Recent Understandings of Pet Allergies

Environmental risk factors for respiratory infection and wheeze in young children: A multicentre birth cohort study

INTRODUCTION

Respiratory infections and wheeze have a considerable impact on the health of young children and consume significant healthcare resources. We aimed to evaluate the effect of environmental factors on respiratory infections and symptoms in early childhood.

METHODS

Environmental risk factors including: daycare attendance; breastfeeding; siblings; damp within the home; environmental tobacco smoke (ETS); child's bedroom flooring; animal exposure; road traffic density around child's home; and solid fuel pollution within home were assessed in children recruited to the GO-CHILD multicentre prospective birth cohort study. Follow-up information on respiratory infections (bronchiolitis, pneumonia, otitis media and cold or flu), wheeze and cough symptoms, healthcare utilisation and medication prescription was collected by postal questionnaires at 12 and 24 months. Log binomial and ordered logistic regression models were fitted to the data.

RESULTS

Follow-up was obtained on 1344 children. Daycare was associated with increased odds of pneumonia (odds ratio [OR] = 2.39, 95% confidence interval [CI]: 1.04-5.49), bronchiolitis (OR = 1.40, 1.02-1.90), otitis media (OR = 1.68, 1.32-2.14) and emergency department attendance for wheeze (RR = 1.81, 1.17-2.80). Breastfeeding beyond 6 months was associated with a reduced odds of bronchiolitis (OR = 0.55, 0.39-0.77) and otitis media (OR = 0.75, 0.59-0.99). Siblings at home was associated with an increased odds of bronchiolitis (OR = 1.65, 1.18-2.32) and risk of reliever inhaler prescription (RR = 1.37, 1.02-1.85). Visible damp was associated with an increased odds of wheeze (OR = 1.85, 1.11-3.19), and risk of reliever inhaler (RR = 1.73, 1.04-2.89) and inhaled corticosteroid prescription (RR = 2.61, 1.03-6.59). ETS exposure was associated with an increased odds of primary care attendance for cough or wheeze (OR = 1.52, 1.11-2.08). Dense traffic around the child's home was associated with an increased odds of bronchiolitis (OR = 1.32, 1.08-2.29).

CONCLUSION

Environmental factors likely influence the wide variation in infection frequency and symptoms observed in early childhood. Larger population studies are necessary to further inform and guide public health policy to decrease the burden of respiratory infections and wheeze in young children.

[Are pets, dog or cat, a risk or a protector factor for the development or exacerbation of asthma? Systematic review of systematic reviews]

BACKGROUND

Preliminary studies have shown conflicting results on the association between exposure to pets (cat or dog) and asthma. Previous scientific evidence has not been clear to determine if avoiding or allowing the exposure to pets could prevent, improve, or worsen the development of asthma and its symptoms.

OBJECTIVE

To try to explain the controversial relationship between exposure to pets (dog or cat) and its effect on the development of asthma or the exacerbation of symptoms in both children and adults.

METHODS

A standardized search in five electronic databases by an independent reviewer was carried out. The final sample of studies included in the overview of systematic reviews was screened and synthesized through a master table. A narrative description of the results was made.

RESULTS

This systematic review of systematic found determined principally that having a cat could be a risk factor and having a dog a protective factor in the development of asthma. However, early exposure to both cats and dogs (before the age of two) reduces the probability of asthma symptoms and wheezing in the school years. Additionally, having antecedents of sensibilization to pets allergen could be a risk factor to exacerbate asthma in both children and adults.

BORN TO WHEEZE OR LEARNED WHEN WE WERE YOUNG: MATERNAL AND ENVIRONMENTAL FACTORS INFLUENCE ATOPIC RISK

The prevalence of atopic diseases is increasing globally, particularly in children. Heritable genetics can partially explain risk of disease. Evidence also points to acquired genetic material, in the form of the microbiome, as an important factor in disease pathogenesis. The acquisition of the microbiome dynamically changes in response to differences in lifestyle and environmental factors. Also, in utero, maternal and environmental factors influence atopic risk for allergic rhinitis, eczema, asthma, and food allergy. Combining the analytical power of omics, we focus on how the microbiota mediates effects between mother, environment, immunity, and risk of atopic disease. In parallel, we stress that health care disparities impact asthma morbidity and mortality. Efforts to improve asthma outcomes must include multidisciplinary strategies.

Immunogenicity of a new allergoid from Felis domesticus

BACKGROUND

The chemical modification of allergens with glutaraldehyde improves safety while maintaining clinical efficacy, which permits the administration of higher doses of immunotherapy, reducing the risk of adverse reactions. The aim of this study is to evaluate the immunogenic capacity of a new cat dander polymer by immunizing mice and quantifying immunoglobulins in serum, in comparison with the non-modified allergen.

METHODS

The study consists of the immunization of three mice groups with the polymerized and the native extract, together with a negative control group. The immunoglobulin levels in serum have been measured by indirect ELISA. By means of the non-parametric Mann-Whitney U test, it was determined if there were significant differences in the values of specific antibodies between groups.

RESULTS

The group immunized with the allergoid showed significantly higher specific IgG and IgG1 values to dander allergens and specific IgG to the major allergen Fel d 1, while there were no significant changes in IgG2a and IgE values. These results could be due to a higher immunization dose. The vaccine formulation was based on the optimal defined dose for clinical efficacy of allergen immunotherapy.

CONCLUSIONS

This preclinical study carried out with the present assay has established that the allergoid of cat dander extract, as designed for its optimal use in allergen immunotherapy, produces a higher specific IgG than the native extract, in addition to showing significantly higher specific IgG1 levels, evidencing a greater effectiveness in immunization.

Best Practice Standards in Animal-Assisted Interventions: How the LEAD Risk Assessment Tool Can Help

Simple Summary

Animal-assisted interventions (AAI) in educational and other settings have steadily increased over the last fifty years. While scientific research on the effects of AAI is still growing, the application in the field has overtaken the science and seen a steep rise in many countries and settings in recent years. Surprisingly, while different organisations provide a range of guidelines, no unified, standardised guidelines exist, nor do easy-to-use risk assessment tools for AAI providers and users exist. With differences in practical application and different policies used by AAI providers worldwide, this means that in practice AAI takes place in an unregulated manner without a gold standard of best practice. To ensure safe AAI worldwide, we provide urgently needed unified guidelines on best practice in relation to risk assessment, safeguarding and animal welfare priorities. We also provide the first comprehensive risk assessment and animal welfare tools to achieve consistent welfare and safety standards for best practice across educational and other settings around the world.

Abstract

Animal-assisted interventions (AAI) in educational and other settings have steadily increased over the last fifty years and a steep rise in AAI has been observed in many countries and settings in recent years. Surprisingly, while different providers and organisations provide a range of guidelines, no unified, standardised guidelines or risk assessment tools for AAI exist. This means that in practice AAI takes place in an unregulated manner and without a gold standard of best practice. In addition, knowledge of which interventions are effective is still scarce and the mechanisms of successful interventions are not yet fully understood. This is partly due to AAI being a relatively new research field and standards of research and practice have often lacked rigour in the past. Furthermore, knowledge and experience of providers undertaking interventions varies greatly as there is no standardised training either. We address the striking lack of standardised guidelines and procedures. In all AAI, high importance should be placed on safety and welfare of all involved. Children and other AAI participants, staff and animals should be given equal consideration when assessing risks and welfare needs. To ensure safe AAI worldwide, we provide urgently needed guidelines on best practice in relation to risk assessment, safeguarding and animal welfare priorities. The guidelines were developed for a large-scale longitudinal, randomised controlled trial AAI project and are relevant to AAIs within educational and other settings. We also provide the first set of comprehensive risk assessment and animal welfare tools to achieve consistent welfare and safety standards for best practice across educational and other settings around the world.

Early exposure to cats, dogs and farm animals and the risk of childhood asthma and allergy

BACKGROUND

Synergistic role of exposure to cats, dogs, and farm animals during infancy on the risk of childhood asthma and allergy remains unknown.

OBJECTIVES

To investigate independent and synergistic associations between exposure to indoor pets and farm animals during infancy and the risk of asthma and allergy by age 5.

METHODS

We studied 3781 children participating in the Finnish Type 1 Diabetes Prediction and Prevention (DIPP) Nutrition Study. At age 5, a validated version of the International Study of Asthma and Allergies in Childhood questionnaire was administered to collect information on asthma and allergic disease, and exposure to indoor pets and farm animals during the first year of life. Allergen-specific IgE antibodies were analyzed from serum samples. Statistical analyses employed Cox proportional hazards and logistic regression.

RESULTS

Having a dog in the house was inversely associated with the risk of asthma (HR 0.60; 95% CI, 0.38-0.96), allergic rhinitis (OR 0.72; 95% CI, 0.53-0.97), and atopic sensitization (OR 0.77; 95% CI, 0.63-0.96). Having a cat was associated with a decreased risk of atopic eczema (OR 0.68; 95% CI, 0.51-0.92). Farm animals were neither independently nor in synergy with indoor pets associated with the outcomes.

CONCLUSION

Having a dog or cat in the house during the first year of life may protect against childhood asthma and allergy. We did not find a synergistic association between cat, dog, and farm animal exposure on the risk of childhood asthma and allergy. Future research should identify specific causative exposures conferred by indoor pets and whether they could be recommended for allergy prevention.

Spotlight on the psychological basis of childhood pet attachment and its implications

Research suggests that humans can form strong attachments to their pets, and at least some pets display attachment behaviors toward their human caretakers. In some cases, these bonds have been found to support or enhance the physical and emotional well-being of both species. Most human–animal interaction research to date has focused on adult owners, and therefore less is known about childhood pet attachment. However, there is growing evidence that pets may play an important role in the development and well-being of children, as well as adult family members. Research conducted to date suggests that child–pet relationships may be especially impactful for children who do not have stable or secure attachments to their human caretakers. However, given that human–animal interactions, including pet ownership, can also introduce some risks, there is considerable value in understanding the nature of child–pet attachments, including the potential benefits of these relationships, from a scientific perspective. The purpose of this review is to provide background and a brief overview of the research that has been conducted on childhood attachment to pets, as well as to identify areas where more research would be beneficial.

Validation of PROTIA™ Allergy-Q 64 Atopy® as a Specific IgE Measurement Assay for 10 Major Allergen Components

PURPOSE

Component-resolved diagnostics (CRD) is expected to provide additional diagnostic information in allergic patients. PROTIA™ Allergy-Q 64 Atopy®, a recently developed CRD-based multiplex specific immunoglobulin E (sIgE) assay, can quantitatively measure sIgE to major allergen components.

METHODS

The sIgE detection by PROTIA™ Allergy-Q 64 Atopy® and ImmunoCAP® assays was compared using the sera of 125 Korean allergic patients. Group 1 and 2 allergens of house dust mites (HDMs; Dermatophagoides farinae (Der f) 1 and Der f 2 in PROTIA™ Allergy-Q 64 Atopy®, Dermatophagoides pteronyssinus (Der p) 1 and Der p 2 in ImmunoCAP®), Bet v 1, Fel d 1, Que a 1, ω-5 gliadin, α-lactalbumin, β-lactoglobulin, casein and α-Gal were measured by both assays.

RESULTS

Comparing the results from the 2 assays, the agreement rate for all the 10 allergens was > 88% (group 1 HDM allergen, 100%; group 2 HDM allergen, 94.6%; Bet v 1, 97.4%; Fel d 1, 90.5%; Que a 1, 89.2%; α-lactalbumin, 96%; β-lactoglobulin, 88%; casein, 88%; ω-5 gliadin, 96%; α-Gal, 100%). Correlation analysis indicated that, all the 10 allergen sIgEs showed more than moderate positive correlation (Pearson correlation coefficients > 0.640). Additionally, intra-class comparison showed more than high correlation for all the 10 allergens (Spearman's rank correlation coefficients > 0.743).

CONCLUSIONS

PROTIA™ Allergy-Q 64 Atopy® is reliable and comparable to the ImmunoCAP® assay for component-resolved diagnosis.

Does evidence support the use of cat allergen immunotherapy?

PURPOSE OF REVIEW

Cat allergy can manifest as allergic rhinitis, conjunctivitis and/or asthma. With widespread cat ownership and exposure, cat allergy has emerged as a major cause of morbidity. Cat allergen immunotherapy is a potential disease modifying treatment for patients with cat allergy. We examine evidence on the effectiveness, cost-effectiveness and safety of cat allergen immunotherapy and consider the clinical contexts in which it should be prescribed.

RECENT FINDINGS

The European Association of Allergy and Clinical Immunology systematic reviews on allergic rhinitis and asthma along with the accompanying guidelines on allergic rhinitis were used as primary sources of evidence. Subcutaneous immunotherapy (SCIT) and sublingual immunotherapy (SLIT) are most common routes of administration for allergen immunotherapy (AIT). A limited number of high-quality studies related to cat dander have shown mixed results in improvements in ocular and nasal symptoms, asthma symptoms, peak expiratory flow rate and medication use scores with subcutaneous immunotherapy. Two studies examining cat dander and cat-related allergy response with sublingual immunotherapy have shown mixed results in terms of symptomatic response. One randomized trial examining intralymphatic immunotherapy has shown a positive symptom response and a favourable safety profile. Although studies have reported mixed results regarding safety of SCIT, adverse events have been reported more commonly with SCIT than SLIT.

SUMMARY

There is a limited body of high-quality evidence on the effectiveness and safety of cat AIT and no high-quality data on its cost-effectiveness. The available evidence on effectiveness is mixed based on studying a limited array of immunological, physiological and patient-reported outcome measures. Based on this evidence and extrapolating on the wider evidence base in AIT, it is likely that some patients may benefit from this modality of treatment, particularly those with moderate-to-severe disease who are inadequately controlled on allergen avoidance measures and pharmacotherapy and those who are monosensitized to Felix Domesticus 1. Further evidence is, however, required from larger trials before more definitive advice can be offered.

Bedroom Allergen Exposure Beyond House Dust Mites

PURPOSE OF REVIEW

The review provides insight into recent findings on bedroom allergen exposures, primarily focusing on pet, pest, and fungal exposures.

RECENT FINDINGS

Large-scale studies and improved exposure assessment technologies, including measurement of airborne allergens and of multiple allergens simultaneously, have extended our understanding of indoor allergen exposures and their impact on allergic disease. Practical, streamlined methods for exposure reduction have shown promise in some settings, and potential protective effects of early-life exposures have been further elucidated through the investigation of specific bacterial taxa. Advances in molecular allergology have yielded novel data on sensitization profiles and cross-reactivity. The role of indoor allergen exposures in allergic disease is complex and remains incompletely understood. Advancing our knowledge of various co-exposures, including the environmental and host microbiome, that interact with allergens in early life will be crucial for the development of efficacious interventions to reduce the substantial economic and social burden of allergic diseases including asthma.