14 research outputs found
Keystone structures maintain forest function for Canada lynx after large-scale spruce beetle outbreak
Central to species conservation in an era of increased disturbance from climate change is understanding the primary mechanisms that facilitate how forest-dependent species respond to changes in forest structure and composition. Here, we leveraged a natural experiment to investigate how changed forest structure and function pre-spruce-beetle ( Dendroctonus rufipennis ) and post-beetle disturbance influenced the regional distribution of Canada lynx ( Lynx canadensis ) at their southern range periphery. We compared the distribution of Canada lynx that were reintroduced into Colorado, USA from 1999–2006 to the current (2015–2017) distribution following a spatial large-scale spruce beetle outbreak from 2007 to 2016. Canada lynx did not substantially alter their distribution following the wide-spread alteration of forest structure and composition following the insect outbreak. We used the Bhattacharyya’s affinity metric to document that core (50% isopleth) and overall population ranges (95% isopleth) overlapped significantly at 50% and 77% respectively. In addition, areas of low and high relative use remained similar after the bark beetle outbreak and mapped onto one another in nearly a 1:1 fashion (Spearman rank correlation = 0.92, p < 0.01). The low impact of forest change on distribution was due to the keystone habitat elements (high horizontal forest cover, snowshoe hares) that remained functional. Thus, our results highlight that conservation scientists should increase their focus to understand the underlying mechanisms that impact wildlife distributions as climate-related disturbances becomes ever more amplified
Surveillance for Mosquitoborne Transmission of Zika Virus, New York City, NY, USA, 2016
A large number of imported cases of Zika virus infection and the potential for transmission by Aedes albopictus mosquitoes prompted the New York City Department of Health and Mental Hygiene to conduct sentinel, enhanced passive, and syndromic surveillance for locally acquired mosquitoborne Zika virus infections in New York City, NY, USA, during June–October 2016. Suspected case-patients were those >5 years of age without a travel history or sexual exposure who had >3 compatible signs/symptoms (arthralgia, fever, conjunctivitis, or rash). We identified 15 suspected cases and tested urine samples for Zika virus by using real-time reverse transcription PCR; all results were negative. We identified 308 emergency department visits for Zika-like illness, 40,073 visits for fever, and 17 unique spatiotemporal clusters of visits for fever. We identified no evidence of local transmission. Our experience offers possible surveillance tools for jurisdictions concerned about local mosquitoborne Zika virus or other arboviral transmission
Epidemiology and Burden of Hepatitis A, Malaria, and Typhoid in New York City Associated With Travel: Implications for Public Health Policy
We examined New York City Department of Health and Mental Hygiene surveillance data on hepatitis A, malaria, and typhoid to determine the proportion of these diseases related to travel and their geographic distribution. We found that 61% of hepatitis A cases, 100% of malaria cases, and 78% of typhoid cases were travel related and that cases clustered in specific populations and neighborhoods at which public health interventions could be targeted. High-risk groups include Hispanics (for hepatitis A), West Africans living in the Bronx (for malaria), and South Asians (for typhoid)
A Large Community Outbreak of Legionnaires' Disease Associated With a Cooling Tower in New York City, 2015
Objectives: Infections caused by Legionella are the leading cause of waterborne disease outbreaks in the United States. We investigated a large outbreak of Legionnaires' disease in New York City in summer 2015 to characterize patients, risk factors for mortality, and environmental exposures.
Methods: We defined cases as patients with pneumonia and laboratory evidence of Legionella infection from July 2 through August 3, 2015, and with a history of residing in or visiting 1 of several South Bronx neighborhoods of New York City. We describe the epidemiologic, environmental, and laboratory investigation that identified the source of the outbreak.
Results: We identified 138 patients with outbreak-related Legionnaires' disease, 16 of whom died. The median age of patients was 55. A total of 107 patients had a chronic health condition, including 43 with diabetes, 40 with alcoholism, and 24 with HIV infection. We tested 55 cooling towers for Legionella, and 2 had a strain indistinguishable by pulsed-field gel electrophoresis from 26 patient isolates. Whole-genome sequencing and epidemiologic evidence implicated 1 cooling tower as the source of the outbreak.
Conclusions: A large outbreak of Legionnaires' disease caused by a cooling tower occurred in a medically vulnerable community. The outbreak prompted enactment of a new city law on the operation and maintenance of cooling towers. Ongoing surveillance and evaluation of cooling tower process controls will determine if the new law reduces the incidence of Legionnaires' disease in New York City
Applying the coalitionary-traits metric: sociality without cooperation in male yellow-bellied marmots
Mammalian sociality varies both within and between species. We developed a trait-based method to quantify sociality in a continuous way to study the adaptive utility and evolution of male social behavior. The metric is based on 3 key traits--mutual tolerance, collaboration, and partner preference; males with no traits are not social, whereas those with all 3 traits are described as forming coalitions. We applied this framework to systematically describe sociality in the yellow-bellied marmot (Marmota flaviventris). Male marmot sociality varies: social groups contain one to several adult males, who may or may not monopolize reproduction. Through a series of experiments and demographic analyses, we found that male marmots do not appear to discriminate among individuals and thus do not show evidence of partner preference, males do not adjust alarm-calling behavior in a way consistent with male--male collaboration (but may alarm call to preferentially warn kin), and males do not increase their reproductive success by forming multiple-male groups. We conclude that yellow-bellied marmots show rudimentary sociality, with multiple-male groups maintained mainly by an environmental constraint and possible kin selection. The coalitionary-traits metric allowed us to systematically and objectively evaluate the degree of sociality in a socially plastic species. Copyright 2010, Oxford University Press.
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COVID-19 Outbreak - New York City, February 29-June 1, 2020
New York City (NYC) was an epicenter of the coronavirus disease 2019 (COVID-19) outbreak in the United States during spring 2020 (1). During March-May 2020, approximately 203,000 laboratory-confirmed COVID-19 cases were reported to the NYC Department of Health and Mental Hygiene (DOHMH). To obtain more complete data, DOHMH used supplementary information sources and relied on direct data importation and matching of patient identifiers for data on hospitalization status, the occurrence of death, race/ethnicity, and presence of underlying medical conditions. The highest rates of cases, hospitalizations, and deaths were concentrated in communities of color, high-poverty areas, and among persons aged ≥75 years or with underlying conditions. The crude fatality rate was 9.2% overall and 32.1% among hospitalized patients. Using these data to prevent additional infections among NYC residents during subsequent waves of the pandemic, particularly among those at highest risk for hospitalization and death, is critical. Mitigating COVID-19 transmission among vulnerable groups at high risk for hospitalization and death is an urgent priority. Similar to NYC, other jurisdictions might find the use of supplementary information sources valuable in their efforts to prevent COVID-19 infections