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Concept: Western United States


Mark Siedner and colleagues reflect on the early response to the Ebola epidemic and lessons that can be learned for future epidemics.

Concepts: Epidemiology, African American, Pandemic, Native Americans in the United States, Epidemic, Midwestern United States, Western United States


Understanding the causes and consequences of wildfires in forests of the western United States requires integrated information about fire, climate changes, and human activity on multiple temporal scales. We use sedimentary charcoal accumulation rates to construct long-term variations in fire during the past 3,000 y in the American West and compare this record to independent fire-history data from historical records and fire scars. There has been a slight decline in burning over the past 3,000 y, with the lowest levels attained during the 20th century and during the Little Ice Age (LIA, ca. 1400-1700 CE [Common Era]). Prominent peaks in forest fires occurred during the Medieval Climate Anomaly (ca. 950-1250 CE) and during the 1800s. Analysis of climate reconstructions beginning from 500 CE and population data show that temperature and drought predict changes in biomass burning up to the late 1800s CE. Since the late 1800s , human activities and the ecological effects of recent high fire activity caused a large, abrupt decline in burning similar to the LIA fire decline. Consequently, there is now a forest “fire deficit” in the western United States attributable to the combined effects of human activities, ecological, and climate changes. Large fires in the late 20th and 21st century fires have begun to address the fire deficit, but it is continuing to grow.

Concepts: 20th century, Native Americans in the United States, 21st century, Holocene, Global warming, Little Ice Age, Western United States, Medieval Warm Period


The widespread distribution of mercury (Hg) threatens wildlife health, particularly piscivorous birds. Western North America is a diverse region that provides critical habitat to many piscivorous bird species, and also has a well-documented history of mercury contamination from legacy mining and atmospheric deposition. The diversity of landscapes in the west limits the distribution of avian piscivore species, complicating broad comparisons across the region. Mercury risk to avian piscivores was evaluated across the western United States and Canada using a suite of avian piscivore species representing a variety of foraging strategies that together occur broadly across the region. Prey fish Hg concentrations were size-adjusted to the preferred size class of the diet for each avian piscivore (Bald Eagle=36cm, Osprey=30cm, Common and Yellow-billed Loon=15cm, Western and Clark’s Grebe=6cm, and Belted Kingfisher=5cm) across each species breeding range. Using a combination of field and lab-based studies on Hg effect in a variety of species, wet weight blood estimates were grouped into five relative risk categories including: background (<0.5μg/g), low (0.5-1μg/g), moderate (1-2μg/g), high (2-3μg/g), and extra high (>3μg/g). These risk categories were used to estimate potential mercury risk to avian piscivores across the west at a 1degree-by-1degree grid cell resolution. Avian piscivores foraging on larger-sized fish generally were at a higher relative risk to Hg. Habitats with a relatively high risk included wetland complexes (e.g., prairie pothole in Saskatchewan), river deltas (e.g., San Francisco Bay, Puget Sound, Columbia River), and arid lands (Great Basin and central Arizona). These results indicate that more intensive avian piscivore sampling is needed across Western North America to generate a more robust assessment of exposure risk.

Concepts: United States, Bird, North America, Los Angeles, Arizona, Columbia River, Western United States, Great Basin


We surveyed public health co-workers regarding attitudes toward a physician who returned to New Hampshire after volunteering in the West African Ebola outbreak. An unexpectedly large (18.0%) proportion of staff expressed discomfort with the Ebola responder returning to work. Employers should take proactive steps to address employee fears and concerns.

Concepts: Public health, Epidemiology, Employment, African American, Native Americans in the United States, Ebola, At-will employment, Western United States


The genetic composition of the Brazilian population was shaped by interethnic admixture between autochthonous Native Americans, Europeans settlers and African slaves. This structure, characteristic of most American populations, implies the need for large population forensic databases to capture the high diversity that is usually associated with admixed populations. In the present work, we sequenced the control region of mitochondrial DNA from 205 non-related individuals living in the Rio de Janeiro metropolitan region. Overall high haplotype diversity (0.9994 ± 0.0006) was observed, and pairwise comparisons showed a high proportion of haplotype pairs with more than one-point differences. When ignoring homopolymeric tracts, pairwise comparisons showed no differences 0.18% of the time, and differences in a single position were found with a frequency of 0.32%. A high percentage of African mtDNA was found (42%), with lineages showing a major South West origin. For the West Eurasian and Native American haplogroups (representing 32% and 26%, respectively) it was not possible to evaluate a clear geographic or linguistic affiliation. When grouping the mtDNA lineages according to their continental origin (Native American, European and African), differences were observed for the ancestry proportions estimated with autosomal ancestry-informative markers, suggesting some level of genetic substructure. The results from this study are in accordance with historical data where admixture processes are confirmed with a strong maternal contribution of African maternal ancestry and a relevant contribution of Native American maternal ancestry. Moreover, the evidence for some degree of association between mtDNA and autosomal information should be considered when combining these types of markers in forensic analysis.

Concepts: DNA, United States, Population genetics, Brazil, Native Americans in the United States, Latin America, Rio de Janeiro, Western United States


Despite advances in mechanization, logging continues to be one of the most dangerous occupations in the United States. Logging in the Intermountain West region (Montana and Idaho) is especially hazardous due to steep terrain, extreme weather, and remote work locations.

Concepts: United States, U.S. state, Native Americans in the United States, Washington, Yellowstone National Park, Extreme weather, Western United States, Intermountain West


After more than a decade of community-directed treatment with ivermectin (CDTI) in the West Region of Cameroon, epidemiological evaluation conducted in 2011 showed that onchocerciasis endemicity was still high in some communities. The conceptual framework for onchocerciasis elimination recommends in such case, to conduct additional phase 1A surveys at intervals of three to four years. Therefore, to assess the progress made towards the elimination of onchocerciasis in the West CDTI projects, we conducted a cross-sectional survey in May 2015 in 15 unevaluated communities where the highest baseline endemicity level were found in 1996. All volunteers living for at least five years in the community, aged five years or more, underwent clinical and parasitological examinations. Individual adherence to ivermectin treatment was also assessed. Analyses of data were weighted proportionally to age and gender distribution in the population.

Concepts: Epidemiology, Assessment, Western United States


The purpose of this study was to determine the prevalence and intensity as well as the factors associated with urogenital schistosomiasis (US) in Barrage, a rural community around the Mape΄ dam, in the West region of Cameroon not previously documented for transmission.

Concepts: Primary school, Primary education, School, Western United States


Objective: To describe the secular trends of institutional delivery (ID) rate in China from 1996 to 2015, and to assess the impacts of national health policies on the ID rate. Methods: Data on the number of live births and IDs for districts/counties in 31 provinces of China was annually collected by the Office for National Maternal & Child Health Statistics of China. Information concerning the relevant policies was from official governmental websites, including the programme to reduce maternal mortality and eliminate neonatal tetanus (2000 to 2008), and ID subsidy programme in rural China (2009 to present). According to the programme to reduce maternal mortality and eliminate neonatal tetanus, the calendar years were categorized into three periods: pre-programme period (1996 to 1999), programme implementation period (2000 to 2008) and post-programme period (2009 to 2015). Results: A total of 244 398 010 live births were included in the analysis, in which 211 605 727 were delivered in institutions. During the 20 years, the ID rate steadily increased from 58.7% (6 309 255/10 739 816) in 1996 to 99.7% (13 583 658/13 626 948) in 2015, with a compound annual growth rate of 2.8%. Analyses stratified by economic regions or urban-rural areas showed notably consistent increases in ID rates, and the regional and urban-rural differences became nearly disappeared by 2015. The largest regional difference between East (71.6%, 2 540 896/3 547 423) and West (44.6%, 1 675 305/3 752 873) was 27% in 1996 and <1% in 2015 (East 99.9%[5 177 865/5 180 636]and West 99.0%[3 925 766/3 964 622]). The urban-rural difference was 22.7% in 1996 (urban 73.5%[2 756 531/3 748 703], rural 50.8%[3 552 724/6 991 113]) and 0.4% in 2015(urban 99.9%[6 257 853/6 262 763], rural 99.5%[7 325 805/7 364 185]). During the programme implementation period and the post-programme period, the ID rates in rural area increased faster than those in urban area, and the corresponding compound annual growth rates in rural area were 2.4 and 2.8 times of those in urban area; the ID rates in Middle and West regions increased faster than those in East region, and the corresponding compound annual growth rates in West region were 3.6 and 6.3 times of those in East region. By 2015, the ID rates in all provinces other than Tibet (90.5%[48 445/53 505]) and Qinghai (97.2%[60 836/62 600]) reached or were close to 100%. However, there were still 112 districts/counties with ID rates <96%, of which 39 with ID rates <80%; the 39 districts/counties were all located in four western provinces (Tibet 19, Sichuan 15, Qinghai 3, and Xinjiang 2). Conclusions: During the past 20 years, the ID rate in China has steadily increased and achieved the goal of the year 2020 ahead of schedule; the regional and urban-rural inequality in ID has nearly disappeared. Given universal two-child policy, it is of significance to strengthen existing achievements, focus on complicated pregnancies and comprehensively improve the capability and quality of ID services; meanwhile, it is also of significance to develop particular policies and explore the medical-aid model for the minority-inhabited western regions with lower ID rates.

Concepts: City, People's Republic of China, Region, Tibet Autonomous Region, 175, Xinjiang, Western United States, Compound annual growth rate


There is little data on the profile and magnitude of scabies in sub-Saharan African prisons. The present study aimed to assess the prevalence and determinants of scabies in prisons of the west region of Cameroon.

Concepts: Africa, Sub-Saharan Africa, Black people, Native Americans in the United States, Subregion, African people, Western United States