Emerging infectious diseases: public health issues for the 21st century.

Infectious diseases are the third leading cause of death in the United States and the leading cause worldwide. As the new millennium approaches, the public health community must replenish capacity depleted during years of inadequate funding while simultaneously incorporating new technologies and planning for the longer term. Among the challenges facing the public health community is the need for coordinated, global, multisectoral approaches to preventing and controlling complex infectious disease problems.

Dog bites: still a problem?

OBJECTIVE: To estimate the incidence of dog bites in the USA and compare it with similar estimates from 1994. DESIGN: Nationally representative cross-sectional, list-assisted, random-digit-dialed telephone survey conducted during 2001-2003. METHODS: Weighted estimates were generated from data collected by surveying 9684 households during 2001-2003 and compared with results from a similar survey conducted in 1994. Estimates for persons aged 15-17 years were extrapolated on the basis of rates for 10-14-year-olds. RESULTS: Whereas the incidence of dog bites among adults remained relatively unchanged, there was a significant (47%) decline in the incidence of dog bites among children compared with that observed in the 1994 survey, particularly among boys and among those aged 0-4 years. Between 2001 and 2003, an estimated 4 521 300 persons were bitten each year. Of these, 885 000 required medical attention (19%). Children were more likely than adults to receive medical attention for a dog bite. Among adults, bite rates decreased with increasing age. Among children and adults, having a dog in the household was associated with a significantly increased incidence of dog bites, with increasing incidence also related to increasing numbers of dogs. CONCLUSIONS: Dog bites continue to be a public health problem affecting 1.5% of the US population annually. Although comparison with similar data from 1994 suggests that bite rates for children are decreasing, there still appears to be a need for effective prevention programs.

Pediatric head injuries and deaths from bicycling in the United States.

OBJECTIVE: To estimate the potential benefit of increasing bicycle helmet use among children and adolescents in the United States. DESIGN: All bicycle-related deaths (Multiple Cause-of-Death Public Use Data Tapes, 1989 through 1992) and bicycle-related injuries treated in sampled emergency departments (National Electronic Injury Surveillance System, 1989 through 1993) were used to calculate traumatic brain injury-associated death and head injury rates per 1,000,000 US residents. Preventable injuries and deaths were estimated by calculating the population-attributable risk of head injury due to nonuse of bicycle helmets. PATIENTS: US residents aged 0 through 19 years who were injured or who died as a result of a bicycle crash. RESULTS: An average of 247 traumatic brain injury deaths and 140,000 head injuries among children and adolescents younger than 20 years were related to bicycle crashes each year in the United States. As many as 184 deaths and 116,000 head injuries might have been prevented annually if these riders had worn helmets. An additional 19,000 mouth and chin injuries were treated each year. The youngest age groups had the highest proportions of both head and mouth injuries. CONCLUSION: There continues to be a need to advocate for greater use of bicycle helmets, particularly among young children. Helmet design changes should be considered to prevent mouth injuries.

Fatal dog attacks, 1989-1994.

OBJECTIVES: To update data on fatal dog bites and see if past trends have continued. DESIGN: To merge data from vital records, the Humane Society of the United States, and searches of electronic news files. SETTING: United States. SUBJECTS: U.S. residents dying in the U.S. from 1989 through 1994 from dog bites. RESULTS: We identified 109 dog bite-related fatalities, of which 57% were less than 10 years of age. The death rate for neonates was two orders of magnitude higher than for adults and the rate for children one order of magnitude higher. Of classifiable deaths, 22% involved an unrestrained dog off the owner's property, 18% involved a restrained dog on the owner's property, and 59% involved an unrestrained dog on the owner's property. Eleven attacks involved a sleeping infant; 19 dogs involved in fatal attacks had a prior history of aggression; and 19 of 20 classifiable deaths involved an unneutered dog. Pit bulls, the most commonly reported breed, were involved in 24 deaths; the next most commonly reported breeds were rottweilers (16) and German shepherds (10). CONCLUSIONS: The dog bite problem should be reconceptualized as a largely preventable epidemic. Breed-specific approaches to the control of dog bites do not address the issue that many breeds are involved in the problem and that most of the factors contributing to dog bites are related to the level of responsibility exercised by dog owners. To prevent dog bite-related deaths and injuries, we recommend public education about responsible dog ownership and dog bite prevention, stronger animal control laws, better resources for enforcement of these laws, and better reporting of bites. Anticipatory guidance by pediatric health care providers should address dog bite prevention.

Which dogs bite? A case-control study of risk factors.

OBJECTIVE: Dog bites cause an estimated 585,000 injuries resulting in the need for medical attention yearly and children are the most frequent victims. This study sought to determine dog-specific factors independently associated with a dog biting a nonhousehold member. METHODS: A matched case-control design comprising 178 pairs of dogs was used. Cases were selected from dogs reported to Denver Animal Control in 1991 for a first-bite episode of a nonhousehold member in which the victim received medical treatment. Controls were neighborhood-matched dogs with no history of biting a nonhousehold member, selected by modified random-digit dialing based on the first five digits of the case dog owner's phone number. Case and control dog owners were interviewed by telephone. RESULTS: Children aged 12 years and younger were the victims in 51% of cases. Compared with controls, biting dogs were more likely to be German Shepherd (adjusted odds ratio (ORa) = 16.4, 95% confidence interval (CI) 3.8 to 71.4) or Chow Chow (ORa = 4.0, 95% CI 1.2 to 13.7) predominant breeds, male (ORa = 6.2, 95% CI 2.5 to 15.1), unneutered (ORa = 2.6, 95% CI 1.1 to 6.3), residing in a house with > or = 1 children (ORa = 3.5, 95% CI 1.6 to 7.5), and chained while in the yard (ORa = 2.8, 95% CI 1.0 to 8.1). CONCLUSIONS: Pediatricians should advise parents that failure to neuter a dog and selection of male dogs and certain breeds such as German Shepherd and Chow Chow may increase the risk of their dog biting a nonhousehold member, who often may be a child. The potential preventability of this frequent public health problem deserves further attention.

Smoking policies of licensed child day-care centers in the United States.

The authors analyzed data from a national survey of 2003 directors of licensed child day-care centers to determine employee smoking policies, measure compliance with state and local employee smoking regulations for child day-care centers and state clean indoor air laws, and to estimate the extent of exposure to environmental tobacco smoke in these settings. Forty states regulated employee smoking in child day-care centers, but only three states required day-care centers to be smoke-free indoors. More than 99% of licensed child day-care centers had employee smoking policies that complied with the appropriate state or local smoking regulations. Nearly 55% of centers were smoke-free indoors and outdoors, and 26% were smoke-free indoors only. The best predictors of more stringent employee smoking policies were location in the West or South, smaller size, independent ownership, or having written smoking policies. Despite the presence of strong smoking policies at the majority of licensed child day-care centers, more than 752,000 children in the United States are at risk for environmental tobacco smoke exposure in these settings. Health care professionals and parents should insist that child day-care centers be smoke-free indoors and, preferably, smoke-free indoors and outdoors.

A nationwide study of the risk of injury associated with day care center attendance.

OBJECTIVE: Because an increasing proportion of US children spends time in day care center environments, a national estimate of injury risks in day care centers is needed. METHODS: We interviewed directors of 1797 day care centers from every state and the District of Columbia from October to December 1990 and analyzed medically attended injuries and center characteristics reported by the directors. RESULTS: The centers were attended by 138,404 children. In the 2 months before the center directors were interviewed, 556 children sustained injuries requiring medical attention while attending the centers. The injury rate was 1.5 injuries per 100,000 child hours in day care. The most common injuries were cuts or lacerations (31%), bumps or bruises (15%), fractures (10%), and dental injuries (8%). Most injuries (51%) occurred on the playground. Many injuries (18%), and more than half of fractures and concussions (53%) were due to falls from climbing equipment. CONCLUSIONS: Day care center injury rates estimated by this study were relatively low. Many injuries that occur in this setting are probably minor. However, lowering the height of playground equipment and providing more resilient playground surfaces could further reduce injury risks in day care centers.

Estimates of fatal child abuse and neglect, United States, 1979 through 1988.

The results of recent surveys in the United States have suggested a rising tide of fatalities due to child abuse or neglect (CAN). Because these surveys lack consistency in case definition and are incomplete in coverage, the use of death certificate data to estimate the number of CAN deaths was explored. To estimate these deaths among children 0 through 17 years old for 1979 through 1988, three models were formulated, each comprising six coding categories: (1) deaths coded explicitly as due to CAN, (2) homicides, (3) injury deaths of undetermined intentionality, (4) accidental injury deaths, (5) sudden infant death syndrome fatalities, and (6) natural-cause deaths. Research studies and crime data were relied on to estimate the proportions of deaths in categories 2 through 6 that were actually due to CAN, and other assumptions were varied to create a range of estimates. For the 10-year period, the estimated mean annual CAN fatalities ranged from 861 to 1814 for ages 0 through 4, and from 949 to 2022 for ages 0 through 17. Child abuse and neglect death rates did not increase over the period; in fact, they were relatively stable for ages 0 through 17 and showed a modest decline for 0 through 4. Ninety percent of fatal CAN occurs among children younger than 5 years old, and 41% occurs among infants. About 85% of CAN deaths are recorded as due to other causes.(ABSTRACT TRUNCATED AT 250 WORDS)

Bicycle helmet use among Maryland children: effect of legislation and education.

Although bicycle helmets are effective in preventing head injuries, use of helmets among children remains infrequent. In response to the bicycling deaths of two children, Howard County, Maryland, became the first US jurisdiction to mandate use of bicycle helmets for children. Schoolchildren were lectured by police about the law before its enactment. Prelaw and postlaw helmet use was observed in Howard County and two control counties: Montgomery (which sponsored a community education program) and Baltimore County (no helmet activities). Prelaw crude helmet use rates for children were 4% (95% confidence interval [CI] 0% to 10%) for Howard, 8% (95% CI 3% to 13%) for Montgomery, and 19% (95% CI 5% to 33%) for Baltimore. Postlaw rates were 47% (95% CI 32% to 62%), 19% (95% CI 11% to 27%), and 4% (95% CI 0 to 11%), respectively. The rate of bicycle helmet use by Howard County children is now the highest documented for US children. A similar increase in helmet use among children younger than 16 years nationwide could prevent about 100 deaths and 56,000 emergency-department-treated head injuries annually. Physicians and other health professionals should consider proposing and supporting the Howard County approach in their communities.

Deaths from residential fires among older people, United States, 1984.

Deaths from fires are the fifth leading cause of injury death among people aged 65 years or older. To describe the epidemiology of deaths from residential fires among older people, we analyzed mortality data for 1984 collected by the National Center for Health Statistics. Although older people represented only 12% of the U.S. population in 1984, they accounted for 29% (1,278) of that year's 4,466 residential fire deaths. Conflagrations accounted for 78% of older people's deaths from residential fires; clothing ignitions and other fires accounted for 11% each. Residential fire death rates increased with advancing age. Older black people had death rates 4.6 times the death rates of older white people. Older males had higher death rates than older females. Host, environmental, and behavioral risk factors for residential fire deaths among older people and potential strategies for intervention are discussed. Unless intervention strategies are focused on older people, the residential fire death toll in the U.S. may actually grow as the population of older people increases from 12% of the population in 1984 to about 21% of the population in 2030.

Evaluation of a statewide bicycle helmet law via multiple measures of helmet use.

OBJECTIVES: To evaluate an Oregon law requiring bicyclists younger than 16 year to wear a helmet and to compare methods of measuring helmet use. DESIGN: Four prelaw and postlaw statewide helmet use surveys: (1) statewide observations, (2) middle school observations, (3) classroom self-report surveys, and (4) a statewide adult telephone survey. SETTING: Oregon. SUBJECTS: Statewide observations, 3313 child bicyclists at 13 sites; middle school observations, 995 child bicyclists at 33 randomly selected middle schools; classroom self-report surveys, fourth, sixth, and eighth graders in 448 classrooms (ie, 8955 students) before the law was effected and 456 classrooms (ie, 9811 students) after the law was effected in 66 randomly selected schools; and statewide telephone survey, 1219 randomly called parents of 1437 children younger than 16 years. MAIN OUTCOME MEASURES: Prelaw and postlaw helmet use and ownership and knowledge and opinion about the law. RESULTS: Observed helmet use among youth was 24.5% before the law was effected and 49.3% after the law was effected. School-observed use increased from 20.4% to 56.1%. Classroom survey self-reported "always" use of helmets increased from 14.7% to 39.4%; reported use on the day of the survey increased from 25.8% to 76.0%. Telephone survey-reported "always" helmet use increased from 36.8% to 65.7%. Younger children and girls were more likely to use helmets. Most students (ie, 87.8%) and parents (ie, 95.4%) knew about the law; however, only 42.6% of children thought the law was a good idea. CONCLUSIONS: We conclude that (1) the law increased helmet use; (2) although use estimates differ, all helmet surveys showed similar degrees of prelaw and postlaw change; and (3) half of child bicyclists are still not wearing helmets, indicating a need for additional promotion of helmet wearing. Laws seem to be an effective way to increase helmet use.

Injuries from falls on playgrounds. Effects of day care center regulation and enforcement.

OBJECTIVES: To measure the incidence of playground fall injuries among children attending licensed US day care centers and to evaluate how injury incidence varies with center characteristics and with the regulatory and enforcement climate in which centers operate. DESIGN: Telephone surveys of directors of day care centers and enforcement agencies and review of written day care regulations. SETTING: Probability sample of licensed day care centers in 50 states and the District of Columbia. PARTICIPANTS: Children attending day care centers with playgrounds. MAIN OUTCOME MEASURES: Medically attended playground fall injuries. RESULTS: Among the 1740 day care centers studied, a weighted total of 89.2 injuries occurred during the 2-month study period (0.25/100,000 child-hours in day care). The most important risk factor for injury was height of the tallest piece of climbing equipment on the playground in both bivariate (P = .01) and multivariate (P = .02) analyses. Neither regulations addressing playground safety or playground surfaces nor enforcement patterns were associated with lower injury rates. CONCLUSIONS: Additional effort is needed to develop and evaluate regulations and enforcement that reduce injury risks for children while minimizing burden on day care centers. In the meantime, limiting climbing equipment heights may reduce playground injury rates.

Effect of a state law on reported bicycle helmet ownership and use.

OBJECTIVE: To evaluate the effect of a state law on reported bicycle helmet ownership and use. DESIGN: Multistage cluster random-digit-dialing telephone survey. SETTING: Georgia, June through November 1993. PARTICIPANTS: Adults who reported the behavior of bicyclists 4 through 15 years old. INTERVENTION: State law mandating helmet use after July 1, 1993, for all bicyclists aged younger than 16 years. MAIN OUTCOME MEASURES: Bicycle helmet ownership and use. RESULTS: Reported helmet ownership increased from 39% before the law took effect to 57% afterward (+ 46%, P = .06). Reported use increased from 33% before to 52% afterward (+ 58%, P < .05). About 7% of riders changed from "never-wearing" to "always-wearing" behavior. After the law took effect, in those households in which the law was known, 69% of riders owned and 64% used a helmet. By comparison, in those households in which the law was not known, only 30% owned and 25% used a helmet (P < .01). Reported ownership and use were 93% concordant, inversely related to rider age, and directly related to household income. Multivariable analysis indicated that race was an effect modifier of reported helmet ownership and use. In black riders, knowledge of the law appeared to be highly associated with both reported helmet ownership and use but was not significant in white riders. In white riders, though age and income were significantly associated with reported helmet ownership and use. CONCLUSIONS: This law appeared important in increasing reported helmet ownership and use, particularly in black riders. Since knowledge of the law was associated with increased ownership and use, additional publicity about the law might further increase helmet use. Because most riders who owned helmets used them, give-away programs targeting areas of low ownership may also increase use.

Geographic patterns of fatal abuse or neglect in children younger than 5 years old, United States, 1979 to 1988.

OBJECTIVE: To examine geographic patterns of fatal child abuse or neglect (CAN) among children younger than 5 years old. DESIGN: A death certificate-based model to estimate the occurrence of fatal CAN. SETTING: United States, 1979 to 1988. PARTICIPANTS: The population of children younger than 5 years old. INTERVENTIONS: None. MAIN RESULTS: We estimate that from 868 to 1815 deaths annually occur among children younger than 5 years old from CAN. The lower figure is the estimate of confirmed CAN, and the higher is the estimate of the sum of confirmed, probable, and possible CAN. Death rates were highest in the South and West, intermediate in the North Central, and lowest in the Northeast. A threefold difference was noted between rates in the lowest- and highest-ranking states (ie, Connecticut, 2.9 to 5.2 per 100,000, and Nevada, 6.7 to 15.4 per 100,000, respectively). When the 39 largest metropolitan areas were ranked, a similar variation between the lowest and the highest was observed (ie, Boston, Mass, 2.7 to 5.5 per 100,000, and Phoenix, Ariz, 6.6 to 15.5 per 100,000, respectively). CONCLUSION: Understanding the sizable geographic variation in CAN deaths rates could lead to effective interventions. If the US fatality rate were reduced to that of Connecticut, between 434 and 908 fewer CAN deaths might occur annually.

Injury prevention practices as depicted in G-rated and PG-rated movies.

BACKGROUND: Previous studies on alcohol, tobacco, and violence suggest that children's behavior can be influenced by mass media; however, little is known about the effect of media on unintentional injuries, the leading cause of death among young persons in the United States. OBJECTIVE: To determine how injury prevention practices are depicted in G-rated (general audience) and PG-rated (parental guidance recommended) movies. DESIGN: Observational study. SETTING: The 25 movies with the highest domestic box-office grosses and a rating of G or PG for each year from 1995 through 1997. Movies that were predominantly animated or not set in the present day were excluded from analysis. SUBJECTS: Movie characters with speaking roles. MAIN OUTCOME MEASURES: Safety belt use by motor vehicle occupants, use of a crosswalk and looking both ways by pedestrians crossing a street, helmet use by bicyclists, personal flotation device use by boaters, and selected other injury prevention practices. RESULTS: Fifty nonanimated movies set in the present day were included in the study. A total of 753 person-scenes involving riding in a motor vehicle, crossing the street, bicycling, and boating were shown (median, 13.5 person-scenes per movie). Forty-two person-scenes (6%) involved falls or crashes, which resulted in 4 injuries and 2 deaths. Overall, 119 (27%) of 447 motor vehicle occupants wore safety belts, 20 (18%) of 109 pedestrians looked both ways before crossing the street and 25 (16%) of 160 used a crosswalk, 4 (6%) of 64 bicyclists wore helmets, and 14 (17%) of 82 boaters wore personal flotation devices. CONCLUSIONS: In scenes depicting everyday life in popular movies likely to be seen by children, characters were infrequently portrayed practicing recommended safe behaviors. The consequences of unsafe behaviors were rarely shown. The entertainment industry should improve its depiction of injury prevention practices in G-rated and PG-rated movies.

Cluster of abortion deaths at a single facility.

This report describes a cluster of four abortion-related deaths at a single facility from 1979 to 1983. The deaths followed curettage abortions at eight to 18 weeks' gestation. One death was attributed to a prolapsed mitral valve, and one was attributed to spontaneous ventricular fibrillation. Two deaths, which occurred within three weeks of each other, were caused by hemorrhage from uterine perforation. The person who allegedly performed the last two abortions was not licensed to practice medicine, nor was he under the supervision of a licensed physician. The estimated death-to-case rate at this facility (57 per 100,000 abortions) is significantly higher than the national rate (1.2 per 100,000 abortions, P less than .001). To prevent such situations, prompt treatment of abortion complications and community-based surveillance of serious morbidity should be performed.

A comparison of driver- and passenger-based estimates of alcohol-impaired driving.

INTRODUCTION: Persons who drive after drinking or ride with drinking drivers are at increased risk of motor vehicle crash. Although alcohol is involved in 40% of fatal motor vehicle crashes yearly, there exist few systems to monitor alcohol-impaired driving. In this study we compare driver- and passenger-based estimates of the prevalence of alcohol-impaired driving. DESIGN: A random-digit-dialing telephone survey of the United States. Participants were adults aged 18 or older who were English- or Spanish-speaking from 5238 households (response rate = 56.1%). RESULTS: From the 4603 respondents who reported driving in the preceding 30 days, we estimate that there were 126 million drinking-driving episodes in the United States in 1994. From the 4380 passengers in the preceding 30 days, we estimate 191 million episodes. Three percent of respondents self-reported as drinking drivers (4.8% of males and 1.3% of females) and 4.9% as passengers of drinking drivers. Drinking drivers were more likely to be passengers of drinking drivers (44% versus 4% of nondrinking drivers). Drinking drivers were also more than twice as likely to report drinking daily, and only one half as likely to report always wearing their safety belts. CONCLUSION: Passengers who report riding with a drinking driver may provide an important estimate of the prevalence of drinking driving. Passengers of drinking drivers represent a high-risk group that is not considered in most prevention efforts. Because being a passenger of a drinking driver is not illegal, it may be an easier topic for clinicians to broach than drinking and driving.

Alcohol-influenced recreational boat operation in the United States, 1994.

BACKGROUND: There were 783 recreational boating fatalities in the United States in 1994. One contributor to this toll is alcohol-influenced operation of boats. Our study objective was to determine the prevalence of alcohol-influenced motor boat operation, and describe its relationship to demographic factors and other risk behaviors. METHODS: In 1994, a randomly dialed national telephone survey contacted 5238 adult respondents who reported on their operation of motor boats, alcohol use, and other potential injury risk behaviors. Data were weighted to obtain national estimates and percentages. RESULTS: Of 597 respondents who operated a motor boat in 1994, 31% (206 respondents) reported doing so at least once while alcohol-influenced. Alcohol-influenced operation of a motor boat was significantly more likely among males, individuals between 25 and 34 years of age, and those with greater than a college education. Alcohol-influenced motor boat operation was also more common among those who drove motor vehicles while alcohol-influenced, and those who drove a motor vehicle without using a seat belt. CONCLUSIONS: To decrease alcohol-influenced boating, new strategies should be developed. Strategies used to decrease drinking and driving motor vehicles may prove adaptable to preventing alcohol-influenced boating. More effective means of monitoring alcohol-influenced boating is needed. Alcohol use by passengers on boats should not be overlooked as a problem.

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.

Injury rates from walking, gardening, weightlifting, outdoor bicycling, and aerobics.

PURPOSE: The objective of this survey was to estimate the frequency of injuries associated with five commonly performed moderately intense activities: walking for exercise, gardening and yard work, weightlifting, aerobic dance, and outdoor bicycling. METHODS: National estimates were derived from weighted responses of over 5,000 individuals contacted between April 28 and September 18, 1994, via random-digit dialing of U.S. residential telephone numbers. Self-reported participation in these five activities in the late spring and summer of 1994 was common, ranging from an estimated 14.5 +/- 1.2% of the population for aerobics (nearly 30 million people) to 73.0 +/- 1.5% for walking (about 138 million people). RESULTS: Among participants, the activity-specific 30-d prevalence of injury ranged from 0.9 +- 0.5% for outdoor bicycle riding to 2.4 +- 1.3% for weightlifting. The estimated number in the 30 d of people injured in the 30 d before their interview ranged from 330,000 for outdoor bicycle riding to 2.1 million for gardening or yard work. Incidence rates for injury causing reduced participation in activity were 1.1 +/- 0.5x100 participantsx30 d for walking, 1.1 +/- 0.4 for gardening, and 3.3 +/- 1.9 for weightlifting. During walking and gardening, men and women were equally likely to be injured, but younger people (18-44 yr) were more likely to be injured than older people (45 + yr). Injury rates were low, yet large numbers of people were injured because participation rates were high. Most injuries were minor, but injuries may reduce participation in these otherwise beneficial activities. CONCLUSIONS: Additional studies to confirm the magnitude of the problem, to identify modifiable risk factors, and to recommend methods to reduce the frequency of such injuries are needed.