in nonworking detectors were replaced, 83% of the detectors regained function. CONCLUSIONS: Future programs should consider distributing detectors that do not require annual battery changes or find effective ways to ensure that batteries are routinely replaced. Programs should also provide each household with the number of detectors needed to meet the most current recommended standard of the National Fire Protection Agency. The evaluation's participation rates support the practicality of unannounced home visits to evaluate home injury prevention programs in high-risk groups.

Comparison of community based smoke detector distribution methods in an urban community.

OBJECTIVES: Various methods of soliciting participation for a large smoke detector giveaway program were tested to determine the most effective method of distributing smoke detectors to a high risk urban population. SETTING: The target area was a 24 square mile (62 km2) section on the south side of Oklahoma City where 16% (73,301) of the city's population resided in 16% (34,845) of the dwellings (excluding apartments). Of the 66 persons in Oklahoma City who were injured in residential fires from September 1987 to April 1990, 45% (30) were in the target area. Of the target area injuries, 47% resulted from fires started by children playing with fire (fireplay). METHODS: The number of homes without detectors was estimated by telephone survey. Four different methods of soliciting participants were used, including notifying residents by mail; placing flyers on the doors of every habitable residence; and displaying flyers at public places (grocery stores, convenience stores, restaurants, etc). Each of these methods alerted residents that free smoke detectors were available at specific fire stations. The fourth method was distributing detectors door-to-door (canvassing). RESULTS: The canvassing method resulted in significantly more smoke detectors being distributed to homes without detectors (107%) than any of the three other methods (18%) (p < 0.00001). The canvassing method distributed detectors to 31% of the total target homes, compared with 5% with the other methods (p < 0.00001). Canvassing also resulted in the lowest estimated cost per detector distributed ($1.96) (all other methods, $3.95), and in the largest number distributed per volunteer hour (5.9 v 3.1 detectors per hour by other methods). CONCLUSIONS: Distributing smoke detectors directly to homes (canvassing) was the most effective and cost efficient method to reach high risk urban residents.

Injuries and illnesses in working dogs used during the disaster response after the bombing in Oklahoma City.

OBJECTIVES: To determine characteristics of working dogs used during the disaster response after the bombing in Oklahoma City and risk factors for injuries and illnesses of those dogs, and to document recommendations for future disaster responses. DESIGN: Survey. STUDY POPULATION: Information for 74 working dogs used at the bombing site. PROCEDURES: Dog handlers were identified and asked to complete a questionnaire. Questions were asked about the training and use of each dog, use of paw protection, injuries and illnesses incurred, possible effects after completion of duty at Oklahoma City, and handler's experience. RESULTS: Data were obtained for all 74 dogs used at the site. Handlers of 69 of 74 (93%) dogs responded. The dogs had been extensively trained and were used 491 dog-days at the site, with 46 dogs used in search, 14 in patrol, 12 in explosive-detection duty, and 2 in search/patrol. Fifteen (22%) dogs became ill. Nineteen (28%) dogs incurred 20 injuries. Footpad injuries constituted 18 of the injuries. Only 16 of 69 (23%) dogs were provided with paw protection. Dogs were more likely to be injured when they were used in a search capacity, were used during the first 2 days after the bombing, were German Shepherd Dogs, or were older. CLINICAL IMPLICATIONS: Although working in a high-risk environment, injuries to dogs were few, and most were minor. Specific recommendations could facilitate use of dogs in disaster situations and improve safety for those dogs.

Injuries to rescue workers following the Oklahoma City bombing.

The objective of this study was to identify and describe physical injuries to rescue workers in the aftermath of the Oklahoma City bombing. Data were obtained from medical records from 16 hospital emergency departments and specialty clinics in the Oklahoma City area, and reported visits to medical providers at the bombing site. Participants were rescue personnel from the Oklahoma City Fire Department, the mutual aid fire stations in the Oklahoma City area, the Federal Emergency Management Agency's Urban Search and Rescue teams, and military personnel stationed near Oklahoma City. All participants were involved in the rescue and recovery operation. The two main outcome measures were (1) the number, types, and rates of injuries; and (2) comparisons of case-finding methods, including medical chart review and telephone interview. The most common injuries were strains and sprains (21.4%), foreign bodies in eyes (14.5%), and laceration/crush/puncture wounds (18.4%). Of the four case-finding mechanisms, telephone interviews following the event identified the largest number of cases (84.5%). Most injuries were minor; some injuries such as chemical burns were preventable. The potential utility of other data collection mechanisms is considered.

The EMS response to the Oklahoma City bombing.

This is a descriptive study of the Emergency Medical Services response to a bombing of a United States Federal Building in Oklahoma City, Oklahoma on 19 April 1995. The explosion emanated from a rented truck parked in the front of the building. The force of the explosion destroyed three of the four support columns in the front of the building and resulted in a pancaking effect of the upper floors onto the lower floors. There were three distinct phases of the medical response: 1) Immediately available local EMS ambulances and staff; 2) Additional ambulances staffed by recalled, off-duty personnel; and 3) mutual-aid ambulances and personnel from the surrounding communities. There were 361 persons in the building at the time of the explosion, 163 of these perished. Within the first hour of the explosion, 139 patients were transported to area hospitals. Of these, 32% were in critical condition. During the day of the explosion, 444 persons were treated for physical injuries: 410 of these were related to the explosion and 14, including one with fatal injuries, were sustained during search and rescue attempts. A total of 354 (80%) were treated and released from emergency departments, and 90 (20%) were admitted to hospitals. Six of the transported victims either were dead on arrival to the emergency department or died after admission to the hospital. Of those who died, 95% of the deaths were related to blunt trauma associated with the collapse of the structure. Only three persons were extricated alive after the first five hours following the explosion. The scene became flooded with volunteers who, although their intentions were to provide help and aid to those injured, created a substantial logistical problem for Incident Command. Several other lessons were learned: 1) Telephone lines and cells became overloaded, but the Hospital Emergency Administrative Radio system was operational only in three of the 15 hospitals; 2) Volunteer personnel should have responded to the hospitals and not to the scene; and 3) Training was an essential for the success of such a response. Thus, the success of this operation was a function of the intense training, practice, and coordination between multiple agencies.