Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 33
Filtrar
1.
Animals (Basel) ; 14(4)2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38396588

RESUMO

Crocodilians are considered to be "ecosystem engineers" because their modification of habitats provides opportunities for feeding, drinking, breeding, and other vital life activities to a wide variety of other animals. One such habitat modification is the construction of nest mounds during the breeding season by most crocodilian species, including American alligators (Alligator mississippiensis). While many reports exist describing wildlife associated with alligator nests, no studies have quantified faunal associates and their corresponding behaviors while visiting nests. To address this data gap, we used automated game cameras to monitor wildlife and their behaviors at alligator nests during the egg incubation period (June-September) in coastal South Carolina, USA (2016-2021). We documented a total of 81 species (79 vertebrates and 2 invertebrates) at 78 alligator nests representing six taxonomic groups, including 48 birds (59.2%), 9 mammals (11.1%), 19 reptiles (23.4%), 3 amphibians (3.7%), 1 malacostracan (1.2%), and 1 insect (1.2%). Collectively, faunal associates primarily used alligator nests for feeding/foraging (51.8%), traveling (29.3%), and loafing (19.9%) and to a much lesser extent basking, burrowing/shelter, breeding, and nesting. However, trends in alligator nest use varied among faunal associate groups (birds, mammals, reptiles, amphibians, etc.), subgroups (e.g., passerines, raptors, wading birds, and waterfowl), and species. Several novel behaviors by some nest associates were also noted during the study, including the first observations of Virginia oppossum (Didelphis virginiana) opening and predating nests, bobcat (Lynx rufus) consuming alligator hatchlings, and Carolina wren (Thryothorus ludovicianus) feeding on the contents of a recently predated alligator egg. The results of this study indicate that a diverse assemblage of vertebrates (and some invertebrates) use alligator nest sites in coastal South Carolina for a variety of life activities during the egg incubation period, and the proportion of the behaviors exhibited varies among animal groups and species. This study provides a first step for investigations regarding the net impacts of alligator nest-faunal associate interactions and ultimately the greater ecological role of alligators and other crocodilians.

2.
Nat Commun ; 13(1): 1012, 2022 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-35197443

RESUMO

Mitigation of SARS-CoV-2 transmission from international travel is a priority. We evaluated the effectiveness of travellers being required to quarantine for 14-days on return to England in Summer 2020. We identified 4,207 travel-related SARS-CoV-2 cases and their contacts, and identified 827 associated SARS-CoV-2 genomes. Overall, quarantine was associated with a lower rate of contacts, and the impact of quarantine was greatest in the 16-20 age-group. 186 SARS-CoV-2 genomes were sufficiently unique to identify travel-related clusters. Fewer genomically-linked cases were observed for index cases who returned from countries with quarantine requirement compared to countries with no quarantine requirement. This difference was explained by fewer importation events per identified genome for these cases, as opposed to fewer onward contacts per case. Overall, our study demonstrates that a 14-day quarantine period reduces, but does not completely eliminate, the onward transmission of imported cases, mainly by dissuading travel to countries with a quarantine requirement.


Assuntos
COVID-19/prevenção & controle , Doenças Transmissíveis Importadas/prevenção & controle , Quarentena/legislação & jurisprudência , SARS-CoV-2/genética , COVID-19/epidemiologia , COVID-19/transmissão , Doenças Transmissíveis Importadas/epidemiologia , Doenças Transmissíveis Importadas/transmissão , Busca de Comunicante , Inglaterra/epidemiologia , Genoma Viral/genética , Genômica , Avaliação do Impacto na Saúde , Humanos , SARS-CoV-2/classificação , Viagem/legislação & jurisprudência , Doença Relacionada a Viagens
3.
Influenza Other Respir Viruses ; 15(3): 336-344, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33650201

RESUMO

BACKGROUND: Knowledge gaps remain regarding SARS-CoV-2 transmission on flights. We conducted a retrospective cohort study to estimate risk of acquiring symptomatic SARS-CoV-2 on aircraft, to inform contact tracing and infection control efforts. METHODS: We identified co-passengers of infectious passengers on 18 England-bound flights from European cities up to 12/03/2020, using manifests received for contact tracing. Infectious passengers were laboratory-confirmed cases with symptom onset from 7 days before to 2 days after the flight. Possible aircraft-acquired cases were laboratory-confirmed with onset 3-14 days post-flight with no known non-flight exposure. Manifests was merged with the national case management dataset (identifying cases, onset dates, contact tracing status) and the national COVID-19 linelist. Contact tracing notes were reviewed to identify non-flight exposures. We calculated attack rates (ARs) among all co-passengers and within subgroups, including by distance from infectious cases and number of infectious cases on-board. RESULTS: There were 55 infectious passengers and 2313 co-passengers, including 2221 flight-only contacts. Five possible aircraft-acquired cases were identified; ARs of 0.2% (95%CI 0.1-0.5) among all flight-only contacts and 3.8% (95%CI 1.3-10.6) among contact-traced flight-only contacts sat within a two-seat radius. The AR among 92 co-travellers with known non-flight exposure to infectious cases was 13.0% (95%CI 7.6%-21.4%). There were insufficient numbers to assess differences between subgroups. CONCLUSION: We conclude that risk of symptomatic COVID-19 due to transmission on short to medium-haul flights is low, and recommend prioritising contact-tracing of close contacts and co-travellers where resources are limited. Further research on risk on aircraft is encouraged.


Assuntos
Viagem Aérea , COVID-19/transmissão , Busca de Comunicante , SARS-CoV-2 , Adulto , COVID-19/etiologia , COVID-19/prevenção & controle , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Distanciamento Físico , Estudos Retrospectivos , Fatores de Risco , Sequenciamento Completo do Genoma
4.
Euro Surveill ; 26(5)2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33541486

RESUMO

Two London care homes experienced a second COVID-19 outbreak, with 29/209 (13.9%) SARS-CoV-2 RT-PCR-positive cases (16/103 residents, 13/106 staff). In those with prior SARS-CoV-2 exposure, 1/88 (1.1%) individuals (antibody positive: 87; RT-PCR-positive: 1) became PCR-positive compared with 22/73 (30.1%) with confirmed seronegative status. After four months protection offered by prior infection against re-infection was 96.2% (95% confidence interval (CI): 72.7-99.5%) using risk ratios from comparison of proportions and 96.1% (95% CI: 78.8-99.3%) using a penalised logistic regression model.


Assuntos
Anticorpos Antivirais/sangue , COVID-19/prevenção & controle , Surtos de Doenças/prevenção & controle , Casas de Saúde/estatística & dados numéricos , Reinfecção/prevenção & controle , SARS-CoV-2/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19/sangue , COVID-19/imunologia , Teste Sorológico para COVID-19 , Feminino , Humanos , Londres , Masculino , Pessoa de Meia-Idade , Pandemias , Reação em Cadeia da Polimerase Via Transcriptase Reversa , SARS-CoV-2/isolamento & purificação , Sequenciamento Completo do Genoma
5.
J Zoo Wildl Med ; 52(4): 1270-1274, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34998299

RESUMO

The Burmese roofed turtle (Batagur trivittata), a critically endangered freshwater turtle, is endemic to Myanmar. Once thought to be extinct, remnant wild populations were discovered in 2001 and limited captive individuals identified in pagoda ponds or confiscated from fishers in Myanmar. These and their offspring are maintained in five facilities in Myanmar and form the basis of a conservation program (habitat protection, captive breeding, nest protection, egg collection, head-starting, and release). Prerelease health screenings were performed in 2014 and 2018 at Yadanabon Zoological Gardens, a head-starting facility in Limpha Village, and Lawkanandar Wildlife Park. One hundred forty-three turtles were assessed (37 male, 50 female, 56 juveniles [too young to determine sex]; two females were assessed in both years), age range of 1 to 12 y (one unknown age adult founder), and body mass range of 0.111 to 32.72 kg. Health evaluations both years included physical examination and combined choanal/cloacal swab samples for polymerase chain reaction testing of the potential chelonian pathogens intranuclear coccidia, Mycoplasma, Herpesvirus, Ranavirus, and Adenovirus (not all tests performed each year). In 2018, cloacal swabs from 30 and 20 turtles at the Yadanabon Zoological Gardens and Lawkanandar Wildlife Park, respectively, were cultured for Salmonella. All turtles were assessed as healthy based on normal physical examination findings, and all had negative test results. Prerelease health screening, such as performed in this study, is an important component of release, reintroduction, and translocation projects to prevent introduction of novel pathogens into naïve wild populations.


Assuntos
Infecções por Adenoviridae/veterinária , Infecções por Vírus de DNA/veterinária , Infecções por Herpesviridae/veterinária , Infecções por Mycoplasma , Tartarugas , Infecções por Adenoviridae/diagnóstico , Animais , Animais de Zoológico , Infecções por Vírus de DNA/diagnóstico , Espécies em Perigo de Extinção , Feminino , Infecções por Herpesviridae/diagnóstico , Masculino , Mianmar/epidemiologia , Mycoplasma , Infecções por Mycoplasma/diagnóstico , Infecções por Mycoplasma/veterinária , Ranavirus
6.
Zootaxa ; 4821(2): zootaxa.4821.2.10, 2020 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-33056328

RESUMO

The Burmese Roofed Turtle (Batagur trivittata Duméril Bibron, 1835) is a large (straight-line carapace length [CL] to 620 mm; Platt et al., 2019), aquatic, herbivorous turtle endemic to the major river systems of Myanmar (Smith 1931; TTWG 2017). Although historically widespread and apparently abundant, long-term population declines resulted from chronic egg collecting, subsistence harvesting of adults, and loss of critical nesting habitat (Platt et al. 2017a). By the late 1990s B. trivittata was considered a candidate for Extinct status (Bhupathy et al. 2000) until a living specimen purchased in a Chinese wildlife market came into the possession of an American turtle collector in the early 2000s (Platt et al. 2005; W.P. McCord, pers. comm.). Shortly thereafter, field surveys "rediscovered" two remnant populations in the Dokhtawady and upper Chindwin Rivers (Platt et al. 2005; Kuchling et al. 2006). Intense ex- and in-situ recovery efforts were launched shortly thereafter and continue today (Kuchling Tint Lwin 2004; Çilingir et al. 2017).


Assuntos
Tartarugas , Animais , Ecossistema , Humanos , Recém-Nascido , Rios
7.
Sensors (Basel) ; 20(18)2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32942759

RESUMO

Virtual Network Functions allow the effective separation between hardware and network functionality, a strong paradigm shift from previously tightly integrated monolithic, vendor, and technology dependent deployments. In this virtualized paradigm, all aspects of network operations can be made to deploy on demand, dynamically scale, as well as be shared and interworked in ways that mirror behaviors of general cloud computing. To date, although seeing rising demand, distributed ledger technology remains largely incompatible in such elastic deployments, by its nature as functioning as an immutable record store. This work focuses on the structural incompatibility of current blockchain designs and proposes a novel, temporal blockchain design built atop federated byzantine agreement, which has the ability to dynamically scale and be packaged as a Virtual Network Function (VNF) for the 5G Core.

8.
Curr Biol ; 30(12): R721-R735, 2020 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-32574638

RESUMO

Turtles and tortoises (chelonians) have been integral components of global ecosystems for about 220 million years and have played important roles in human culture for at least 400,000 years. The chelonian shell is a remarkable evolutionary adaptation, facilitating success in terrestrial, freshwater and marine ecosystems. Today, more than half of the 360 living species and 482 total taxa (species and subspecies combined) are threatened with extinction. This places chelonians among the groups with the highest extinction risk of any sizeable vertebrate group. Turtle populations are declining rapidly due to habitat loss, consumption by humans for food and traditional medicines and collection for the international pet trade. Many taxa could become extinct in this century. Here, we examine survival threats to turtles and tortoises and discuss the interventions that will be needed to prevent widespread extinction in this group in coming decades.


Assuntos
Conservação dos Recursos Naturais , Tartarugas , Animais , Espécies em Perigo de Extinção , Extinção Biológica , Dinâmica Populacional
9.
Biol Rev Camb Philos Soc ; 95(4): 936-959, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32154985

RESUMO

Large-bodied predators are well represented among the world's threatened and endangered species. A significant body of literature shows that in terrestrial and marine ecosystems large predators can play important roles in ecosystem structure and functioning. By contrast, the ecological roles and importance of large predators within freshwater ecosystems are poorly understood, constraining the design and implementation of optimal conservation strategies for freshwater ecosystems. Conservationists and environmentalists frequently promulgate ecological roles that crocodylians are assumed to fulfil, but often with limited evidence supporting those claims. Here, we review the available information on the ecological importance of crocodylians, a widely distributed group of predominantly freshwater-dwelling, large-bodied predators. We synthesise information regarding the role of crocodylians under five criteria within the context of modern ecological concepts: as indicators of ecological health, as ecosystem engineers, apex predators, keystone species, and as contributors to nutrient and energy translocation across ecosystems. Some crocodylians play a role as indicators of ecosystem health, but this is largely untested across the order Crocodylia. By contrast, the role of crocodylian activities in ecosystem engineering is largely anecdotal, and information supporting their assumed role as apex predators is currently limited to only a few species. Whether crocodylians contribute significantly to nutrient and energy translocation through cross-ecosystem movements is unknown. We conclude that most claims regarding the importance of crocodylians as apex predators, keystone species, ecosystem engineers, and as contributors to nutrient and energy translocation across ecosystems are mostly unsubstantiated speculation, drawn from anecdotal observations made during research carried out primarily for other purposes. There is a paucity of biological research targeted directly at: understanding population dynamics; trophic interactions within their ecological communities; and quantifying the short- and long-term ecological impacts of crocodylian population declines, extirpations, and recoveries. Conservation practices ideally need evidence-based planning, decision making and justification. Addressing the knowledge gaps identified here will be important for achieving effective conservation of crocodylians.


Assuntos
Jacarés e Crocodilos/fisiologia , Conservação dos Recursos Naturais , Ecossistema , Animais , Espécies em Perigo de Extinção , Água Doce , Pesquisa/tendências
10.
J Exp Zool A Ecol Integr Physiol ; 331(10): 562-570, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31613430

RESUMO

While puberty is an animal commonality, little is known of its timing or process in crocodylians. Males copulate with an intromittent phallus that has a distinct glans morphology which directly interacts with the female cloaca, putatively effecting effective semen transfer and ultimately increased fecundity. Here we present, during the Morelet's crocodile lifecycle, a well-defined body length (65 cm snout-vent length) inflection point that marks a subsequent increase of phallic glans growth rates. Putatively, this postpubescent growth produces a copulatory-effective phallus. While not as robust of a trend as snout-vent length, this growth inflection concomitantly begins with a body condition index (CI = BM/SVL3 ) between 2.0 and 2.5 and is most distinct above a CI of 2.5. Also, in males, this 65 cm size threshold also aligns with the initiation of more robust growth in caniniform alveoli associated with prominent maxillary and mandibular teeth. This inflection was not observed in females, thus marking a sexual dimorphism that begins to present with the onset of puberty. This bodily manifestation of puberty other than those changes observed in the reproductive tracts is a novel observation for crocodylians and lays a foundation for further study among species of how changing endocrine signaling within sexually maturing males may also influence a broader range of secondary sex characteristics.


Assuntos
Jacarés e Crocodilos/crescimento & desenvolvimento , Pênis/crescimento & desenvolvimento , Maturidade Sexual , Jacarés e Crocodilos/anatomia & histologia , Animais , Feminino , Cabeça/crescimento & desenvolvimento , Masculino , Caracteres Sexuais , Dente/crescimento & desenvolvimento
11.
Acta Parasitol ; 63(4): 669-677, 2018 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-30367770

RESUMO

Falcaustra tintlwini sp. nov. (Ascaridida, Kathlaniidae) from the large intestine of Batagur trivittata (Testudines, Geoemydidae) is described and illustrated. Falcaustra tintlwini represents the 20th Oriental species assigned to the genus and is distinguished from other Oriental species by the distribution pattern of the caudal papillae (6 precloacal, 12 postcloacal, and 1 median), length of spicules (0.43-0.50 mm) and absence of a pseudosucker.


Assuntos
Intestino Grosso/parasitologia , Infecções por Spirurida/veterinária , Spirurina/classificação , Tartarugas/parasitologia , Animais , Feminino , Masculino , Mianmar , Rios , Infecções por Spirurida/parasitologia , Spirurina/anatomia & histologia , Spirurina/isolamento & purificação
12.
Environ Pollut ; 233: 1076-1085, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29042136

RESUMO

Mercury (Hg) is a persistent and widespread heavy metal with neurotoxic effects in wildlife. While bioaccumulation of Hg has historically been studied in aquatic food webs, terrestrial consumers can become contaminated with Hg when they feed on aquatic organisms (e.g., emergent aquatic insects, fish, and amphibians). However, the extent to which dietary connectivity to aquatic ecosystems can explain patterns of Hg bioaccumulation in terrestrial consumers has not been well studied. Bats (Order: Chiroptera) can serve as a model system for illuminating the trophic transfer of Hg given their high dietary diversity and foraging links to both aquatic and terrestrial food webs. Here we quantitatively characterize the dietary correlates of long-term exposure to Hg across a diverse local assemblage of bats in Belize and more globally across bat species from around the world with a comparative analysis of hair samples. Our data demonstrate considerable interspecific variation in hair total Hg concentrations in bats that span three orders of magnitude across species, ranging from 0.04 mg/kg in frugivorous bats (Artibeus spp.) to 145.27 mg/kg in the piscivorous Noctilio leporinus. Hg concentrations showed strong phylogenetic signal and were best explained by dietary connectivity of bat species to aquatic food webs. Our results highlight that phylogeny can be predictive of Hg concentrations through similarity in diet and how interspecific variation in feeding strategies influences chronic exposure to Hg and enables movement of contaminants from aquatic to terrestrial ecosystems.


Assuntos
Quirópteros/metabolismo , Monitoramento Ambiental , Poluentes Ambientais/metabolismo , Cadeia Alimentar , Mercúrio/metabolismo , Animais , Dieta , Ecossistema , Peixes , Cabelo/química , Insetos , Mercúrio/análise , Filogenia
13.
PeerJ ; 5: e3226, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28462035

RESUMO

Streptococcus pyogenes group A Streptococcus (GAS) is the most common cause of bacterial throat infections, and can cause mild to severe skin and soft tissue infections, including impetigo, erysipelas, necrotizing fasciitis, as well as systemic and fatal infections including septicaemia and meningitis. Estimated annual incidence for invasive group A streptococcal infection (iGAS) in industrialised countries is approximately three per 100,000 per year. Typing is currently used in England and Wales to monitor bacterial strains of S. pyogenes causing invasive infections and those isolated from patients and healthcare/care workers in cluster and outbreak situations. Sequence analysis of the emm gene is the currently accepted gold standard methodology for GAS typing. A comprehensive database of emm types observed from superficial and invasive GAS strains from England and Wales informs outbreak control teams during investigations. Each year the Bacterial Reference Department, Public Health England (PHE) receives approximately 3,000 GAS isolates from England and Wales. In April 2014 the Bacterial Reference Department, PHE began genomic sequencing of referred S. pyogenes isolates and those pertaining to selected elderly/nursing care or maternity clusters from 2010 to inform future reference services and outbreak analysis (n = 3, 047). In line with the modernizing strategy of PHE, we developed a novel bioinformatics pipeline that can predict emmtypes using whole genome sequence (WGS) data. The efficiency of this method was measured by comparing the emmtype assigned by this method against the result from the current gold standard methodology; concordance to emmsubtype level was observed in 93.8% (2,852/3,040) of our cases, whereas in 2.4% (n = 72) of our cases concordance was observed to emm type level. The remaining 3.8% (n = 117) of our cases corresponded to novel types/subtypes, contamination, laboratory sample transcription errors or problems arising from high sequence similarity of the allele sequence or low mapping coverage. De novo assembly analysis was performed in the two latter groups (n = 72 + 117) and was able to diagnose the problem and where possible resolve the discordance (60/72 and 20/117, respectively). Overall, we have demonstrated that our WGS emm-typing pipeline is a reliable and robust system that can be implemented to determine emm type for the routine service.

14.
R Soc Open Sci ; 4(4): 170073, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28484633

RESUMO

Mercury (Hg) is a pervasive heavy metal that often enters the environment from anthropogenic sources such as gold mining and agriculture. Chronic exposure to Hg can impair immune function, reducing the ability of animals to resist or recover from infections. How Hg influences immunity and susceptibility remains unknown for bats, which appear immunologically distinct from other mammals and are reservoir hosts of many pathogens of importance to human and animal health. We here quantify total Hg (THg) in hair collected from common vampire bats (Desmodus rotundus), which feed on blood and are the main reservoir hosts of rabies virus in Latin America. We examine how diet, sampling site and year, and bat demography influence THg and test the consequences of this variation for eight immune measures. In two populations from Belize, THg concentrations in bats were best explained by an interaction between long-term diet inferred from stable isotopes and year. Bats that foraged more consistently on domestic animals exhibited higher THg. However, relationships between diet and THg were evident only in 2015 but not in 2014, which could reflect recent environmental perturbations associated with agriculture. THg concentrations were low relative to values previously observed in other bat species but still correlated with bat immunity. Bats with higher THg had more neutrophils, weaker bacterial killing ability and impaired innate immunity. These patterns suggest that temporal variation in Hg exposure may impair bat innate immunity and increase susceptibility to pathogens such as bacteria. Unexpected associations between low-level Hg exposure and immune function underscore the need to better understand the environmental sources of Hg exposure in bats and the consequences for bat immunity and susceptibility.

15.
Conserv Biol ; 31(6): 1469-1476, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28245067

RESUMO

The Burmese roofed turtle (Batagur trivittata) is one of the world's most endangered turtles. Only one wild population remains in Myanmar. There are thought to be 12 breeding turtles in the wild. Conservation efforts for the species have raised >700 captive turtles since 2002, predominantly from eggs collected in the wild. We collected tissue samples from 445 individuals (approximately 40% of the turtles' remaining global population), applied double-digest restriction-site associated DNA sequencing (ddRAD-Seq), and obtained approximately 1500 unlinked genome-wide single nucleotide polymorphisms. Individuals fell into 5 distinct genetic clusters, 4 of which represented full-sib families. We inferred a low effective population size (≤10 individuals) but did not detect signs of severe inbreeding, possibly because the population bottleneck occurred recently. Two groups of 30 individuals from the captive pool that were the most genetically diverse were reintroduced to the wild, leading to an increase in the number of fertile eggs (n = 27) in the wild. Another 25 individuals, selected based on the same criteria, were transferred to the Singapore Zoo as an assurance colony. Our study demonstrates that the research-to-application gap in conservation can be bridged through application of cutting-edge genomic methods.


Assuntos
Conservação dos Recursos Naturais , Espécies em Perigo de Extinção , Variação Genética , Tartarugas/genética , Animais , Feminino , Masculino , Mianmar , Polimorfismo de Nucleotídeo Único
16.
Emerg Infect Dis ; 22(6): 973-80, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27192043

RESUMO

Single-strain outbreaks of Streptococcus pyogenes infections are common and often go undetected. In 2013, two clusters of invasive group A Streptococcus (iGAS) infection were identified in independent but closely located care homes in Oxfordshire, United Kingdom. Investigation included visits to each home, chart review, staff survey, microbiologic sampling, and genome sequencing. S. pyogenes emm type 1.0, the most common circulating type nationally, was identified from all cases yielding GAS isolates. A tailored whole-genome reference population comprising epidemiologically relevant contemporaneous isolates and published isolates was assembled. Data were analyzed independently using whole-genome multilocus sequencing and single-nucleotide polymorphism analyses. Six isolates from staff and residents of the homes formed a single cluster that was separated from the reference population by both analytical approaches. No further cases occurred after mass chemoprophylaxis and enhanced infection control. Our findings demonstrate the ability of 2 independent analytical approaches to enable robust conclusions from nonstandardized whole-genome analysis to support public health practice.


Assuntos
Infecção Hospitalar/epidemiologia , Surtos de Doenças , Infecções Estreptocócicas/epidemiologia , Infecções Estreptocócicas/microbiologia , Streptococcus pyogenes/genética , Alelos , Biologia Computacional/métodos , Farmacorresistência Bacteriana , Genoma Bacteriano , Genômica/métodos , Instalações de Saúde , Humanos , Filogenia , Polimorfismo de Nucleotídeo Único , Infecções Estreptocócicas/prevenção & controle , Infecções Estreptocócicas/transmissão , Streptococcus pyogenes/efeitos dos fármacos , Streptococcus pyogenes/patogenicidade , Reino Unido/epidemiologia , Virulência/genética , Sequenciamento Completo do Genoma
17.
Pediatr Infect Dis J ; 35(3): e76-84, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26569188

RESUMO

INTRODUCTION: In countries with established Haemophilus influenzae type b (Hib) immunization programs, nontypeable H. influenzae (NTHi) is now responsible for nearly all invasive H. influenzae cases across all age groups. METHODS: Public Health England (PHE) conducts enhanced national surveillance of invasive H. influenzae disease in England and Wales. Invasive NTHi isolates submitted to Public Health England from children of ages 1 month to 10 years during 2003-2010 were characterized by multilocus sequence typing (MLST). Detailed clinical information was obtained for all laboratory-confirmed cases of invasive NTHi disease in children during 2009-2013. RESULTS: In England and Wales, there were 7797 cases of invasive H. influenzae disease diagnosed during 2000-2013 and 1585 (20%) occurred in children aged 1 month to 10 years, where NTHi was responsible for 31-51 cases (incidence, 0.53-0.92/100,000) annually. Detailed clinical follow-up of 214 confirmed NTHi cases diagnosed in this age-group during 2009-2013 revealed that 52% (n = 111) occurred in <2-year-old and 52% (n=110) had comorbidity. Bacteremic pneumonia was the most common clinical presentation (n = 99, 46%), 16% (n = 34) required intensive care and 11% (n = 23) died. Characterization by biotyping and MLST of 316 NTHi strains from children with invasive disease during 2003-2010 revealed a genetically heterogeneous population (155 MLSTs) with diverse biotypes and no association with comorbidity status, clinical disease or outcome. CONCLUSIONS: The high level of genetic diversity in invasive NTHi strains highlights the difficulties in developing an effective vaccine against this pathogen.


Assuntos
Infecções por Haemophilus/epidemiologia , Infecções por Haemophilus/microbiologia , Haemophilus influenzae/classificação , Haemophilus influenzae/genética , Criança , Pré-Escolar , Inglaterra/epidemiologia , Feminino , Seguimentos , Infecções por Haemophilus/história , Haemophilus influenzae/isolamento & purificação , História do Século XXI , Humanos , Lactente , Recém-Nascido , Masculino , Epidemiologia Molecular , Tipagem de Sequências Multilocus , Filogenia , Vigilância da População , Sorogrupo , País de Gales/epidemiologia
18.
R Soc Open Sci ; 2(9): 150409, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26473062

RESUMO

The genus Crocodylus comprises 12 currently recognized species, many of which can be difficult to differentiate phenotypically. Interspecific hybridization among crocodiles is known to occur in captivity and has been documented between some species in the wild. The identification of hybrid individuals is of importance for management and monitoring of crocodilians, many of which are Convention on International Trade in Endangered Species (CITES) listed. In this study, both mitochondrial and nuclear DNA markers were evaluated for their use in confirming a suspected hybrid zone between American crocodile (Crocodylus acutus) and Morelet's crocodile (Crocodylus moreletii) populations in southern Belize where individuals and nests exhibiting atypical phenotypic features had previously been observed. Patterns observed in both phenotypic and molecular data indicate possible behavioural and ecological characteristics associated with hybridization events. The results of the combined analyses found that the majority of suspected hybrid samples represent crosses between female C. acutus and male C. moreletii. Phenotypic data could statistically identify hybrids, although morphological overlap between hybrids and C. moreletii reduced reliability of identification based solely on field characters. Ecologically, C. acutus was exclusively found in saline waters, whereas hybrids and C. moreletii were largely absent in these conditions. A hypothesized correlation between unidirectional hybridization and destruction of C. acutus breeding habitats warrants additional research.

19.
Ambio ; 42(7): 789-804, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23868440

RESUMO

High levels of species richness and endemism make Myanmar a regional priority for conservation. However, decades of economic and political sanctions have resulted in low conservation investment to effectively tackle threats to biodiversity. Recent sweeping political reforms have placed Myanmar on the fast track to economic development-the expectation is increased economic investments focused on the exploitation of the country's rich, and relatively intact, natural resources. Within a context of weak regulatory capacity and inadequate environmental safeguards, rapid economic development is likely to have far-reaching negative implications for already threatened biodiversity and natural-resource-dependent human communities. Climate change will further exacerbate prevailing threats given Myanmar's high exposure and vulnerability. The aim of this review is to examine the implications of increased economic growth and a changing climate within the larger context of biodiversity conservation in Myanmar. We summarize conservation challenges, assess direct climatological impacts on biodiversity and conclude with recommendations for long-term adaptation approaches for biodiversity conservation.


Assuntos
Biodiversidade , Mudança Climática , Conservação dos Recursos Naturais , Ecossistema , Mianmar
20.
Zoo Biol ; 31(5): 534-45, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23027550

RESUMO

The Siamese crocodile (Crocodylus siamensis) is considered one of the least studied and most critically endangered crocodilians in the world. Although few wild populations remain, more than 700,000 C. siamensis are held on commercial crocodile farms in Southeast Asia. Despite conservation concerns, many aspects of C. siamensis life history remain poorly known, particularly with regards to its reproductive biology. We studied nesting phenology, clutch characteristics, and other aspects of C. siamensis reproductive biology on crocodile farms in Cambodia during 2000 and 2001. Oviposition among captive crocodiles began in February and continued into early June. The mean (±1 SD) oviposition date based on pooled data from 2000 and 2001 was 5 April ± 24 days. Mean oviposition date differed significantly between 2000 and 2001, possibly as a result of annual variability among nesting cues. The mean incubation period was 72 ± 3 days and eggs hatched from 5 May to 18 August. Mean clutch size (25.0 ± 8.8 eggs; n = 183) differed significantly between years, possibly resulting from the >2.5-fold increase in sample size during 2001. There was no correlation between clutch size and oviposition date during either 2000 or 2001. A single female produced two clutches during 2001, complimenting previous reports of double-clutching among C. siamensis. The mean length and width of 515 eggs were 78.2 ± 4.9 and 48.1 ± 2.5 mm, respectively; mean egg mass was 90.8 ± 16.5 g (n = 471). One unpipped egg contained a set of twins.


Assuntos
Jacarés e Crocodilos/fisiologia , Animais Domésticos , Tamanho da Ninhada/fisiologia , Espécies em Perigo de Extinção , Comportamento de Nidação/fisiologia , Reprodução/fisiologia , Criação de Animais Domésticos/métodos , Animais , Camboja , Feminino
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...