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Concept: Washington, D.C.


It is widely reported that partisanship in the United States Congress is at an historic high. Given that individuals are persuaded to follow party lines while having the opportunity and incentives to collaborate with members of the opposite party, our goal is to measure the extent to which legislators tend to form ideological relationships with members of the opposite party. We quantify the level of cooperation, or lack thereof, between Democrat and Republican Party members in the U.S. House of Representatives from 1949-2012. We define a network of over 5 million pairs of representatives, and compare the mutual agreement rates on legislative decisions between two distinct types of pairs: those from the same party and those formed of members from different parties. We find that despite short-term fluctuations, partisanship or non-cooperation in the U.S. Congress has been increasing exponentially for over 60 years with no sign of abating or reversing. Yet, a group of representatives continue to cooperate across party lines despite growing partisanship.

Concepts: United States, President of the United States, United States Constitution, Washington, D.C., Democratic Party, United States House of Representatives, United States Senate, Franklin D. Roosevelt


Suicide is a major and continuing public health concern in the United States. During 1999-2015, approximately 600,000 U.S. residents died by suicide, with the highest annual rate occurring in 2015 (1). Annual county-level mortality data from the National Vital Statistics System (NVSS) and annual county-level population data from the U.S. Census Bureau were used to analyze suicide rate trends during 1999-2015, with special emphasis on comparing more urban and less urban areas. U.S. counties were grouped by level of urbanization using a six-level classification scheme. To evaluate rate trends, joinpoint regression methodology was applied to the time-series data for each level of urbanization. Suicide rates significantly increased over the study period for all county groupings and accelerated significantly in 2007-2008 for the medium metro, small metro, and non-metro groupings. Understanding suicide trends by urbanization level can help identify geographic areas of highest risk and focus prevention efforts. Communities can benefit from implementing policies, programs, and practices based on the best available evidence regarding suicide prevention and key risk factors. Many approaches are applicable regardless of urbanization level, whereas certain strategies might be particularly relevant in less urban areas affected by difficult economic conditions, limited access to helping services, and social isolation.

Concepts: Demography, Population, United States, Urban area, Washington, D.C., Suicide, Philadelphia, United States Census


Kratom (Mitragyna speciosa) is a plant consumed throughout the world for its stimulant effects and as an opioid substitute (1). It is typically brewed into a tea, chewed, smoked, or ingested in capsules (2). It is also known as Thang, Kakuam, Thom, Ketum, and Biak (3). The Drug Enforcement Administration includes kratom on its Drugs of Concern list (substances that are not currently regulated by the Controlled Substances Act, but that pose risks to persons who abuse them), and the National Institute of Drug Abuse has identified kratom as an emerging drug of abuse (3,4). Published case reports have associated kratom exposure with psychosis, seizures, and deaths (5,6). Because deaths have been attributed to kratom in the United States (7), some jurisdictions have passed or are considering legislation to make kratom use a felony (8). CDC characterized kratom exposures that were reported to poison centers and uploaded to the National Poison Data System (NPDS) during January 2010-December 2015. The NPDS is a national database of information logged by the country’s regional poison centers serving all 50 United States, the District of Columbia, and Puerto Rico and is maintained by the American Association of Poison Control Centers. NPDS case records are the result of call reports made by the public and health care providers.

Concepts: United States, Washington, D.C., U.S. state, Drug addiction, Benzodiazepine, Controlled Substances Act, Puerto Rico, Poison control center


Fatal crash risk is higher at night for all drivers, but especially for young, inexperienced drivers (1). To help address the increased crash risk for beginner teen drivers, 49 states and the District of Columbia include a night driving restriction (NDR) in their Graduated Driver Licensing (GDL) system. NDRs have been shown to reduce crashes among newly licensed teens, with higher reductions associated with NDRs starting at 10:00 p.m. or earlier (2-3). However, in 23 states and the District of Columbia, NDRs begin at 12:00 a.m. or later, times when most teen drivers subject to GDL are not driving. CDC analyzed 2009-2014 national and state-level data from the Fatality Analysis Reporting System (FARS) to determine the proportion of drivers aged 16 or 17 years involved in fatal crashes who crashed at night (9:00 p.m.-5:59 a.m.) and the proportion of these drivers who crashed before 12:00 a.m. Nationwide, among 6,104 drivers aged 16 or 17 years involved in fatal crashes during 2009-2014, 1,865 (31%) were involved in night crashes. Among drivers involved in night crashes, 1,054 (57%) crashed before 12:00 a.m. State-level analyses revealed an approximately twofold variation among states in both the proportions of drivers aged 16 or 17 years involved in fatal crashes that occurred at night and the proportions of night fatal crash involvements that occurred before 12:00 a.m. Because nearly all of the night driving trips taken by drivers aged 16 or 17 years end before 12:00 a.m., NDRs beginning at 12:00 a.m. or later provide minimal protection. States could consider updating their NDR coverage to include earlier nighttime hours. This descriptive report summarizes the characteristics of NDRs, estimates the extent to which drivers aged 16 or 17 years drive at night, and describes their involvement in fatal nighttime crashes during 2009-2014. The effects of NDRs on crashes were not evaluated because of the small state-level sample sizes during the 6-year study period.

Concepts: Washington, D.C., Driving, Driver's license, Driver's education


Kindergarten-entry vaccination requirements have played an important role in controlling vaccine-preventable diseases in the United States. Forty-eight states and the District of Colombia offer nonmedical exemptions to vaccines, ranging in stringency.

Concepts: Vaccine, Vaccination, United States, Washington, D.C., Humid subtropical climate, Organization of American States


In 2013, 45% of new human immunodeficiency virus (HIV) infection diagnoses occurred in non-Hispanic blacks/African Americans (blacks) (1), who represent 12% of the U.S.

Concepts: HIV, AIDS, Immune system, United States, Washington, D.C., New York City, Maryland, Humid subtropical climate


Close kin provide many important functions as adults age, affecting health, financial well-being, and happiness. Those without kin report higher rates of loneliness and experience elevated risks of chronic illness and nursing facility placement. Historical racial differences and recent shifts in core demographic rates suggest that white and black older adults in the United States may have unequal availability of close kin and that this gap in availability will widen in the coming decades. Whereas prior work explores the changing composition and size of the childless population or those without spouses, here we consider the kinless population of older adults with no living close family members and how this burden is changing for different race and sex groups. Using demographic microsimulation and the United States Census Bureau’s recent national projections of core demographic rates by race, we examine two definitions of kinlessness: those without a partner or living children, and those without a partner, children, siblings, or parents. Our results suggest dramatic growth in the size of the kinless population as well as increasing racial disparities in percentages kinless. These conclusions are driven by declines in marriage and are robust to different assumptions about the future trajectory of divorce rates or growth in nonmarital partnerships. Our findings draw attention to the potential expansion of older adult loneliness, which is increasingly considered a threat to population health, and the unequal burden kinlessness may place on black Americans.

Concepts: Demography, United States, Black people, Washington, D.C., Race, White American, United States Census


The U.S. government is in partial shutdown. Federal employees who are not engaged in activities considered absolutely essential are on furlough. It is like a hospital at 03:00: the skeleton crew is on, but the machine is not humming. The reason for the government shutdown is a political standoff over funding for the Affordable Care Act (ACA). Since the United States is a democracy, the best way to reopen the government - which provides numerous important services in the health sector, such as approval of drugs, devices, and diagnostics, surveillance for emerging infectious diseases, research into the biology and treatment . . .

Concepts: United States, President of the United States, United States Constitution, Federal government of the United States, Washington, D.C., U.S. state, Political philosophy, Puerto Rico


Women who enter pregnancy at a weight above or below normal weight, defined as a body mass index (BMI) of 18.5-24.9 (calculated as weight in kg/height in m2), are more likely to experience adverse pregnancy outcomes and to have infants who experience adverse health outcomes. For example, prepregnancy underweight (BMI <18.5) increases the risk for small-for-gestational-age births, whereas prepregnancy overweight (BMI 25.0-29.9) and obesity (BMI ≥30.0) increase risks for cesarean delivery, large-for-gestational-age births, and childhood obesity (1). Given these outcomes, Healthy People 2020 includes an objective to increase the proportion of women entering pregnancy with a normal weight from 52.5% in 2007 to 57.8% by 2020.* Because recent trends in prepregnancy normal weight have not been reported, CDC examined 2011-2015 National Vital Statistics System (NVSS) natality data, which included prepregnancy BMI. In 2015, for 48 states, the District of Columbia (DC), and New York City (NYC) combined, the prevalence of prepregnancy normal weight was 45.0%; prevalence ranged from 37.7% in Mississippi to 52.2% in DC. Among 38 jurisdictions with prepregnancy BMI data during 2011-2015, normal weight prevalence declined from 47.3% to 45.1%; declines were observed in all jurisdictions but were statistically significant for 27 jurisdictions after standardizing to the 2011 national maternal age and race/ethnicity distribution. Screening women's BMI during routine clinical care provides opportunities to promote normal weight before entering pregnancy.

Concepts: Childbirth, Nutrition, Obesity, Obstetrics, Body mass index, Washington, D.C., Body shape, New York City


Deaths and injuries related to firearms constitute a major public health problem in the United States. In response to firearm violence and other firearm-related injuries and deaths, an interdisciplinary, interprofessional group of leaders of 8 national health professional organizations and the American Bar Association, representing the official policy positions of their organizations, advocate a series of measures aimed at reducing the health and public health consequences of firearms. The specific recommendations include universal background checks of gun purchasers, elimination of physician “gag laws,” restricting the manufacture and sale of military-style assault weapons and large-capacity magazines for civilian use, and research to support strategies for reducing firearm-related injuries and deaths. The health professional organizations also advocate for improved access to mental health services and avoidance of stigmatization of persons with mental and substance use disorders through blanket reporting laws. The American Bar Association, acting through its Standing Committee on Gun Violence, confirms that none of these recommendations conflict with the Second Amendment or previous rulings of the U.S. Supreme Court.

Concepts: Health care, United States, Supreme Court of the United States, United States Constitution, Washington, D.C., Lawyer, Bar association, Gun politics in the United States