What attracts elk onto cattle pasture? Implications for inter-species disease transmission.

In Southwest Alberta, beef cattle and wild elk (Cervus elaphus) have similar habitat preferences. Understanding their inter-species contact structure is important for assessing the risk of pathogen transmission between them. These spatio-temporal patterns of interactions are shaped, in part, by range management and environmental factors affecting elk distribution. In this study, resource selection modeling was used to identify factors influencing elk presence on cattle pasture and elk selection of foraging patches; furthermore, consequences for inter-species disease transmission were discussed. Data on pasture management practices and observations of elk were collected from 15 ranchers during interviews. Pasture use by elk was defined based on telemetry data (from GPS collars deployed on 168 elk in 7 herds) and rancher observations. At the patch scale, foraging patches used by elk were identified by spatio-temporal cluster analysis of telemetry data, whereas available patches were randomly generated outside the area delimited by used patches. For pastures and patches, landscape and human-managed features were characterized using remote sensing data and interviews, respectively. Attributes of available and used pastures (or patches) were compared using resource selection functions, on annual and seasonal (or annual and monthly) time scales. Additionally, intensity of pasture use was modeled using negative binomial regression. Cultivated hay land and mineral supplements were associated with elk presence on cattle pastures, whereas pastures with manure fertilization and higher traffic-weighted road densities were less likely to be used by elk. The effects of landscape (elevation, aspect, water access) and vegetation (forest cover, Normalized Difference Vegetation Index) characteristics on patch selection were consistent with typical elk habitat requirements. The presence of cattle and the traffic-weighted road density were negatively associated with patch selection. The apparent avoidance of cattle by elk reduced the risk of direct transmission of pathogens, except during winter months. However, human-managed features attracting elk to cattle pastures (e.g. hay land and mineral supplements) may increase inter-species pathogen transmission through indirect contacts.

The contribution of sublingual immunotherapy to the achievement of control in birch-related mild persistent asthma: A real-life randomised trial

Background: Asthma control represents the main goal of asthma management and different strategies aim to avoid the long term downsides of inhaled corticosteroids. We investigated in real-life conditions the contribution of sublingual immunotherapy in achieving the control of birch-related mild persistent asthma compared to two usual step-up therapeutic options. Methods: A three-year open randomised study included 84 asthmatics, uncontrolled during the previous birch pollen season, despite a treatment with budesonide 400 μg/day. Patients randomly received budesonide 800 μg/day, budesonide 1600 μg/day, budesonide 400 μg/day plus montelukast 10 μg/day and budesonide 400 μg/day plus carbamylated allergoid of betulaceae pre-coseasonally. Asthma Control test, combined allergy symptoms and medications score, albuterol consumption, lung function, nasal eosinophils and nasal steroids usage were assessed as changes from the first to last pollen season. Result: Seventy-six patients concluded the study. All options, except budesonide 800 μg/day, produced an improvement of mean monthly Asthma Control test (p < 0.05). Patients undergoing low-dose budesonide plus immunotherapy achieved, after three years, an appreciable control (ACT mean score 24). A significant improvement was seen in all groups for allergy symptoms plus medications and bronchial reactivity. Albuterol consumption and lung function improved in all but the first group. Only budesonide plus immunotherapy reduced nasal eosinophils and nasal steroids usage. Two mild self-resolving adverse events were reported. Conclusions: For patients with respiratory allergy due to birch pollen and mild persistent asthma, sublingual immunotherapy added to low-dose inhaled corticosteroids appears effective in maintaining long-term seasonal asthma control, representing a safe opportunity to reduce the cumulative amount of delivered corticosteroids (AU)

The contribution of sublingual immunotherapy to the achievement of control in birch-related mild persistent asthma: a real-life randomised trial.

BACKGROUND: Asthma control represents the main goal of asthma management and different strategies aim to avoid the long term downsides of inhaled corticosteroids. We investigated in real-life conditions the contribution of sublingual immunotherapy in achieving the control of birch-related mild persistent asthma compared to two usual step-up therapeutic options. METHODS: A three-year open randomised study included 84 asthmatics, uncontrolled during the previous birch pollen season, despite a treatment with budesonide 400µg/day. Patients randomly received budesonide 800µg/day, budesonide 1600µg/day, budesonide 400µg/day plus montelukast 10µg/day and budesonide 400µg/day plus carbamylated allergoid of betulaceae pre-coseasonally. Asthma Control test, combined allergy symptoms and medications score, albuterol consumption, lung function, nasal eosinophils and nasal steroids usage were assessed as changes from the first to last pollen season. RESULT: Seventy-six patients concluded the study. All options, except budesonide 800µg/day, produced an improvement of mean monthly Asthma Control test (p<0.05). Patients undergoing low-dose budesonide plus immunotherapy achieved, after three years, an appreciable control (ACT mean score 24). A significant improvement was seen in all groups for allergy symptoms plus medications and bronchial reactivity. Albuterol consumption and lung function improved in all but the first group. Only budesonide plus immunotherapy reduced nasal eosinophils and nasal steroids usage. Two mild self-resolving adverse events were reported. CONCLUSIONS: For patients with respiratory allergy due to birch pollen and mild persistent asthma, sublingual immunotherapy added to low-dose inhaled corticosteroids appears effective in maintaining long-term seasonal asthma control, representing a safe opportunity to reduce the cumulative amount of delivered corticosteroids.

The type of sensitizing allergen can affect the evolution of respiratory allergy.

BACKGROUND: Numerous factors affect the evolution of respiratory allergy, in children, but little is known in adults. We assessed in a prospective study the influence of the type of allergen on the progression of disease. METHODS: Outpatients, with respiratory allergy underwent skin tests and pulmonary function/methacholine challenge at baseline and after 3 years. Patients were subdivided in pure rhinitis or rhinitis + bronchial hyperreactivity (BHR). In polysensitized subjects a single relevant allergen (mites, grasses, birch, Parietaria) was identified based on symptom distribution and when needed on nasal challenge. RESULTS: 6750 patients (age range 12-46) were studied. Of them, 17.8% were monosensitized but this percentage decreased to 10.4% after 3 years (P < 0.05). Subjects with pure rhinitis were 81% at the beginning and 48% at the end. After 3 years, the patients with bronchial responsiveness increased from 18% to 58% for mites, 22% to 49% for birch, 18% to 44% for grasses, 17% to 32% for Parietaria, with a significant difference among allergens (P < 0.05). Almost the same was seen in monosensitized subjects, being mites most likely to cause a worsening. All patients with BHR at baseline received immunotherapy. In these patients the onset of new sensitizations was significantly lower than in the group (pure rhinitis) receiving drugs only and lower airways symptoms disappeared more frequently. CONCLUSION: The different type of allergen influences the course of the disease, as well as the use of immunotherapy.

Sublingual immunotherapy in the context of a clinical practice improvement program in the allergological setting: results of a long-term observational study.

The aim of this study was to assess the efficacy and safety of sublingual immunotherapy (SLIT) in a Clinical Practice Improvement (CPI) program carried out in allergology. The study was conducted between 1992 and 2001 using an observational type methodology in line with standard clinical practice. The program consisted of 4 basic steps: setting up of a decision-making tree; standardization of main diagnostic and therapeutic aspects; data collection; definition and evaluation of main clinical endpoints. Study patients were screened among 1508 patients with pollen and/or dust mite respiratory allergy, 350 of which, one year after having experienced a pharmacological treatment failure, were administered immunotherapy by injection (n = 111) or alternative route (n = 239). For each one of the three immunotherapy treatment groups (nasal, SLIT or injective) there was a control group of patients who, despite their poor response to pharmacological treatment, continued with pharmacological therapy alone (n = 314 in total; 68, 192 and 54 respectively). The observation of 130 SLIT patients, 106 of which were treated for at least 36 months, towards the control group evidenced that such therapy, apart from resulting efficient and particularly safe, has an unfailing protective effect against the development of asthma and new allergic sensitizations.