Mycoplasma (Class: Mollicutes) contamination in cell cultures is a universal concern for research laboratories. Some estimates report contamination in up to 35% of continuous cell lines. Various commercial antibiotic treatments can successfully decontaminate clean cell lines in vitro; however, in vitro decontamination of bacterial cultures remains challenging. Intracellular bacteria like those in the genera Rickettsia and Ehrlichia require cell culture for primary isolation and propagation and are thus vulnerable to contamination with mycoplasmas. Some analyses have reported successful antibiotic clearance of contaminating mycoplasmas in Rickettsia cultures; however, many of these studies do not identify the contaminating mycoplasma species and often include only a few isolates. To our knowledge, there are no published studies reporting decontamination of mycoplasmas from Ehrlichia cultures. In this study, we developed a specific multiplex assay to identify two of the most common mycoplasma culture contaminants, Mycoplasma arginini and Mycoplasma orale, in cell cultures infected with Rickettsia or Ehrlichia species. We further describe the successful in vitro decontamination of M. arginini, M. orale, and co-contaminations with both mycoplasmas from multiple Rickettsia and Ehrlichia cultures using daptomycin and clindamycin.IMPORTANCEMycoplasma contamination is a frequent problem in bacterial cell culture. These prolific organisms thrive in the extracellular environment in vitro and can persist in cell lines indefinitely without treatment. Historically, mycoplasma-contaminated Rickettsia cultures were cleared of contaminants by inoculating laboratory mice and re-isolating mycoplasma-free Rickettsia from brain endothelial cells. However, this method requires the sacrifice of live animals and is not always effective. Mycoplasma clearance via mouse inoculation requires a patent infection of murine central nervous system endothelial cells, which may not occur with some mildly pathogenic or nonpathogenic rickettsial species. In vitro antibiotic treatment represents an alternate method to eliminate contaminating mycoplasmas from rickettsial cultures. This method requires minimal adjustment of laboratories that already maintain rickettsial cultures and is not dependent on the use of laboratory animals. As such, the comprehensive strategy for Mycoplasma arginini and Mycoplasma orale elimination presented here can improve laboratory efficiency for in vitro research with intracellular bacteria.

Pacific Coast tick fever is a recently described zoonotic disease in California caused by a spotted fever group rickettsia, Rickettsia rickettsii subsp. californica (formerly Rickettsia 364D) and transmitted by the Pacific Coast tick, Dermacentor occidentalis. Like many emerging vector-borne diseases, knowledge regarding the transmission cycle, contribution from potential amplifying hosts, and geographic distribution of R. rickettsii californica is limited. We paired molecular analysis with comparative spatial niche modeling to identify vertebrate hosts potentially involved in the transmission cycle of this pathogen. We identified R. rickettsii californica DNA in three mammal species (Otospermophilus beecheyi, Lepus californicus, and Sylvilagus audubonii). This is the first record of R. rickettsii californica detected in mammals and may indicate potential amplifying hosts for this human pathogen. Species niche modeling of uninfected and infected D. occidentalis identified areas of high suitability along the coast and Sierra Nevada foothills of California. These findings support the hypothesis that amplifying host(s) may support higher infection prevalence in the infected tick regions compared to other parts of the tick's range. Potential host species distribution models (SDMs) were constructed from museum records and niche overlap statistics were used to compare habitat suitability with R. rickettsii californica-infected tick SDMs. We found higher than null overlap of infected ticks with California ground squirrels (O. beecheyii) and trending, but nonsignificant, overlap with two lagomorph species. Pairing molecular and niche modeling may be a useful approach to identify species that are involved in the maintenance of emerging tick-borne zoonoses.

PROBLEM/CONDITION: In 2021, approximately 75,000 persons died of violence-related injuries in the United States. This report summarizes data from CDC's National Violent Death Reporting System (NVDRS) on violent deaths that occurred in 48 states, the District of Columbia, and Puerto Rico in 2021. Results are reported by sex, age group, race and ethnicity, method of injury, type of location where the injury occurred, circumstances of injury, and other selected characteristics. This report introduces additional incident and circumstance variables, which now include child victim-specific circumstance information. This report also incorporates new U.S. Census Bureau race and ethnicity categories, which now account for more than one race and Native Hawaiian or other Pacific Islander categories and include updated denominators to calculate rates for these populations. PERIOD COVERED: 2021. DESCRIPTION OF SYSTEM: NVDRS collects data regarding violent deaths from death certificates, coroner and medical examiner records, and law enforcement reports. This report includes data collected for violent deaths that occurred in 2021. Data were collected from 48 states (all states with exception of Florida and Hawaii), the District of Columbia, and Puerto Rico. Forty-six states had statewide data, two additional states had data from counties representing a subset of their population (31 California counties, representing 64% of its population, and 13 Texas counties, representing 63% of its population), and the District of Columbia and Puerto Rico had jurisdiction-wide data. NVDRS collates information for each violent death and links deaths that are related (e.g., multiple homicides, homicide followed by suicide, or multiple suicides) into a single incident. RESULTS: For 2021, NVDRS collected information on 68,866 fatal incidents involving 70,688 deaths that occurred in 48 states (46 states collecting statewide data, 31 California counties, and 13 Texas counties), and the District of Columbia. The deaths captured in NVDRS accounted for 86.5% of all homicides, legal intervention deaths, suicides, unintentional firearm injury deaths, and deaths of undetermined intent in the United States in 2021. In addition, information was collected for 816 fatal incidents involving 880 deaths in Puerto Rico. Data for Puerto Rico were analyzed separately. Of the 70,688 deaths, the majority (58.2%) were suicides, followed by homicides (31.5%), deaths of undetermined intent that might be due to violence (8.2%), legal intervention deaths (1.3%) (i.e., deaths caused by law enforcement and other persons with legal authority to use deadly force acting in the line of duty, excluding legal executions), and unintentional firearm injury deaths (<1.0%). The term "legal intervention" is a classification incorporated into the International Classification of Diseases, Tenth Revision, and does not denote the lawfulness or legality of the circumstances surrounding a death caused by law enforcement.Demographic patterns and circumstances varied by manner of death. The suicide rate was higher for males than for females. Across all age groups, the suicide rate was highest among adults aged ≥85 years. In addition, non-Hispanic American Indian or Alaska Native (AI/AN) persons had the highest suicide rates among all racial and ethnic groups. Among both males and females, the most common method of injury for suicide was a firearm. Among all suicide victims, when circumstances were known (84.4%), suicide was most often preceded by a mental health, intimate partner, or physical health problem or by a recent or impending crisis during the previous or upcoming 2 weeks. The homicide rate was higher for males than for females. Among all homicide victims, the homicide rate was highest among persons aged 20-24 years compared with other age groups. Non-Hispanic Black or African American (Black) males experienced the highest homicide rate of any racial or ethnic group. Among all homicide victims, the most common method of injury was a firearm. When the relationship between a homicide victim and a suspect was known, the suspect was most frequently an acquaintance or friend for male victims and a current or former intimate partner for female victims. Homicide most often was precipitated by an argument or conflict, occurred in conjunction with another crime, or, for female victims, was related to intimate partner violence. Nearly all victims of legal intervention deaths were male, and the legal intervention death rate was highest among men aged 30-34 years. The legal intervention death rate was highest among AI/AN males, followed by Black males. A firearm was used in the majority of legal intervention deaths. When circumstances were known, the most frequent circumstances reported for legal intervention deaths were as follows: the victim used a weapon in the incident and the victim had a substance use problem (other than alcohol use). Other causes of death included unintentional firearm injury deaths and deaths of undetermined intent. Unintentional firearm injury deaths were most frequently experienced by males, non-Hispanic White (White) persons, and persons aged 15-24 years. These deaths most frequently occurred while the shooter was playing with a firearm and were precipitated by a person unintentionally pulling the trigger. The rate of deaths of undetermined intent was highest among males, particularly among AI/AN and Black males, and among adults aged 30-54 years. Poisoning was the most common method of injury in deaths of undetermined intent, and opioids were detected in nearly 80% of decedents tested for those substances. INTERPRETATION: This report provides a detailed summary of data from NVDRS on violent deaths that occurred in 2021. The suicide rate was highest among AI/AN and White males, whereas the homicide rate was highest among Black males. Intimate partner violence precipitated a large proportion of homicides for females. Mental health problems, intimate partner problems, interpersonal conflicts, and acute life stressors were primary precipitating circumstances for multiple types of deaths examined. PUBLIC HEALTH ACTION: Violence is preventable, and data can guide public health action. NVDRS data are used to monitor the occurrence of violence-related fatal injuries and assist public health authorities in developing, implementing, and evaluating programs, policies, and practices to reduce and prevent violent deaths. NVDRS data can be used to enhance prevention efforts into actionable strategies. States or jurisdictions have used their Violent Death Reporting System (VDRS) data to guide suicide prevention efforts and highlight where additional focus is needed. For example, North Carolina VDRS program data have played a significant role in expanding activities related to firearm safety and injury prevention. The program served as a primary data source for partners, which led to the creation of the Office of Violence Prevention in the state, focusing on combatting firearm-related deaths. In Maine, the VDRS provided data on law enforcement officer suicides that were used to help support a bill mandating mental health resiliency and awareness training in the state's law enforcement training academy, along with plans for similar training addressing mental health, substance use, and alcohol problems among corrections officers. In addition, states and jurisdictions have also used their VDRS data to examine factors related to homicide in their state or jurisdiction. For example, Georgia VDRS collaborated with the City of Atlanta Mayor's Office of Violence Reduction to develop two public dashboards that not only offer comprehensive data on violent deaths but also present data on the geographic distribution of populations disproportionately affected by violence to help inform violence prevention interventions.

Lagomorphs-principally rabbits and hares-have been implicated as hosts for vectors and reservoirs for pathogens associated with multiple rickettsial diseases. Western North America is home to diverse rickettsial pathogens which circulate among multiple wild and domestic hosts and tick and flea vectors. The purpose of this study was to assess lagomorphs and their ectoparasites in 2 locations in northern Baja California, Mexico, for exposure to and infection with rickettsial organisms. In total, 55 desert cottontail rabbits (Sylvilagus audubonii) (Baird) and 2 black-tailed jackrabbits (Lepus californicus) (Gray) were captured. In Mexicali, ticks were collected from 44% (14/32) of individuals, and were exclusively Haemaphysalis leporispalustris Neumann (Acari: Ixodidae); in Ensenada, ticks were collected from 70% (16/23) individuals, and 95% were Dermacentor parumapertus. Euhoplopsyllus glacialis affinis Baker (Siphonaptera: Pulicidae) fleas were collected from 72% of rabbits and 1 jackrabbit from Mexicali, while the few fleas found on hosts in Ensenada were Echidnophaga gallinacea Westwood (Siphonaptera: Pulicidae) and Cediopsylla inaequalis (Siphonaptera: Pulicidae). Rickettsia bellii was the only rickettsial organism detected and was identified in 88% of D. parumapertus and 67% of H. leporispalustris ticks from Ensenada. A single tissue sample from a jackrabbit was positive for R. belli (Rickettsiales: Rickettsiaceae). Hosts in Ensenada had a significantly higher prevalence of rickettsial antibodies than hosts in Mexicali (52.3% vs. 21.4%). Although R. bellii is not regarded as pathogenic in humans or other mammals, it may contribute to immunity to other rickettsiae. The marked difference in distribution of ticks, fleas, and rickettsial exposure between the 2 locations suggests that disease transmission risk may vary markedly between communities within the same region.

PROBLEM/CONDITION: In 2020, approximately 71,000 persons died of violence-related injuries in the United States. This report summarizes data from CDC's National Violent Death Reporting System (NVDRS) on violent deaths that occurred in 48 states, the District of Columbia, and Puerto Rico in 2020. Results are reported by sex, age group, race and ethnicity, method of injury, type of location where the injury occurred, circumstances of injury, and other selected characteristics. PERIOD COVERED: 2020. DESCRIPTION OF SYSTEM: NVDRS collects data regarding violent deaths obtained from death certificates, coroner and medical examiner records, and law enforcement reports. This report includes data collected for violent deaths that occurred in 2020. Data were collected from 48 states (all states with exception of Florida and Hawaii), the District of Columbia, and Puerto Rico. Forty-six states had statewide data, two additional states had data from counties representing a subset of their population (35 California counties, representing 71% of its population, and four Texas counties, representing 39% of its population), and the District of Columbia and Puerto Rico had jurisdiction-wide data. NVDRS collates information for each violent death and links deaths that are related (e.g., multiple homicides, homicide followed by suicide, or multiple suicides) into a single incident. RESULTS: For 2020, NVDRS collected information on 64,388 fatal incidents involving 66,017 deaths that occurred in 48 states (46 states collecting statewide data, 35 California counties, and four Texas counties), and the District of Columbia. In addition, information was collected for 729 fatal incidents involving 790 deaths in Puerto Rico. Data for Puerto Rico were analyzed separately. Of the 66,017 deaths, the majority (58.4%) were suicides, followed by homicides (31.3%), deaths of undetermined intent (8.2%), legal intervention deaths (1.3%) (i.e., deaths caused by law enforcement and other persons with legal authority to use deadly force acting in the line of duty, excluding legal executions), and unintentional firearm deaths (<1.0%). The term "legal intervention" is a classification incorporated into the International Classification of Diseases, Tenth Revision, and does not denote the lawfulness or legality of the circumstances surrounding a death caused by law enforcement.Demographic patterns and circumstances varied by manner of death. The suicide rate was higher for males than for females. Across all age groups, the suicide rate was highest among adults aged ≥85 years. In addition, non-Hispanic American Indian or Alaska Native (AI/AN) persons had the highest suicide rates among all racial and ethnic groups. Among both males and females, the most common method of injury for suicide was a firearm. Among all suicide victims, when circumstances were known, suicide was most often preceded by a mental health, intimate partner, or physical health problem or by a recent or impending crisis during the previous or upcoming 2 weeks. The homicide rate was higher for males than for females. Among all homicide victims, the homicide rate was highest among persons aged 20-24 years compared with other age groups. Non-Hispanic Black (Black) males experienced the highest homicide rate of any racial or ethnic group. Among all homicide victims, the most common method of injury was a firearm. When the relationship between a homicide victim and a suspect was known, the suspect was most frequently an acquaintance or friend for male victims and a current or former intimate partner for female victims. Homicide most often was precipitated by an argument or conflict, occurred in conjunction with another crime, or, for female victims, was related to intimate partner violence. Nearly all victims of legal intervention deaths were male, and the legal intervention death rate was highest among men aged 35-44 years. The legal intervention death rate was highest among AI/AN males, followed by Black males. A firearm was used in the majority of legal intervention deaths. When a specific type of crime was known to have precipitated a legal intervention death, the type of crime was most frequently assault or homicide. When circumstances were known, the three most frequent circumstances reported for legal intervention deaths were as follows: the victim's death was precipitated by another crime, the victim used a weapon in the incident, and the victim had a substance use problem (other than alcohol use).Other causes of death included unintentional firearm deaths and deaths of undetermined intent. Unintentional firearm deaths were most frequently experienced by males, non-Hispanic White (White) persons, and persons aged 15-24 years. These deaths most frequently occurred while the shooter was playing with a firearm and were precipitated by a person unintentionally pulling the trigger. The rate of deaths of undetermined intent was highest among males, particularly among AI/AN and Black males, and among adults aged 30-54 years. Poisoning was the most common method of injury in deaths of undetermined intent, and opioids were detected in nearly 80% of decedents tested for those substances. INTERPRETATION: This report provides a detailed summary of data from NVDRS on violent deaths that occurred in 2020. The suicide rate was highest among AI/AN and White males, whereas the homicide rate was highest among Black male victims. Intimate partner violence precipitated a large proportion of homicides for females. Mental health problems, intimate partner problems, interpersonal conflicts, and acute life stressors were primary circumstances for multiple types of violent death. PUBLIC HEALTH ACTION: Violence is preventable, and states and communities can use data to guide public health action. NVDRS data are used to monitor the occurrence of violence-related fatal injuries and assist public health authorities in developing, implementing, and evaluating programs, policies, and practices to reduce and prevent violent deaths. For example, the Colorado Violent Death Reporting System (VDRS), Kentucky VDRS, and Oregon VDRS have used their VDRS data to guide suicide prevention efforts and generate reports highlighting where additional focus is needed. In Colorado, VDRS data were used to examine the increased risk for suicide among first and last responders in the state. Kentucky VDRS used local data to highlight how psychological and social effects of the COVID-19 pandemic might increase risk for suicide, particularly among vulnerable populations. Oregon VDRS used their data to develop a publicly available data dashboard displaying firearm mortality trends and rates in support of the state's firearm safety campaign. Similarly, states participating in NVDRS have used their VDRS data to examine homicide in their state. Illinois VDRS, for example, found that state budget cuts were associated with notable increases in homicides among youths in Chicago. With an increase of participating states and jurisdictions, this report marks progress toward providing nationally representative data.

PROBLEM/CONDITION: In 2019, approximately 67,000 persons died of violence-related injuries in the United States. This report summarizes data from CDC's National Violent Death Reporting System (NVDRS) on violent deaths that occurred in 42 states, the District of Columbia, and Puerto Rico in 2019. Results are reported by sex, age group, race and ethnicity, method of injury, type of location where the injury occurred, circumstances of injury, and other selected characteristics. PERIOD COVERED: 2019. DESCRIPTION OF SYSTEM: NVDRS collects data regarding violent deaths obtained from death certificates, coroner and medical examiner records, and law enforcement reports. This report includes data collected for violent deaths that occurred in 2019. Data were collected from 39 states with statewide data (Alabama, Alaska, Arizona, Colorado, Connecticut, Delaware, Georgia, Hawaii, Indiana, Iowa, Kansas, Kentucky, Louisiana, Maine, Maryland, Massachusetts, Michigan, Minnesota, Missouri, Montana, Nebraska, Nevada, New Hampshire, New Jersey, New Mexico, North Carolina, North Dakota, Ohio, Oklahoma, Oregon, Rhode Island, South Carolina, Utah, Vermont, Virginia, Washington, West Virginia, Wisconsin, and Wyoming), three states with data from counties representing a subset of their population (30 California counties, representing 57% of its population, and 47 Illinois counties and 40 Pennsylvania counties, representing at least 80% of their populations), the District of Columbia, and Puerto Rico. NVDRS collates information for each violent death and links deaths that are related (e.g., multiple homicides, homicide followed by suicide, or multiple suicides) into a single incident. RESULTS: For 2019, NVDRS collected information on 50,374 fatal incidents involving 51,627 deaths that occurred in 42 states (39 states collecting statewide data, 30 California counties, 47 Illinois counties, and 40 Pennsylvania counties), and the District of Columbia. In addition, information was collected for 831 fatal incidents involving 897 deaths in Puerto Rico. Data for Puerto Rico were analyzed separately. Of the 51,627 deaths, the majority (64.1%) were suicides, followed by homicides (25.1%), deaths of undetermined intent (8.7%), legal intervention deaths (1.4%) (i.e., deaths caused by law enforcement and other persons with legal authority to use deadly force acting in the line of duty, excluding legal executions), and unintentional firearm deaths (<1.0%). The term "legal intervention" is a classification incorporated into the International Classification of Diseases, Tenth Revision, and does not denote the lawfulness or legality of the circumstances surrounding a death caused by law enforcement. Demographic patterns and circumstances varied by manner of death. The suicide rate was higher for males than for females. Across all age groups, the suicide rate was highest among adults aged 45-54 years. In addition, non-Hispanic American Indian or Alaska Native (AI/AN) and non-Hispanic White (White) persons had the highest suicide rates among all racial and ethnic groups. Among males, the most common method of injury for suicide was a firearm, whereas poisoning was the most common method of injury among females. Among all suicide victims, suicide was most often preceded by a mental health, intimate partner, or physical health problem or by a recent or impending crisis during the previous or upcoming 2 weeks. The homicide rate was higher for males than for females. Among all homicide victims, the homicide rate was highest among persons aged 20-24 years compared with other age groups. Non-Hispanic Black (Black) males experienced the highest homicide rate of any racial or ethnic group. Among all homicide victims, the most common method of injury was a firearm. When the relationship between a homicide victim and a suspect was known, the suspect was most frequently an acquaintance or friend for male victims and a current or former intimate partner for female victims. Homicide most often was precipitated by an argument or conflict, occurred in conjunction with another crime, or, for female victims, was related to intimate partner violence. Nearly all victims of legal intervention deaths were male, and the legal intervention death rate was highest among men aged 25-29 years. The legal intervention death rate was highest among AI/AN males, followed by Black males. A firearm was used in the majority of legal intervention deaths. When a specific type of crime was known to have precipitated a legal intervention death, the type of crime was most frequently assault or homicide. The three most frequent circumstances reported for legal intervention deaths were as follows: the victim's death was precipitated by another crime, the victim used a weapon in the incident, and the victim had a mental health or substance use problem (other than alcohol use). Unintentional firearm deaths were most frequently experienced by males, White persons, and persons aged 15-24 years. These deaths most frequently occurred while the shooter was playing with a firearm and were precipitated by a person unintentionally pulling the trigger or mistakenly thinking the firearm was unloaded. The rate of deaths of undetermined intent was highest among males, particularly among Black and AI/AN males, and among adults aged 30-44 years. Poisoning was the most common method of injury in deaths of undetermined intent, and opioids were detected in nearly 80% of decedents tested for those substances. INTERPRETATION: This report provides a detailed summary of data from NVDRS on violent deaths that occurred in 2019. The suicide rate was highest among AI/AN and White males, whereas the homicide rate was highest among Black males. Mental health problems, intimate partner problems, interpersonal conflicts, and acute life stressors were primary circumstances for multiple types of violent death. PUBLIC HEALTH ACTION: Violence is preventable, and data can guide public health action. NVDRS data are used to monitor the occurrence of violence-related fatal injuries and assist public health authorities in developing, implementing, and evaluating programs, policies, and practices to reduce and prevent violent deaths. For example, the New Hampshire Violent Death Reporting System (VDRS), Indiana VDRS, and Colorado VDRS have used their VDRS data to guide suicide prevention efforts and generate reports highlighting where additional focus is needed. In New Hampshire, VDRS data have been used to monitor the increase in suicide rates during 2014-2018 and guide statewide collaborative prevention efforts. Indiana VDRS used local data to demonstrate differences in suicide and other related mental health problems among Black persons and highlight a need for improved suicide awareness and culturally competent mental health care. The Colorado VDRS conducted geospatial and demographic analysis, considering local VDRS data with existing suicide prevention efforts and resources, to identify regions with high suicide rates regions and populations at high risk for suicide. Similarly, states participating in NVDRS have used their VDRS data to examine related to homicide in their state. In North Carolina for example, where homicide rates among AI/AN and Black persons were approximately 2.5 times higher than the statewide homicide rate, the North Carolina VDRS program aims to partner with historically Black colleges and universities in the state to train researchers to use VDRS data to address health equity issues in and around their immediate community.

PROBLEM/CONDITION: In 2018, approximately 68,000 persons died of violence-related injuries in the United States. This report summarizes data from CDC's National Violent Death Reporting System (NVDRS) on violent deaths that occurred in 39 states the District of Columbia, and Puerto Rico in 2018. Results are reported by sex, age group, race and ethnicity, method of injury, type of location where the injury occurred, circumstances of injury, and other selected characteristics. PERIOD COVERED: 2018. DESCRIPTION OF SYSTEM: NVDRS collects data regarding violent deaths obtained from death certificates, coroner and medical examiner reports, and law enforcement reports. This report includes data collected for violent deaths that occurred in 2018. Data were collected from 36 states with statewide data (Alabama, Alaska, Arizona, Colorado, Connecticut, Delaware, Georgia, Indiana, Iowa, Kansas, Kentucky, Louisiana, Maine, Maryland, Massachusetts, Michigan, Minnesota, Missouri, Nebraska, Nevada, New Hampshire, New Jersey, New Mexico, New York, North Carolina, Ohio, Oklahoma, Oregon, Rhode Island, South Carolina, Utah, Vermont, Virginia, Washington, West Virginia, and Wisconsin), three states with data from counties representing a subset of their population (21 California counties, 28 Illinois counties, and 39 Pennsylvania counties), the District of Columbia, and Puerto Rico. NVDRS collates information for each death and links deaths that are related (e.g., multiple homicides, homicide followed by suicide, or multiple suicides) into a single incident. RESULTS: For 2018, NVDRS collected information on 52,773 fatal incidents involving 54,170 deaths that occurred in 39 states and the District of Columbia. In addition, information was collected on 880 fatal incidents involving 975 deaths in Puerto Rico. Data for Puerto Rico were analyzed separately. Of the 54,170 deaths, the majority (64.1%) were suicides, followed by homicides (24.8%), deaths of undetermined intent (9.0%), legal intervention deaths (1.4%) (i.e., deaths caused by law enforcement and other persons with legal authority to use deadly force acting in the line of duty, excluding legal executions), and unintentional firearm deaths (<1.0%). (The term "legal intervention" is a classification incorporated into the International Classification of Diseases, Tenth Revision, and does not denote the lawfulness or legality of the circumstances surrounding a death caused by law enforcement.) Demographic patterns and circumstances varied by manner of death. The suicide rate was higher among males than among females and was highest among adults aged 35-64 years and non-Hispanic American Indian or Alaska Native (AI/AN) and non-Hispanic White persons. The most common method of injury for suicide was a firearm among males and hanging, strangulation, or suffocation among females. Suicide was most often preceded by a mental health, intimate partner, or physical health problem, or a recent or impending crisis during the previous or upcoming 2 weeks. The homicide rate was highest among persons aged 20-24 years and was higher among males than females. Non-Hispanic Black males experienced the highest homicide rate of any racial or ethnic group. The most common method of injury for homicide was a firearm. When the relationship between a homicide victim and a suspect was known, the suspect was most frequently an acquaintance or friend for male victims and a current or former intimate partner for female victims. Homicides most often were precipitated by an argument or conflict, occurred in conjunction with another crime, or, for female victims, were related to intimate partner violence. Homicide suspects were primarily male and the highest proportion were aged 25-44 years. When race and ethnicity information was known, non-Hispanic Black persons comprised the largest group of suspects overall and among those aged ≤44 years, and non-Hispanic White persons comprised the largest group of suspects among those aged ≥45 years. Almost all legal intervention deaths were experienced by males, and the legal intervention death rate was highest among males aged 30-34 years. Non-Hispanic AI/AN males had the highest legal intervention death rate, followed by non-Hispanic Black males. A firearm was used in the majority of legal intervention deaths. When a specific type of crime was known to have precipitated a legal intervention death, the type of crime was most frequently assault or homicide. The most frequent circumstances reported for legal intervention deaths were use of a weapon by the victim in the incident and a mental health or perceived substance use problem (other than alcohol use). Law enforcement officers who inflicted fatal injuries in the context of legal intervention deaths were primarily males aged 25-44 years. Unintentional firearm deaths were most frequently experienced by males, non-Hispanic White persons, and persons aged 15-24 years. These deaths most often occurred while the shooter was playing with a firearm and most frequently were precipitated by a person unintentionally pulling the trigger or mistakenly thinking that the firearm was unloaded. The rate of deaths of undetermined intent was highest among males, particularly among non-Hispanic Black and non-Hispanic AI/AN males, and among persons aged 45-54 years. Poisoning was the most common method of injury in deaths of undetermined intent, and opioids were detected in approximately 80% of decedents tested for those substances. INTERPRETATION: This report provides a detailed summary of data from NVDRS on violent deaths that occurred in 2018. The suicide rate was highest among non-Hispanic AI/AN and non-Hispanic White males, and the homicide rate was highest among non-Hispanic Black males. Mental health problems, intimate partner problems, interpersonal conflicts, and acute life stressors were primary circumstances for multiple types of violent death. Circumstances for suspects of homicide varied by age group and included having prior contact with law enforcement and involvement in incidents that were precipitated by another crime, intimate partner violence, and drug dealing or substance use. PUBLIC HEALTH ACTION: NVDRS data are used to monitor the occurrence of violence-related fatal injuries and assist public health authorities in developing, implementing, and evaluating programs, policies, and practices to reduce and prevent violent deaths. For example, Arizona and Wisconsin used their state-level VDRS data to support suicide prevention efforts within their respective states. Wisconsin VDRS used multiple years of data (2013-2017) to identify important risk and protective factors and subsequently develop a comprehensive suicide prevention plan. Arizona VDRS partners with the Arizona Be Connected Initiative to provide customized community-level data on veteran suicide deaths in Arizona. Similarly, states participating in NVDRS have used their VDRS data to examine intimate partner violence-related deaths to support prevention efforts. For example, data from the South Carolina VDRS were used to examine intimate partner homicides that occurred in South Carolina during 2017. South Carolina VDRS found that 12% of all homicides that occurred in 2017 were intimate partner violence-related, with females accounting for 52% of intimate partner homicide-related victims. These data were shared with domestic violence prevention collaborators in South Carolina to bolster their efforts in reducing intimate partner violence-related deaths. In 2018, NVDRS data included four additional states compared with 2017, providing more comprehensive and actionable violent death information for public health efforts to reduce violent deaths.

PROBLEM/CONDITION: In 2017, approximately 67,000 persons died of violence-related injuries in the United States. This report summarizes data from CDC's National Violent Death Reporting System (NVDRS) on violent deaths that occurred in 34 states, four California counties, the District of Columbia, and Puerto Rico in 2017. Results are reported by sex, age group, race/ethnicity, method of injury, type of location where the injury occurred, circumstances of injury, and other selected characteristics. PERIOD COVERED: 2017. DESCRIPTION OF SYSTEM: NVDRS collects data regarding violent deaths obtained from death certificates, coroner and medical examiner reports, and law enforcement reports. This report includes data collected for violent deaths that occurred in 2017. Data were collected from 34 states (Alaska, Arizona, Colorado, Connecticut, Delaware, Georgia, Illinois, Indiana, Iowa, Kansas, Kentucky, Maine, Maryland, Massachusetts, Michigan, Minnesota, Nevada, New Hampshire, New Jersey, New Mexico, New York, North Carolina, Ohio, Oklahoma, Oregon, Pennsylvania, Rhode Island, South Carolina, Utah, Vermont, Virginia, Washington, West Virginia, and Wisconsin), four California counties (Los Angeles, Sacramento, Shasta, and Siskiyou), the District of Columbia, and Puerto Rico. NVDRS collates information for each death and links deaths that are related (e.g., multiple homicides, homicide followed by suicide, or multiple suicides) into a single incident. RESULTS: For 2017, NVDRS collected information on 45,141 fatal incidents involving 46,389 deaths that occurred in 34 states, four California counties, and the District of Columbia; in addition, information was collected on 961 fatal incidents involving 1,027 deaths in Puerto Rico. Data for Puerto Rico were analyzed separately. Of the 46,389 deaths in the 34 states, four California counties, and District of Columbia, the majority (63.5%) were suicides, followed by homicides (24.9%), deaths of undetermined intent (9.7%), legal intervention deaths (1.4%) (i.e., deaths caused by law enforcement and other persons with legal authority to use deadly force acting in the line of duty, excluding legal executions), and unintentional firearm deaths (<1.0%). (The term "legal intervention" is a classification incorporated into the International Classification of Diseases, Tenth Revision, and does not denote the lawfulness or legality of the circumstances surrounding a death caused by law enforcement.) Demographic patterns and circumstances varied by manner of death. The suicide rate was higher among males than among females and was highest among adults aged 45-64 years and ≥85 years and non-Hispanic American Indians/Alaska Natives and non-Hispanic Whites. The most common method of injury for suicide was a firearm among males and poisoning among females. Suicide was most often preceded by a mental health, intimate partner, or physical health problem or a recent or impending crisis during the previous or upcoming 2 weeks. The homicide rate was highest among persons aged 20-24 years and was higher among males than females. Non-Hispanic Black males had the highest homicide rate of any racial/ethnic group. The most common method of injury for homicide was a firearm. When the relationship between a homicide victim and a suspect was known, the suspect was most frequently an acquaintance or friend for male victims and a current or former intimate partner for female victims. Homicide most often was precipitated by an argument or conflict, occurred in conjunction with another crime, or, for female victims, was related to intimate partner violence. Among intimate partner violence-related homicides, the largest proportion occurred among adults aged 35-54 years, and the most common method of injury was a firearm. When the relationship between an intimate partner violence-related homicide victim and a suspect was known, most female victims were killed by a current or former intimate partner, whereas approximately half of male victims were killed by a suspect who was not their intimate partner. Almost all legal intervention deaths were among males, and the legal intervention death rate was highest among men aged 25-29 years. Non-Hispanic American Indian/Alaska Native males had the highest legal intervention death rate, followed by non-Hispanic Black males. A firearm was used in the majority of legal intervention deaths. When a specific type of crime was known to have precipitated a legal intervention death, the type of crime was most frequently assault/homicide. The most frequent circumstances for legal intervention deaths were reported use of a weapon by the victim in the incident and a mental health or substance use problem (other than alcohol use). Unintentional firearm deaths more frequently occurred among males, non-Hispanic Whites, and persons aged 15-24 years. These deaths most often occurred while the shooter was playing with a firearm and most frequently were precipitated by a person unintentionally pulling the trigger or mistakenly thinking the firearm was unloaded. The rate of death when the manner was of undetermined intent was highest among males, particularly among non-Hispanic Black and non-Hispanic American Indian/Alaska Native males, and persons aged 30-34 years. Poisoning was the most common method of injury in deaths of undetermined intent, and opioids were detected in nearly 80% of decedents tested for those substances. INTERPRETATION: This report provides a detailed summary of data from NVDRS on violent deaths that occurred in 2017. The suicide rate was highest among non-Hispanic American Indian/Alaska Native and non-Hispanic White males, whereas the homicide rate was highest among non-Hispanic Black males. Intimate partner violence precipitated a large proportion of homicides for females. Mental health problems, intimate partner problems, interpersonal conflicts, and acute life stressors were primary circumstances for multiple types of violent death. PUBLIC HEALTH ACTION: NVDRS data are used to monitor the occurrence of violence-related fatal injuries and assist public health authorities in developing, implementing, and evaluating programs and policies to reduce and prevent violent deaths. For example, South Carolina VDRS and Colorado VDRS are using their data to support suicide prevention programs through systems change and the Zero Suicide framework. North Carolina VDRS and Kentucky VDRS data were used to examine intimate partner violence-related deaths beyond homicides to inform prevention efforts. Findings from these studies suggest that intimate partner violence might also contribute to other manners of violent death, such as suicide, and preventing intimate partner violence might reduce the overall number of violent deaths. In 2019, NVDRS expanded data collection to include all 50 states, the District of Columbia, and Puerto Rico, providing more comprehensive and actionable violent death information for public health efforts to reduce violent deaths.

PROBLEM/CONDITION: In 2016, approximately 65,000 persons died in the United States as a result of violence-related injuries. This report summarizes data from CDC's National Violent Death Reporting System (NVDRS) regarding violent deaths from 32 U.S. states for 2016. Results are reported by sex, age group, race/ethnicity, type of location where injured, method of injury, circumstances of injury, and other selected characteristics. PERIOD COVERED: 2016. DESCRIPTION OF SYSTEM: NVDRS collects data regarding violent deaths obtained from death certificates, coroner/medical examiner reports, law enforcement reports, and secondary sources (e.g., child fatality review team data, Supplementary Homicide Reports, hospital data, and crime laboratory data). This report includes data collected from 32 states for 2016 (Alaska, Arizona, Colorado, Connecticut, Georgia, Hawaii, Illinois, Indiana, Iowa, Kansas, Kentucky, Maine, Maryland, Massachusetts, Michigan, Minnesota, New Hampshire, New Jersey, New Mexico, New York, North Carolina, Ohio, Oklahoma, Oregon, Pennsylvania, Rhode Island, South Carolina, Utah, Vermont, Virginia, Washington, and Wisconsin). NVDRS collates information for each death and links deaths that are related (e.g., multiple homicides, homicide followed by suicide, or multiple suicides) into a single incident. RESULTS: For 2016, NVDRS captured 40,374 fatal incidents involving 41,466 deaths in the 32 states included in this report. The majority (62.3%) of deaths were suicides, followed by homicides (24.9%), deaths of undetermined intent (10.8%), legal intervention deaths (1.2%) (i.e., deaths caused by law enforcement and other persons with legal authority to use deadly force acting in the line of duty, excluding legal executions), and unintentional firearm deaths (<1.0%). (The term legal intervention is a classification incorporated into the International Classification of Diseases, Tenth Revision [ICD-10] and does not denote the lawfulness or legality of the circumstances surrounding a death caused by law enforcement.) Demographic patterns varied by manner of death. Suicide rates were highest among males, non-Hispanic American Indians/Alaska Natives, non-Hispanic whites, adults aged 45-64 years, and men aged >/=75 years. The most common method of injury was a firearm among males and poisoning among females. Suicides were most often preceded by a mental health, intimate partner, substance abuse, or physical health problem or a recent or impending crisis during the previous or upcoming 2 weeks. Homicide rates were highest among males and persons aged <1 year and 15-44 years. Among males, non-Hispanic blacks accounted for most homicides and had the highest rate of any racial/ethnic group. The most common method of injury was a firearm. Homicides were most often precipitated by an argument or conflict, occurred in conjunction with another crime, or for females, were related to intimate partner violence. When the relationship between a homicide victim and a suspected perpetrator was known, the suspect was most frequently an acquaintance/friend among males and a current or former intimate partner among females. Legal intervention death rates were highest among men aged 20-44 years, and the rate among non-Hispanic black males was three times the rate among non-Hispanic white males. Precipitating circumstances for legal intervention deaths most frequently were an alleged criminal activity in progress, reported use of a weapon by the victim in the incident, a mental health or substance abuse problem (other than alcohol abuse), an argument or conflict, or a recent or impending crisis. Unintentional firearm deaths were more frequent among males, non-Hispanic whites, and persons aged 15-24 years. These deaths most often occurred while the shooter was playing with a firearm and most often were precipitated by a person unintentionally pulling the trigger or mistakenly thinking the firearm was unloaded. Rates of deaths of undetermined intent were highest among males, particularly non-Hispanic black and American Indian/Alaska Native males, and adults aged 25-64 years. Substance abuse, mental health problems, physical health problems, and a recent or impending crisis were the most common circumstances preceding deaths of undetermined intent. In 2016, a total of 3,655 youths aged 10-24 years died by suicide. The majority of these decedents were male, non-Hispanic white, and aged 18-24 years. Most decedents aged 10-17 years died by hanging/strangulation/suffocation (49.3%), followed by a firearm (40.4%), and suicides among this age group were most often precipitated by mental health, family relationship, and school problems. Most suicides among decedents aged 18-24 years were by a firearm (46.2%), followed by hanging/strangulation/suffocation (37.4%), and were precipitated by mental health, substance abuse, intimate partner, and family problems. A recent crisis, an argument or conflict, or both were common precipitating circumstances among all youth suicide decedents. INTERPRETATION: This report provides a detailed summary of data from NVDRS for 2016. Suicides rates were highest among non-Hispanic American Indian/Alaska Native and white males, whereas homicide rates were highest among non-Hispanic black males. Mental health problems, intimate partner problems, interpersonal conflicts, and acute life stressors were primary precipitating events for multiple types of violent deaths, including suicides among youths aged 10-24 years. PUBLIC HEALTH ACTION: NVDRS data are used to monitor the occurrence of violence-related fatal injuries and assist public health authorities in the development, implementation, and evaluation of programs and policies to reduce and prevent violent deaths. For example, Utah VDRS data were used to help identify suicide risk factors among youths aged 10-17 years, Rhode Island VDRS suicide data were analyzed to identify precipitating circumstances of youth suicides over a 10-year period, and Kansas VDRS data were used by the Kansas Youth Suicide Prevention Task Force. In 2019, NVDRS expanded data collection to include all 50 states, Puerto Rico, and the District of Columbia. This expansion is essential to public health efforts to reduce violent deaths.

PROBLEM/CONDITION: In 2015, approximately 62,000 persons died in the United States as a result of violence-related injuries. This report summarizes data from CDC's National Violent Death Reporting System (NVDRS) regarding violent deaths from 27 U.S. states for 2015. Results are reported by sex, age group, race/ethnicity, location of injury, method of injury, circumstances of injury, and other selected characteristics. REPORTING PERIOD: 2015. DESCRIPTION OF SYSTEM: NVDRS collects data regarding violent deaths obtained from death certificates, coroner/medical examiner reports, law enforcement reports, and secondary sources (e.g., child fatality review team data, supplemental homicide reports, hospital data, and crime laboratory data). This report includes data from 27 states that collected statewide data for 2015 (Alaska, Arizona, Colorado, Connecticut, Georgia, Hawaii, Kansas, Kentucky, Maine, Maryland, Massachusetts, Michigan, Minnesota, New Hampshire, New Jersey, New Mexico, New York, North Carolina, Ohio, Oklahoma, Oregon, Rhode Island, South Carolina, Utah, Vermont, Virginia, and Wisconsin). NVDRS collates documents for each death and links deaths that are related (e.g., multiple homicides, a homicide followed by a suicide, or multiple suicides) into a single incident. RESULTS: For 2015, NVDRS captured 30,628 fatal incidents involving 31,415 deaths in the 27 states included in this report. The majority (65.1%) of deaths were suicides, followed by homicides (23.5%), deaths of undetermined intent (9.5%), legal intervention deaths (1.3%) (i.e., deaths caused by law enforcement and other persons with legal authority to use deadly force, excluding legal executions), and unintentional firearm deaths (<1.0%). (The term "legal intervention" is a classification incorporated into the International Classification of Diseases, Tenth Revision [ICD-10] and does not denote the lawfulness or legality of the circumstances surrounding a death caused by law enforcement.) Demographic patterns varied by manner of death. Suicide rates were highest among males, non-Hispanic American Indian/Alaska Natives, non-Hispanic whites, adults aged 45-54 years, and men aged >/=75 years. The most common method of injury was a firearm. Suicides often were preceded by a mental health, intimate partner, substance abuse, or physical health problem, or a crisis during the previous or upcoming 2 weeks. Homicide rates were higher among males and persons aged <1 year and 20-34 years. Among males, non-Hispanic blacks accounted for the majority of homicides and had the highest rate of any racial/ethnic group. Homicides primarily involved a firearm, were precipitated by arguments and interpersonal conflicts, were related to intimate partner violence (particularly for females), or occurred in conjunction with another crime. When the relationship between a homicide victim and a suspected perpetrator was known, an acquaintance/friend or an intimate partner frequently was involved. Legal intervention death rates were highest among males and persons aged 20-54 years; rates among non-Hispanic black males were approximately double the rates of those among non-Hispanic white males. Precipitating circumstances for legal intervention deaths most frequently were an alleged criminal activity in progress, the victim reportedly using a weapon in the incident, a mental health or substance abuse problem (other than alcohol abuse), an argument or conflict, or a recent crisis (during the previous or upcoming 2 weeks). Unintentional firearm deaths were more frequent among males, non-Hispanic whites, and persons aged 10-24 years; these deaths most often occurred while the shooter was playing with a firearm and most often were precipitated by a person unintentionally pulling the trigger or mistakenly thinking the firearm was unloaded. Deaths of undetermined intent were more frequent among males, particularly non-Hispanic black and American Indian/Alaska Native males, and persons aged 30-54 years. Substance abuse, mental health problems, physical health problems, and a recent crisis were the most common circumstances preceding deaths of undetermined intent. In 2015, approximately 3,000 current or former military personnel died by suicide. The majority of these decedents were male, non-Hispanic white, and aged 45-74 years. Most suicides among military personnel involved a firearm and were precipitated by mental health, physical health, and intimate partner problems, as well as a recent crisis. INTERPRETATION: This report provides a detailed summary of data from NVDRS for 2015. The results indicate that deaths resulting from self-inflicted or interpersonal violence most frequently affect males and certain age groups and minority populations. Mental health problems, intimate partner problems, interpersonal conflicts, and general life stressors were primary precipitating events for multiple types of violent deaths, including suicides among current or former military personnel. PUBLIC HEALTH ACTION: NVDRS data are used to monitor the occurrence of violence-related fatal injuries and assist public health authorities in the development, implementation, and evaluation of programs and policies to reduce and prevent violent deaths. For example, Virginia VDRS data are used to help identify suicide risk factors among active duty service members, Oregon VDRS suicide data are used to coordinate information and activities across community agencies that support veterans and active duty service members, and Arizona VDRS data are used to develop recommendations for primary care providers who deliver care to veterans. The continued development and expansion of NVDRS to include all 50 states, U.S. territories, and the District of Columbia are essential to public health efforts to reduce deaths due to violence.

PROBLEM/CONDITION: In 2014, approximately 59,000 persons died in the United States as a result of violence-related injuries. This report summarizes data from CDC's National Violent Death Reporting System (NVDRS) regarding violent deaths from 18 U.S. states for 2014. Results are reported by sex, age group, race/ethnicity, marital status, location of injury, method of injury, circumstances of injury, and other selected characteristics. REPORTING PERIOD COVERED: 2014. DESCRIPTION OF SYSTEM: NVDRS collects data from participating states regarding violent deaths. Data are obtained from death certificates, coroner/medical examiner reports, law enforcement reports, and secondary sources (e.g., child fatality review team data, supplemental homicide reports, hospital data, and crime laboratory data). This report includes data from 18 states that collected statewide data for 2014 (Alaska, Colorado, Georgia, Kentucky, Maryland, Massachusetts, Michigan, New Jersey, New Mexico, North Carolina, Ohio, Oklahoma, Oregon, Rhode Island, South Carolina, Utah, Virginia, and Wisconsin). NVDRS collates documents for each death and links deaths that are related (e.g., multiple homicides, a homicide followed by a suicide, or multiple suicides) into a single incident. RESULTS: For 2014, a total of 22,098 fatal incidents involving 22,618 deaths were captured by NVDRS in the 18 states included in this report. The majority of deaths were suicides (65.6%), followed by homicides (22.5%), deaths of undetermined intent (10.0%), deaths involving legal intervention (1.3%) (i.e., deaths caused by law enforcement and other persons with legal authority to use deadly force, excluding legal executions), and unintentional firearm deaths (<1%). The term "legal intervention" is a classification incorporated into the International Classification of Diseases, Tenth Revision (ICD-10) and does not denote the lawfulness or legality of the circumstances surrounding a death caused by law enforcement. Suicides occurred at higher rates among males, non-Hispanic American Indian/Alaska Natives (AI/AN), non-Hispanic whites, persons aged 45-54 years, and males aged >/=75 years. Suicides were preceded primarily by a mental health, intimate partner, substance abuse, or physical health problem or a crisis during the previous or upcoming 2 weeks. Homicide rates were higher among males and persons aged <1 year and 15-44 years; rates were highest among non-Hispanic black and AI/AN males. Homicides primarily were precipitated by arguments and interpersonal conflicts, occurrence in conjunction with another crime, or related to intimate partner violence (particularly for females). When the relationship between a homicide victim and a suspected perpetrator was known, it was most often either an acquaintance/friend or an intimate partner. Legal intervention death rates were highest among males and persons aged 20-44 years; rates were highest among non-Hispanic black males and Hispanic males. Precipitating factors for the majority of legal intervention deaths were alleged criminal activity in progress, the victim reportedly using a weapon in the incident, a mental health or substance abuse problem, an argument or conflict, or a recent crisis. Deaths of undetermined intent occurred more frequently among males, particularly non-Hispanic black and AI/AN males, and persons aged 30-54 years. Substance abuse, mental health problems, physical health problems, and a recent crisis were the most common circumstances preceding deaths of undetermined intent. Unintentional firearm deaths were more frequent among males, non-Hispanic whites, and persons aged 10-24 years; these deaths most often occurred while the shooter was playing with a firearm and were most often precipitated by a person unintentionally pulling the trigger or mistakenly thinking the firearm was unloaded. INTERPRETATION: This report provides a detailed summary of data from NVDRS for 2014. The results indicate that violent deaths resulting from self-inflicted or interpersonal violence disproportionately affected persons aged <65 years, males, and certain minority populations. The primary precipitating factors for homicides and suicides were intimate partner problems, interpersonal conflicts, mental health and substance abuse problems, and recent crises. PUBLIC HEALTH ACTION: NVDRS data are used to monitor the occurrence of violence-related fatal injuries and assist public health authorities in the development, implementation, and evaluation of programs and policies to reduce and prevent violent deaths. For example, North Carolina VDRS data were used to improve case ascertainment of pregnancy-associated suicides, Wisconsin VDRS data were used to develop the statewide suicide prevention strategy, and Colorado VDRS data were used to develop programs and prevention strategies for suicide among veterans. The continued development and expansion of NVDRS to include all U.S. states, territories, and the District of Columbia are essential to public health efforts to reduce the impact of violence.

OBJECTIVE: This research assessed the reduction of peak levels, equivalent energy and sound power of firearm suppressors. DESIGN: The first study evaluated the effect of three suppressors at four microphone positions around four firearms. The second study assessed the suppressor-related reduction of sound power with a 3 m hemispherical microphone array for two firearms. RESULTS: The suppressors reduced exposures at the ear between 17 and 24 dB peak sound pressure level and reduced the 8 h equivalent A-weighted energy between 9 and 21 dB depending upon the firearm and ammunition. Noise reductions observed for the instructor's position about a metre behind the shooter were between 20 and 28 dB peak sound pressure level and between 11 and 26 dB LAeq,8h. Firearm suppressors reduced the measured sound power levels between 2 and 23 dB. Sound power reductions were greater for the low-velocity ammunition than for the same firearms fired with high-velocity ammunition due to the effect of N-waves produced by a supersonic bullet. CONCLUSIONS: Firearm suppressors may reduce noise exposure, and the cumulative exposures of suppressed firearms can still present a significant hearing risk. Therefore, firearm users should always wear hearing protection whenever target shooting or hunting.

In the United States and other parts of the world, recreational firearm shooting is a popular sport that puts the hearing of the shooter at risk. Peak sound pressure levels (SPLs) from firearms range from approximately 140 to 175 dB. The majority of recreational firearms (excluding small-caliber 0.17 and 0.22 rifles and air rifles) generate between 150 and 165 dB peak SPLs. High-intensity impulse sounds will permanently damage delicate cochlear structures, and thus individuals who shoot firearms are at a higher risk of bilateral, high-frequency, noise-induced hearing loss (NIHL) than peer groups who do not shoot. In this article, we describe several factors that influence the risk of NIHL including the use of a muzzle brake, the number of shots fired, the distance between shooters, the shooting environment, the choice of ammunition, the use of a suppressor, and hearing protection fit and use. Prevention strategies that address these factors and recommendations for specialized hearing protectors designed for shooting sports are offered. Partnerships are needed between the hearing health community, shooting sport groups, and wildlife conservation organizations to develop and disseminate accurate information and promote organizational resources that support hearing loss prevention efforts.

OBJECTIVES: Examine fatal and nonfatal firearm injuries among children aged 0 to 17 in the United States, including intent, demographic characteristics, trends, state-level patterns, and circumstances. METHODS: Fatal injuries were examined by using data from the National Vital Statistics System and nonfatal injuries by using data from the National Electronic Injury Surveillance System. Trends from 2002 to 2014 were tested using joinpoint regression analyses. Incident characteristics and circumstances were examined by using data from the National Violent Death Reporting System. RESULTS: Nearly 1300 children die and 5790 are treated for gunshot wounds each year. Boys, older children, and minorities are disproportionately affected. Although unintentional firearm deaths among children declined from 2002 to 2014 and firearm homicides declined from 2007 to 2014, firearm suicides decreased between 2002 and 2007 and then showed a significant upward trend from 2007 to 2014. Rates of firearm homicide among children are higher in many Southern states and parts of the Midwest relative to other parts of the country. Firearm suicides are more dispersed across the United States with some of the highest rates occurring in Western states. Firearm homicides of younger children often occurred in multivictim events and involved intimate partner or family conflict; older children more often died in the context of crime and violence. Firearm suicides were often precipitated by situational and relationship problems. The shooter playing with a gun was the most common circumstance surrounding unintentional firearm deaths of both younger and older children. CONCLUSIONS: Firearm injuries are an important public health problem, contributing substantially to premature death and disability of children. Understanding their nature and impact is a first step toward prevention.

OBJECTIVE: This study describes signals generated by .22 and .32 caliber starter pistols in the context of noise-induced hearing loss risk for sports officials and athletes. DESIGN: Acoustic comparison of impulses generated from typical .22 and .32 caliber starter pistols firing blanks were made to impulses generated from comparable firearms firing both blanks and live rounds. Acoustic characteristics are described in terms of directionality and distance from the shooter in a simulated outdoor running track. Metrics include peak sound pressure levels (SPL), A-weighted equivalent 8-hour level (L eqA8 ), and maximum permissible number of individual shots, or maximum permissible exposures (MPE) for the unprotected ear. RESULTS: Starter pistols produce peak SPLs above 140 dB. The numbers of MPEs are as few as five for the .22-caliber starter pistol, and somewhat higher (≤25) for the .32-caliber pistol. CONCLUSION: The impulsive sounds produced by starter pistols correspond to MPE numbers that are unacceptably small for unprotected officials and others in the immediate vicinity of the shooter. At the distances included in this study, the risk to athletes appears to be low (when referencing exposure criteria for adults), but the sound associated with the starter pistol will contribute to the athlete’s overall noise exposure.