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H S Varonier

Publications and source records attributed to H S Varonier.

At least 19 recordsLinked to original sources
PubMed2004

Influence of MMR-vaccinations and diseases on atopic sensitization and allergic symptoms in Swiss schoolchildren.

The prevalence of asthma and allergic disease has increased in many countries. It has been proposed that vaccinations may contribute to the development of allergic disease by reducing clinical infections in infancy or through the direct IgE-inducing effects of the vaccines. Evidence for a potential role of immunizations in the development of allergic disease is scarce. Therefore the objective was to study the associations between vaccinations against measles, mumps and rubella (MMR), natural infections of these diseases and atopic sensitization to indoor and outdoor allergens and allergic symptoms in schoolchildren. The cross-sectional study including 1537 8(th) grade school children aged 13-15 years living in 10 communities across Switzerland was organized in the framework of an environmental health surveillance program within the School Health Services (Swiss Surveillance Program of Childhood Asthma and Allergies with respect to Air Pollution and Climate, SCARPOL). Main outcome measures were asthma and sneezing during pollen season assessed by parental questionnaires and atopic sensitization determined by IgE concentrations to various allergens. It was found that parents' reported history of measles or mumps was associated with a stronger immune response than two or more vaccinations against the respective infection (measles: geometric mean IgG titers (GMT) lU/ml (95% Cl) 2.8 (2.0-3.9) vs. 1.2 (1.0-1.4), mumps: GMT PE/ml (95% Cl) 16.3 (13.9-19.1) vs. 8.5 (6.1-11.7). With respect to atopic sensitization similar associations for exposure by natural MMR-infections or MMR-vaccinations were found: measles: OR (95% Cl) 1.02 (0.53-1.96) vs. 1.22 (0.69-2.16), mumps: 0.59 (0.38-0.93) vs. 0.79 (0.49-1.27), rubella: 0.93 (0.61-1.43) vs. 0.95 (0.66-1.37), respectively. Inverse relationships were found between the risk of asthma and a positive disease history or vaccination of measles 0.36 (0.14-0.91) vs. 0.45 (0.21-0.98) or a positive serum titer against measles 0.65 (0.35-1.20). From the present study can be concluded that exposure by MMR-vaccinations or natural MMR-infections in childhood does not increase the risk of sensitization to common allergens as well as to allergic respiratory diseases. MMR-vaccinations or natural MMR-infections are therefore an unlikely factor contributing to the increase in atopic disease in developed countries.

Adolescent↗
PubMed2004

No further increase in asthma, hay fever and atopic sensitisation in adolescents living in Switzerland.

Prevalence rates of childhood asthma and allergy have been on the increase for several decades. The present study investigated whether this trend continued during the 1990s in adolescents living in Switzerland. Between 1992 and 2000, the change in prevalence of specific immunoglobulin E to aeroallergens, asthma symptoms and hay fever symptoms assessed by parents' and students' answers to the International Study of Asthma and Allergies in Childhood questions was investigated using three cross-sectional surveys. In total 1,324 (74.9%), 1,668 (80.6%) and 1,250 (73.9%) adolescents participated. Prevalence rates of asthma and current asthmatic symptoms remained constant, irrespective of whether the assessment was based on parental questionnaires or the student's self-completed written or video questionnaires (students' report of current wheeze 8.8, 7.3, and 8.3%). Similarly, no further increase was observed for reported hay fever rates and allergic sensitisation rates (positive multiscreen allergy test, SX1-test: 34.6, 38.9, and 35.6%, respectively). Although time trends in the occurrence of a series of known risk factors were recorded, none of these factors had a significant impact on asthma and allergy prevalence over time. No further increase in asthma and allergy rates occurred during the 1990s in adolescents living in Switzerland. However, to adequately assess the trend a longer period of observation is needed.

Adolescent↗
PubMed1999

Effect of environmental tobacco smoke exposure on respiratory symptoms in children. SCARPOL Team. Swiss Study on Childhood Allergy and Respiratory Symptoms with Respect to Air Pollution, Climate and Pollen.

AIMS: This study determines the prevalence of exposure to environmental tobacco smoke and its relation to respiratory and allergic symptoms among schoolchildren in Switzerland. METHODS: We studied 4470 children aged 6-14 years as part of a multicentre study (SCARPOL study--Swiss Study on Childhood Allergy and Respiratory Symptoms with Respect to Air Pollution, Climate and Pollen) conducted in Switzerland between 1992 and 1993. Environmental tobacco smoke exposure, maternal smoking during pregnancy and respiratory symptoms were assessed by means of a self-administered parental questionnaire. RESULTS: Forty-seven percent of all children were exposed to environmental tobacco smoke. Sixteen percent of the mothers smoked during pregnancy. Children exposed to environmental tobacco smoke at home had an increased risk of respiratory infections (odds ratio (OR) 1.19, 95% confidence intervals (CI) 1.03, 1.37). The risk increased if they were exposed to maternal smoking (OR 1.25, CI 1.06, 1.48) and if the mother also smoked during pregnancy (OR 1.42, CI 1.14, 1.76). Wheezing (OR 1.36, CI 1.03, 1.80) and repeated coughing (OR 1.36, CI 1.14, 1.61) were only associated with maternal smoking. Children exposed to more than 20 cigarettes per day were at highest risk for respiratory problems. CONCLUSION: Almost half of all schoolchildren in Switzerland, especially those from lower socioeconomic classes, are exposed to environmental tobacco smoke. Children with environmental tobacco smoke exposure suffer significantly more often from respiratory symptoms. Maternal smoking during pregnancy additional to current smoking further increases the risk of respiratory morbidity. These findings underline the importance of prevention strategies to reduce the prevalence of smoking and its impact on children's health.

Adolescent↗
PubMed1999

Prevalence of hay fever and allergic sensitization in farmer's children and their peers living in the same rural community. SCARPOL team. Swiss Study on Childhood Allergy and Respiratory Symptoms with Respect to Air Pollution.

INTRODUCTION: Lower prevalence rates of allergic diseases in rural as compared with urban populations have been interpreted as indicating an effect of air pollution. However, little is known about other factors of the rural environment which may determine the development of atopic sensitization and related diseases. OBJECTIVE: The authors tested the hypothesis that children growing up on a farm were less likely to be sensitized to common aerollergens and to suffer from allergic diseases than children living in the same villages but in nonfarming families. MATERIALS AND METHODS: Three age groups of schoolchildren (6-7 years, 9-11 years, 13-15 years) living in three rural communities were included in the analyses. An exhaustive questionnaire was filled in by 1620 (86.0%) parents. A blood sample was provided by 404 (69.3%) of the 13-15 year olds to determine specific IgE antibodies against six common aeroallergens. RESULTS: Farming as parental occupation was reported for 307 children (19.0%). After adjustment for potential covariates such as family history of asthma and allergies, parental education, number of siblings, maternal smoking, pet ownership, indoor humidity and heating fuels, farming as parental occupation was significantly associated with lower rates of sneezing attacks during pollen season (adjusted OR 0.34, 95% CI 0.12-0.89) and atopic sensitization (adjusted OR 0.31, 95% CI 0.13-0.73) whereas the association with wheeze (adjusted OR 0.77 95% CI 0.38-1.58) and itchy skin rash (adjusted OR 0.86, 95% CI 0.49-1.50) was not statistically significant. The risk of atopic sensitization was lower in children from full-time farmers (adjusted OR 0.24, 95% CI 0.09-0.66) than from part-time farmers (adjusted OR 0.54, 95% CI 0.15-1.96). CONCLUSION: Factors directly or indirectly related to farming as parental occupation decrease the risk of children becoming atopic and developing symptoms of allergic rhinitis.

Adolescent↗
PubMed1998

Comparison of responses to an asthma symptom questionnaire (ISAAC core questions) completed by adolescents and their parents. SCARPOL-Team. Swiss Study on Childhood Allergy and Respiratory Symptoms with respect to Air Pollution.

The primary objective of the study was to determine the impact of the identity of the respondent (parents versus adolescents) on prevalence estimates of asthma symptoms in Swiss adolescents. In addition, factors influencing agreement between parents' and adolescents' responses to the same questions were analysed. One thousand three hundred and seventy-four (78.4%) adolescents, aged 14 years, self-completed a questionnaire at school based on the International Study of Asthma and Allergy in Childhood (ISAAC) core questions on wheezing and asthma. The same questions were incorporated into a questionnaire to be completed by the parents at home. The adolescents' self-reported prevalence rates of current asthma symptoms and "asthma ever" were significantly higher than those obtained from the parental questionnaires. 856 (62.6%) parental questionnaires were filled in by parents without the help of the adolescents, 460 (37.4%) were completed by parents and adolescents and 51 (3.7%) were completed by the adolescents without the parents. Prevalence rates were higher when parents and adolescents completed the questionnaire jointly than when questionnaires were completed by parents alone. The level of agreement between parental and self-completed questionnaires was moderate to low (kappa coefficients 0.22-0.68). Agreement between parental and adolescents reports of asthma symptoms was best when questionnaires were completed jointly by parents and adolescents, when the adolescent was a girl, when a family history of asthma was recorded, when the adolescent was a non-smoker, and when the parental education was high. We conclude that the higher reporting of prevalence rates of current asthma symptoms by adolescents compared to reporting by their parents demonstrates the need to take the respondent to a questionnaire into account when comparisons are made between prevalence studies. The results also suggest that factors related to the family milieu influence symptom reporting.

Adolescent↗
PubMed1997

Validation of a rhinitis symptom questionnaire (ISAAC core questions) in a population of Swiss school children visiting the school health services. SCARPOL-team. Swiss Study on Childhood Allergy and Respiratory Symptom with respect to Air Pollution and Climate. International Study of Asthma and Allergies in Childhood.

UNLABELLED: The primary aim of the study was to assess the validity of the ISAAC core questions on rhinitis in a population of Swiss school children by comparing them to skin prick test results. Second, the positive predictive value in detecting atopy among children with rhinitis symptoms was determined. Third, agreement between parental reports of hay fever and rhinitis symptoms was evaluated, since earlier Swiss prevalence surveys had exclusively relied on reported hay fever. MATERIAL AND METHODS: Two thousand nine hundred and fifty-four (81.2%) parents of 7, 10 and 14-year old children filled in an exhaustive questionnaire which included the ISAAC core questions on rhinitis. Two thousand one hundred and twenty children also underwent skin prick testing against six common aeroallergens (grass mixture, birch, mugwort, D. pteronyssinus, cat and dog dander). The analysis is restricted to children with both questionnaire data and skin prick test results. RESULTS: Sensitization to any allergen was most strongly associated with reported hay fever (OR = 5.7, 95% CI 4.4-7.4), nose problems accompanied by itchy-watery eyes (OR = 4.4, 95% CI: 3.3-5.7), symptoms occurring only during pollen season (March through September) (OR = 4.9, 95% CI: 3.6-6.5) and a combination of these latter two symptoms (OR = 5.8, 95% CI: 4.1-8.1). The association was stronger for a sensitization to outdoor allergens than for indoor allergens. The specificity of the various questions was high, ranging from 77.5% to 97.6%, but the sensitivity was low (2.6% to 42.7%). The positive predictive value for atopy among children with symptoms was 63% for sneezing accompanied by itchy-watery eyes, 67% for symptoms occurring only during the pollen season and 70% for reported hay fever. However, agreement between reported rhinitis symptoms and hay fever was only moderate. About one third of the children with symptoms indicative of seasonal rhinitis did not report the label "hay fever". CONCLUSIONS: We conclude from our analyses that the ISAAC core questions on rhinitis are highly specific and therefore useful in excluding atopy. In addition they have a high positive predictive value in detecting atopy among children with symptoms, but they are not helpful for detecting atopy in a general population of children (low sensitivity). To monitor time trends in the prevalence of allergic rhinitis in Switzerland, questions on rhinitis symptoms as well as on the diagnostic label "hay fever" have to be included in a questionnaire because they contain complementary information since under-diagnosis of allergic rhinitis is common.

Adolescent↗
PubMed1997

Respiratory health and long-term exposure to air pollutants in Swiss schoolchildren. SCARPOL Team. Swiss Study on Childhood Allergy and Respiratory Symptoms with Respect to Air Pollution, Climate and Pollen.

The impact of long-term exposure to air pollution on respiratory and allergic symptoms and illnesses was assessed in a cross-sectional study of schoolchildren (ages 6 to 15 yr, n = 4,470) living in 10 different communities in Switzerland. Air pollution measurements (particulate matter less than 10 microns in diameter [PM10], nitrogen dioxide [NO2], sulfur dioxide [SO2], and ozone) and meteorologic data were collected in each community. Reported symptom rates of chronic cough, nocturnal dry cough, and bronchitis, adjusted for individual risk factors, were positively associated with PM10, NO2, and SO2. The strongest relationship was observed for PM10 (adjusted odds ratios for chronic cough, nocturnal dry cough, and bronchitis between the most and the least polluted community for PM10 were 3.07 [95% CI: 1.62 to 5.81], 2.88 [95% CI: 1.69 to 4.89], and 2.17 [95% CI: 1.21 to 4.89], respectively). The high correlation between the average concentrations of the pollutants makes the assessment of the relative importance of each pollutant difficult. No association between long-term exposure to air pollution and classic asthmatic and allergic symptoms and illnesses was found. There was some indication that frequency of fog is a risk factor of chronic cough and bronchitis, independent of air pollution. In conclusion, this study provides further evidence that rates of respiratory illnesses and symptoms among children augment with increasing levels of air pollution even in countries like Switzerland with moderate average air pollution concentrations.

Adolescent↗
PubMed1991

Cord serum IgE and early detection of the atopic phenotype: suitable for routine screening?

Cord serum IgE has been shown to be a valuable marker for the prediction of atopy. Our study was designed to verify these findings for possible systematic screening recommendation. Our study consisted of 338 children who were followed from birth to 18 months. Cord serum IgE was measured by paper immunosorbent test and radioimmunoassay. All other data (sex, family history and environment, diet, occurrence of atopic manifestations) were recorded. Of the 338 children, 118 (34.9%) developed obvious clinical symptoms of atopy during the study period. Using the receiver operator curve we found an IgE level of 1.20 IU/ml to be the best cut-off point as a predictor of atopy with 95% specificity but 13% sensitivity. Combination with other predictors such as sex, family history, environmental factors and diet did not increase the predictive value of the test. Because of this low sensitivity we conclude that cord serum IgE is insufficient to detect individuals at risk for atopy even if associated with genetic and environmental factors. Thus it should not be recommended for routine screening purposes; more sensitive markers are needed.

Dermatitis, Atopic↗
PubMed1984

[Prevalence of allergies in children and adolescents].

As for other chronic diseases, surveys of allergic conditions can give useful data about their prevalence and natural history. A study of the frequency of major allergic manifestations--asthma, allergic rhinitis, hay fever, atopic dermatitis and urticaria--could be performed twice at 13 years interval (1968/1981) among kindergarten children (4-6 years old) and 9th grade students (15 years old) attending the Geneva public schools. These samples represent about 90% of the corresponding age groups of the total population. Both surveys were conducted with individual interviews and physical examinations by trained physicians and nurses. The total prevalence of allergy was 5.4% in 1968 and 7.0% in 1981 for the children, and 10.3% and 11.5% for the adolescents. Asthma prevalence was 1.7% in 1968 vs 2.0% in 1981 among children, and 1.9% vs 2.8% among adolescents. For the other diseases the figures are: allergic rhinitis 0.6% vs 0.2% and 1.0% vs 0.6%; hay fever 0.5% vs 1.1% and 4.4% vs 6.1%; atopic dermatitis 2.2% vs 2.8% and 2.3% vs 1.5%; urticaria 0.4% vs 0.9% and 0.7% vs 0.5%. The rate increases over the years concern mainly the documented respiratory manifestations of atopy. Variables like sex, family atopy, ethnic origin and socio-economic status seem to be important factors influencing prevalence. Environmental factors may explain the increase of allergy in childhood and adolescence.

Adolescent↗
PubMed1977

HLA antigens in grass pollinosis.

48 patients with grass pollinosis and strongly positive skin tests to crude timothy pollen extract, as well as the relatives of 11 of the, were typed for 26 HLA antigens of the A and B loci. No significant alteration in the frequencies of any particular antigen was observed, except for an increase of HLA-A1 and B8 in patients with multiple manifestations of reaginic disease. In the 11 families investigated, susceptibility to grass pollinosis and IgE levels did not appear to be linked to HLA haplotypes. Preliminary studies with anti-lymphocyte B sera did not reveal any significant alteration in the frequency of positive reactions, using enriched population of B lymphocytes from 16 patients.

Cytotoxicity Tests, Immunologic↗
PubMed1976

[Peak expiratory flow rate among Swiss boys and girls between 4 to 19 1/2 years of age domiciled in the Canton of Geneva in 1972].

Peak expiratory flow rate (PEFR) was measured by means of a Wright peak flow meter on a sample of 2865 boys and 2712 girls selected at random in the Canton of Geneva, Switzerland (resident population of Swiss children and adolescents aged 4-19 1/2 in 1972). Technique of measurements and statistical analysis are described with an aim at standardization. Expected percentiles of PEFR (50, 25, 10 and 2.5) versus standing height are presented in tabular form for boys and girls separately. Nomograms are given allowing graphical determination of expected PEFR percentiles in either sex for any given standing height.

Adolescent↗