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Foetal birth weight is an important determinant of perinatal health. For this reason, various methods have been investigated for estimating this weight during pregnancy. The aim of this study is to evaluate the possible relationship between full-term birth weight and pregnancy-associated plasma protein-A (PAPP-A) levels determined during the first trimester as part of combined screening for aneuploidy carried out in pregnant women. We carried out a single-centre study including pregnant women who were being followed up by the Obstetrics Service Care Units of the XXI de Santiago de Compostela e Barbanza Foundation, who gave birth from March 1, 2015, to March 1, 2017, and who had undergone their first-trimester combined chromosomopathy screening. The sample included a total of 2794 women. We found a significant correlation between MoM PAPP-A and foetal birth weight. When MoM PAPP-A was measured at extremely low levels (< 0.3) during the first trimester, the OR for giving birth to a foetus with weight < p10, adjusting for gestational age and sex, was 2.74. For low levels of MoM PAPP-A (0.3-0.44), the OR was 1.52. With regard to the value of MOM PAPP-A levels as a predictor of foetal macrosomia, a correlation could be observed with elevated levels, although this was not statistically significant. PAPP-A determined during the first trimester acts as a predictor of foetal weight at term as well as for foetal growth disorders.
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Macrossomia Fetal , Proteína Plasmática A Associada à Gravidez , Gravidez , Humanos , Feminino , Primeiro Trimestre da Gravidez , Peso ao Nascer , Parto , BiomarcadoresRESUMO
BACKGROUND: Currently, ketamine is not often used as an anesthetic. Its clinical characteristics and mechanism of action largely depend on antagonism of the N-methyl-D-aspartate receptor. OBJECTIVE: To evaluate the utility of oral ketamine as a preanesthetic agent to lower surgical stress for patients with mental disability. MATERIAL AND METHODS: Observational, retrospective study of 112 mentally disabled patients undergoing major dental surgery on an outpatient basis. The study group received oral midazolam, ibuprofen, and 6 mg/kg of ketamine; the control group received only midazolam and ibuprofen. We recorded data concerning demographics, anesthesia, surgery, physiologic variables, Glasgow score, time of onset of anxiolysis, duration of stay in the recovery ward, and adverse events. RESULTS: Conservative odontologic treatment was provided in 66.3% of the cases. Seventy-one patients (64.4%) were in the control group and 41 patients (36.6%) in the study group. Hemodynamic, respiratory, and neurologic changes were minimal and there were no significant between-group differences. Level of sedation differed significantly between groups (P = .001) at 15 and 30 minutes; differences were also observed within the study group. Mean (SD) duration of surgery was 72.6 (29.7) minutes. Mean duration of stay in the postoperative recovery ward was 140.9 (52.1) minutes (135.8 [54.89] minutes in the study group and 144.2 [50.5] minutes in the control group). The incidence of adverse events did not differ significantly between groups. CONCLUSIONS: Oral ketamine is an effective premedication for major ambulatory surgery and does not increase the incidence of side effects.
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Adjuvantes Anestésicos/administração & dosagem , Procedimentos Cirúrgicos Ambulatórios , Anestésicos Dissociativos/administração & dosagem , Ketamina/administração & dosagem , Transtornos Mentais , Midazolam/administração & dosagem , Medicação Pré-Anestésica , Administração Oral , Estudos Transversais , Feminino , Humanos , Masculino , Estudos Prospectivos , Estudos Retrospectivos , Adulto JovemRESUMO
INTRODUCTION: The principal objective was to determine the incidence rate of adverse drug events (ADEs) in hospitalised patients and evaluate the event prevention percentage. METHODS: Multi-centre, prospective observational study lasting four months, performed in five hospitals providing different levels of care. We included all adult patients who were admitted to one of the selected centres for longer than 48 hours and who required pharmacological treatment. ADEs were identified by direct observation and the use of previously defined alarm signals. The Karch-Lasagna scale was used to determine the causality relationship, and the Schumock and Thornton questionnaire adapted by Otero was used to evaluate ADE preventability. Preventable drug-induced adverse events were classified according to the taxonomy that the Ruiz-Jarabo 2000 group defined, and coordinated by ISMP-Spain. RESULTS: We included 1,550 patients, 159 of whom experienced at least one ADE (10.3 %). The preventability percentage was 51.6 %, which represented 5.3 % of the total sample. The endocrine system (34.8 %) and the cardiovascular system (20.7 %) were the most affected by preventable ADEs. Antibiotics were responsible for 16.5 % of all ADEs. 9.3 % of all preventable ADEs were triggered by use of opiates. The vast majority of preventable ADEs (36.3 %) resulted from omitting a necessary medication. Only 4.4 % of preventable ADEs are considered to be serious. CONCLUSIONS: There is a high incidence rate of ADEs during patients' hospital stay (10.3 %), and half of them (51.6 %) could have been prevented. Implementation of an automatic alarm system and certain best practices for problem spots along the care circuit will help detect and avoid preventable ADEs.
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Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Adulto , Sistemas de Notificação de Reações Adversas a Medicamentos , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Causalidade , Alarmes Clínicos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/classificação , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/diagnóstico , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/prevenção & controle , Feminino , Hospitalização , Humanos , Incidência , Masculino , Erros de Medicação/estatística & dados numéricos , Pessoa de Meia-Idade , Preparações Farmacêuticas/classificação , Estudos Prospectivos , Fatores de Risco , Espanha/epidemiologia , Inquéritos e QuestionáriosRESUMO
From 1998 to 2003, 4,935 hunter-killed deer in northern and central Illinois were examined for ticks; 4,066 blacklegged ticks, Ixodes scapularis Say, and 6,530 winter ticks, Dermacentor albipictus (Packard) (Acari: Ixodidae), were collected. I. scapularis was the predominant tick species in the northern portion of the study area, with a decreasing north-to-south prevalence gradient. In contrast, D. albipictus was more common in the south with a decreasing south-to-north prevalence gradient. Compared with previous studies, the geographic range for both species expanded into the central portion of the Illinois River. Prevalence and intensity of both tick species were greater on bucks, and infested bucks were geographically more widespread than infested does and fawns. These findings indicate that blacklegged tick and winter tick distributions remain dynamic in the north central United States
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Cervos/parasitologia , Dermacentor , Ixodes , Infestações por Carrapato/veterinária , Animais , Feminino , Geografia , Illinois/epidemiologia , Masculino , Vigilância da População/métodos , Prevalência , Rios , Infestações por Carrapato/epidemiologia , Fatores de TempoRESUMO
The risk of Lyme disease for humans in the eastern United States is dependent on the density of host-seeking Ixodes scapularis Say nymphal stage ticks infected with Borrelia burgdorferi. Although many local and regional studies have estimated Lyme disease risk using these parameters, this is the first large-scale study using a standardized methodology. Density of host-seeking I. scapularis nymphs was measured by drag sampling of closed canopy deciduous forest habitats in 95 locations spaced among 2 degrees quadrants covering the entire United States east of the 100th meridian. Sampling was done in five standardized transects at each site and repeated three to six times during the summer of 2004. The total number of adults and nymphs of the seven tick species collected was 17,972, with 1,405 nymphal I. scapularis collected in 31 of the 95 sites. Peak global spatial autocorrelation values were found at the smallest lag distance (300 km) and decreased significantly after 1,000 km. Local auto-correlation statistics identified two significant high-density clusters around endemic areas in the northeast and upper Midwest and a low-density cluster in sites south of the 39th parallel, where only 21 nymphs were collected. Peak nymphal host-seeking density occurred earlier in the southern than in the most northern sites. Spatiotemporal density patterns will be combined with Borrelia prevalence data as part of a 4-yr survey to generate a nationwide spatial risk model for I. scapularis-borne Borrelia, which will improve targeting of disease prevention efforts.
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Vetores Aracnídeos/fisiologia , Ixodes/fisiologia , Animais , Análise por Conglomerados , Geografia , Ninfa/fisiologia , Densidade Demográfica , Estatística como Assunto , Fatores de Tempo , Estados UnidosRESUMO
PURPOSE: To evaluate the outcomes in our hospital of an ambulatory major surgery program in patients with a variety of different ocular pathologies. METHOD: This retrospective study includes 13,878 patients who underwent programmed surgery by the Department of Ophthalmology between September 1998 and December 2004. Different ophthalmological surgical procedures were performed as outpatient surgery in 11,187 patients, with cataract surgery (phacoemulsification) being the most frequent operation performed (8,155 cases). We have analysed several indicators (substitution, suspension, admission and readmission rates), as well as surgical yield and systemic and ocular complications which appeared within 72 hours after surgery. The variables were measured as relative frequencies. The evolution of complications during the study period was analysed by the Chi-square trend test. RESULTS: 13,878 patients had ophthalmic surgery during the study period; 11,187 had outpatient surgery with a global substitution ratio of 80.6%. The median surgical yield was 74.36%. The admission rate after surgery was 4.46% (499 patients), with 92.18% (460) of these requiring immediate admission. Twenty-one patients suffered from severe complications (cardiovascular, neurological, metabolic, infectious), representing a proportional risk of 1:532. Forty-five patients had less severe complications (arterial hypertension, nausea, vomiting, vasovagal syncope) that required admission to hospital. Ophthalmologic complications occurred in 79 cases (0.56%). CONCLUSIONS: Ambulatory major surgery (AMS) is an excellent organization model of multidisciplinary surgical assistance that makes it possible to treat well selected patients in an effective, safe and efficient manner. There is a low incidence of postoperative complications of variable severity despite following the optimum requisites, although fortunately mortality is practically absent.
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Procedimentos Cirúrgicos Ambulatórios/estatística & dados numéricos , Procedimentos Cirúrgicos Oftalmológicos/estatística & dados numéricos , Ambulatório Hospitalar/estatística & dados numéricos , Idoso , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Endoftalmite/epidemiologia , Endoftalmite/etiologia , Feminino , Hospitalização/estatística & dados numéricos , Hospitais Universitários/organização & administração , Hospitais Universitários/estatística & dados numéricos , Humanos , Implante de Lente Intraocular/estatística & dados numéricos , Masculino , Admissão do Paciente/estatística & dados numéricos , Facoemulsificação/estatística & dados numéricos , Complicações Pós-Operatórias/epidemiologia , Período Pós-Operatório , Avaliação de Programas e Projetos de Saúde , Estudos Retrospectivos , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/etiologia , Resultado do TratamentoRESUMO
A 49 year-old woman diagnosed with infiltrating lobular breast carcinoma, underwent a right mastectomy and sentinel node biopsy (SLNB). The resected sentinel lymph nodes were negative for malignancy, with an axillary lymphadenectomy not being performed. In the early post-operative period, the patient reported an axillary skin tension sensation, associated with a painful palpable cord. These are typical manifestations of axillary web syndrome (AWS), a poorly known axillary surgery complication, from both invasive and conservative interventions. By presenting this case we want to focus the attention on a pathological condition, for which its incidence may be underestimated by not including it in SLNB studies. It is important for nuclear medicine physicians to be aware of AWS as a more common complication than infection, seroma, or lymphoedema, and to discuss this possible event with the patient who is consenting to the procedure.
Assuntos
Axila , Neoplasias da Mama/patologia , Complicações Pós-Operatórias/etiologia , Biópsia de Linfonodo Sentinela/efeitos adversos , Feminino , Humanos , Pessoa de Meia-Idade , SíndromeRESUMO
INTRODUCTION: Infection by Angiostrongylus cantonensis is caused by eating snails and slugs or contaminated vegetables, and is the commonest cause of eosinophilic meningoencephalitis throughout the world. OBJECTIVES: To make a further study of this condition, analyze the clinical behaviour and evaluate the cerebrospinal fluid findings and response to treatment. PATIENTS AND METHODS: We made a retrospective, descriptive study by reviewing the clinical histories of a series of 17 adult patients attended in two university hospitals in the province of Villa Clara (Cuba), between December 1991 and January 2000. We recorded the characteristics of the clinical picture, results of the complementary investigations, treatment given and clinical course and the necropsy findings of the three patients who died. The data was collected from questionnaires. RESULTS: Headache was a constant symptom. Twelve patients had high temperatures and seven had stiff necks. Motor deficit and coma were seen in the three patients who died. In two patients the cranial nerves were involved. Spinal fluid pleocytosis varied between 48 and 2570 cells/mm3. Initially there was lymphocyte predominance in 10 patients and subsequently eosinophil conversion. The peripheral eosinophilia, seen in all patients, varied between 7% and 61%. Of the 14 patients cured, eight received symptomatic treatment and six antihelminth drugs. Steroids were given to only one patient. Of the three patients who died, two had received antihelminth drugs. CONCLUSIONS: Motor deficit and coma worsen the prognosis, which is generally good. There is no relation between cerebrospinal fluid pleocytosis and raised protein levels in the cerebrospinal fluid, nor between blood eosinophilia and prognosis. The most difficult differential diagnosis in our patients was with leptospirosis. No differences were seen in clinical evolution in relation to the treatment given.
Assuntos
Eosinofilia/epidemiologia , Meningoencefalite/epidemiologia , Adulto , Angiostrongylus cantonensis/imunologia , Angiostrongylus cantonensis/isolamento & purificação , Animais , Anticorpos Monoclonais/imunologia , Área Programática de Saúde , Cuba/epidemiologia , Diagnóstico Diferencial , Ensaio de Imunoadsorção Enzimática , Eosinofilia/complicações , Eosinofilia/parasitologia , Humanos , Imunoglobulina E/imunologia , Leucocitose/líquido cefalorraquidiano , Meningoencefalite/complicações , Meningoencefalite/parasitologia , Transtornos Psicomotores/diagnóstico , Transtornos Psicomotores/etiologia , Infecções por Strongylida/líquido cefalorraquidiano , Infecções por Strongylida/imunologia , Infecções por Strongylida/parasitologia , Inquéritos e QuestionáriosRESUMO
The Companion Animal Parasite Council hosted a meeting to identify quantifiable factors that can influence the prevalence of tick-borne disease agents among dogs in North America. This report summarizes the approach used and the factors identified for further analysis with mathematical models of canine exposure to tick-borne pathogens.
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Doenças do Cão/parasitologia , Doenças Transmitidas por Carrapatos/veterinária , Animais , Cães , Modelos Biológicos , Prevalência , Fatores de Risco , Sociedades Científicas , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/veterinária , Doenças Transmitidas por Carrapatos/epidemiologia , Carrapatos/classificação , Estados Unidos/epidemiologia , Medicina Veterinária/organização & administraçãoRESUMO
Eight polymorphic markers were developed from South African isolates of Ophiostoma quercus. The genome was screened for repeat regions using the fast isolation by amplified fragment length polymorphism of sequences containing repeats protocol and 20 de novo primer pairs flanking putative microsatellite regions were designed. Eight loci were optimized and their polymorphisms evaluated by sequencing. The repeat and flanking regions were highly polymorphic containing both indels and base-pair substitutions revealing a total of 46 alleles in 14 isolates and an average heterozygosity of 0.68. Substantial sequence variability makes these markers useful for genotyping populations in order to calculate diversity and monitor global movement of O. quercus.
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Ten microsatellite markers were developed for the fungus Kirramyces gauchensis, which causes an important stem canker disease of Eucalyptus trees in plantations. Primers for 21 microsatellite regions were designed from cloned fragments. Fourteen of the primer pairs provided single amplicons and 10 of these were polymorphic for K. gauchensis. Allelic diversity ranged from 0.21 to 0.76 with a total of 30 alleles. None of the markers was able to amplify in the phylogenetically distinct but morphologically similar species Kirramyces zuluensis. The 10 characterized polymorphic microsatellite regions will be studied to determine the population structure of K. gauchensis in plantations of different countries.
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Twelve microsatellite markers were developed for population analyses of the fungal pathogen, Dothistroma septosporum. Intersimple sequence repeat polymerase chain reaction (ISSR-PCR) and an enrichment protocol (fast isolation by amplified fragment length polymorphism of sequences containing repeats [FIASCO]) were both used to identify 28 unique microsatellite regions in the genome. From 22 primer pairs designed, 12 were polymorphic. These markers, screened on two populations representing 42 isolates, produced 40 alleles across all loci with an allelic diversity of 0.09-0.76 per locus. Cross-species amplification showed variable success with Dothistroma rhabdoclinis and Mycosphaerella dearnessi and some sequence variation within isolates of Dothistroma pini. These markers will be used to further study the population structure and diversity of D. septosporum.
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The Aldolase multigene family comprises three functional genes (A, B, and C) with tissue-specific expression regulated during ontogeny. DGGE analysis and nucleotide sequencing reveal a family of retropseudogenes of type A in species of MUS: Significant variation in rates of evolution of Aldolase A retropseudogenes is apparent. Our analyses demonstrate that (1) multiple events of retrotransposition are needed to account for the diversity of Aldolase A processed pseudogenes found in mice; (2) some of these sequences have undergone further duplication subsequent to the original retrotransposition event; (3) the patterns of nucleotide substitution are broadly comparable with previous estimates; and (4) estimates of rates of divergence for this array of sequences are up to four times higher than those reported in the literature.
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Frutose-Bifosfato Aldolase/genética , Dados de Sequência Molecular , Pseudogenes/genética , Animais , DNA/química , DNA/genética , Eletroforese/métodos , Evolução Molecular , Duplicação Gênica , Variação Genética , Camundongos , Camundongos Endogâmicos C3H , Filogenia , Análise de Sequência de DNA , Fatores de TempoRESUMO
The genus of subterranean rodents Ctenomys presents the widest range of variability in diploid number among mammals (from 2n = 10 to 2n = 70). In Uruguay, this variability is observed in karyotypes with 2n = 44, 50 or 58 and two geographically isolated populations with 70 chromosomes but different karyotypic structure. The last three populations were analyzed in the present study. They present a satellite DNA, which was isolated from genomic DNA after AluI digestion. In situ hybridization showed that this satellite DNA is located in the centromeric region of a few chromosomes, coincident with Hoechst 33258 staining and C-banding patterns. A similar satellite DNA was detected in Argentinian species of this genus. We established that, in spite of differences in number of positive heterochromatic blocks per karyotype, the C value is the same in the three populations studied. The nature and possible evolutionary path of this repeated DNA is discussed.
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DNA Satélite/genética , Roedores/genética , Animais , Evolução Biológica , Bandeamento Cromossômico , Citogenética , Diploide , Feminino , Genética Populacional , Heterocromatina/genética , Cariotipagem , Masculino , Sequências Repetitivas de Ácido Nucleico , Especificidade da Espécie , UruguaiRESUMO
We analyze evolutionary relationships among members of the family Trypanosomatidae, with particular emphasis on whether protein coding genes support paraphyly of the genus Trypanosoma. Phylogenetic reconstruction based on three different protein coding genes (glyceraldehyde-3-phosphate dehydrogenase, trypanothione reductase, and alpha-tubulin) suggests that Trypanosoma is monophyletic. Moreover, pairwise comparisons of other protein coding genes show that the distances between Trypanosoma cruzi and T. brucei are significantly smaller than are the distances between each Trypanosoma species and Crithidia or Leishmania. These results contradict recent published phylogenies based on nuclear rRNA genes which suggested that T. cruzi is more closely related to Leishmania and Crithidia than to T. brucei.
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Genes de Protozoários , Filogenia , Proteínas de Protozoários/genética , Trypanosoma/genética , Trypanosomatina/genética , Animais , Evolução Biológica , Crithidia/genética , DNA Ribossômico/genética , Gliceraldeído-3-Fosfato Desidrogenases/genética , Humanos , Leishmania/genética , Dados de Sequência Molecular , NADH NADPH Oxirredutases/genética , Trypanosoma/classificação , Trypanosoma brucei brucei/genética , Trypanosoma cruzi/genética , Trypanosomatina/classificação , Tubulina (Proteína)/genéticaRESUMO
BACKGROUND: Two of the major factors affecting the amount of astigmatism correction are the length of the transverse incision and its distance from the center of the cornea. Many nomograms used in clinical practice have been created by varying the length or clear zone diameter of the incisions. A simplification of this situation has been suggested by Thornton, who has theorized that straight transverse incisions, subtending 45 degrees of arc, have equal astigmatic corrective effect at different clear zones. Our study tested Thornton's theory in human donor eyes. METHODS: Ten eyes were tested at four clear zones: 5.0, 6.0, 7.0, and 8.0 mm. Paired straight transverse incisions, subtending an arc of 45 degrees (2.1 to 3.3 mm long), were centered on the 90-degree meridian. Preoperative keratometric readings at the 180- and 90-degree meridians were compared to the postoperative readings; the difference was the total astigmatism induced. We also calculated the coupling ratio. RESULTS: Student's t-tests comparing clear zones 6.0 and 7.0 mm revealed a statistical difference (p = .0085) in total astigmatic induction, greater for the 6.0-millimeter zone. The coupling ratio decreased as the clear zone diameter increased, presumably as a result of diminished flattening effect along the incised meridian. One-way analysis of variance indicated that the groups were different (p = .0001), and that the theory noted above was incorrect. CONCLUSIONS: The effect of transverse incisions subtending the same angular length, drops off dramatically with clear zones larger than 6.0 mm, contrary to the theory of Thornton. This effect may be due to reduction in coupling as the clear zone diameter increases, suggesting that the greatest efficacy is achieved for transverse incisions placed between 5.0- and 6.0-millimeter zones.
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Astigmatismo/etiologia , Córnea/cirurgia , Ceratotomia Radial/efeitos adversos , Ceratotomia Radial/métodos , Cadáver , HumanosRESUMO
Tick-borne disease (TBD) transmission foci need to be characterized in space and time, and are often discontinuous on both scales. An active TBD focus is dependent on the fulfillment of three conditions: tick survival, pathogen survival and opportunities for human exposure. The essentials for tick survival include food sources, reproduction, and protection from environmental extremes. The pathogen survival kit includes sufficient densities of ticks and suitable reservoir hosts, and opportunities for transmission between them in order to maintain infection. Opportunities for human exposure depend on sufficient number of encounters between ticks and humans. Because tick foci need to be described on a range of spatial and temporal resolutions, data for such characterization include a variety of surveillance data, field and laboratory experimental data, as well as results of statistical and mathematical analysis and modeling. The application of new tools from molecular biology, geographic information systems (GIS), and satellite imagery, in conjunction with appropriate analytical methods allow for detection of unknown foci and prediction of new ones. A long-term multi-scale study of Ixodes scapularis and Lyme disease in the north-central U. S. is reviewed. Diverse surveillance methods of ticks, rodents, deer, canids and humans were coupled with environmental characterization in situ to create a habitat profile for Lyme disease ticks. Incorporating various digitized databases, a statistical model was used to develop a risk map for tick distribution in the region. The process of introduction and establishment of new tick foci along the Illinois River is described in relation to the known tick distribution and predictions of invasion based on the risk model.
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Vetores Aracnídeos , Ixodes , Infestações por Carrapato/epidemiologia , Doenças Transmitidas por Carrapatos/epidemiologia , Animais , Vetores Aracnídeos/microbiologia , Vetores Aracnídeos/fisiologia , Reservatórios de Doenças , Previsões , Geografia , Humanos , Illinois/epidemiologia , Sistemas de Informação , Ixodes/microbiologia , Ixodes/fisiologia , Doença de Lyme/epidemiologia , Doença de Lyme/transmissão , Densidade Demográfica , Dinâmica Populacional , Fatores de Risco , Comunicações Via Satélite , Infestações por Carrapato/transmissão , Doenças Transmitidas por Carrapatos/transmissão , CarrapatosRESUMO
The distribution and abundance of Ixodes scapularis were studied in Wisconsin, northern Illinois, and portions of the Upper Peninsula of Michigan by inspecting small mammals for ticks and by collecting questing ticks at 138 locations in state parks and natural areas. Environmental data were gathered at a local level (i.e., micro and meso levels), and a geographic information system (GIS) was used with several digitized coverages of environmental data to create a habitat profile for each site and a grid map for Wisconsin and Illinois. Results showed that the presence and abundance of I. scapularis varied, even when the host population was adequate. Tick presence was positively associated with deciduous, dry to mesic forests and alfisol-type soils of sandy or loam-sand textures overlying sedimentary rock. Tick absence was associated with grasslands, conifer forests, wet to wet/mesic forests, acidic soils of low fertility and a clay soil texture, and Precambrian bedrock. We performed a discriminant analysis to determine environmental differences between positive and negative tick sites and derived a regression equation to examine the probability of I. scapularis presence per grid. Both analyses indicated that soil order and land cover were the dominant contributors to tick presence. We then constructed a risk map indicating suitable habitats within areas where I. scapularis is already established. The risk map also shows areas of high probability the tick will become established if introduced. Thus, this risk analysis has both explanatory power and predictive capability.