Association Between Seasonal Allergic Rhinitis and Air Pollution, Meteorological Factors, and Grass Pollen Counts in Madrid (1996 and 2009).

OBJECTIVE: The aim of this study was to assess the relationship between meteorological and pollution-related variables and the symptoms of patients with seasonal allergic rhinitis due to sensitization to grass pollen during 2 different time periods in Madrid, Spain. METHODS: Between March 23 and December 31 in 1996 and 2009, we carried out a daily count of grass pollen grains (Burkard spore trap) and recorded the rhinitis symptom scores in 2 groups of patients with a history of seasonal allergic rhinitis (n=25 in 1996 and n=23 in 2009). Descriptive statistics of the same variables during the study periods were recorded. Associations between variables were assessed using the paired-samples Wilcoxon test and categorical principal component analysis (CatPCA, SPSS24 package). RESULTS: The mean symptom score was low in 1996 and moderate in 2009. The 1996 and 2009 CatPCA analysis explained around 66.4% and 70.5% of the variance, respectively. The strongest relationships in 1996 were between symptoms and grass pollen counts (R=0.55) and between temperature and ozone (R=0.63). In 2009, the association between temperature and pollution-related variables was even stronger than in 1996 (ozone [R=0.53] and PM10 [R=0.34], with a positive sign in both cases). CONCLUSIONS: The effect of temperature and pollution (mainly ozone, even at lower atmospheric concentrations than in established guidelines for effects on health) may have contributed to the higher seasonal allergic rhinitis symptom score recorded in 2009.

Prevalence of Artemisia species pollinosis in western Poland: impact of climate change on aerobiological trends, 1995-2004.

BACKGROUND: Artemisia species pollen represents a major cause of allergy in Central Europe. Variations in the pollen season, the influence of climate variables and the prevalence of pollinosis to it were analyzed in Poznan, in western Poland between 1995 and 2004. METHODS: A Hirst volumetric spore trap was used for atmospheric sampling. Pollination date trend analysis and Spearman correlation tests were performed. Skin prick tests (SPT) and allergen specific immunoglobulin (lg)E antibody measurements were performed in 676 and 524 patients, respectively. RESULTS: The Artemisia species pollen season grew longer due to a clear advance in the starting day and only a slightly earlier end point; the peak day also came slightly earlier. Rainfall in the first fortnight of July highly influenced pollen season severity. Temperature was directly correlated with daily Artemisia species pollen levels; relative humidity was inversely correlated. Twelve percent of patients had a positive SPT reaction to Artemisia species. Their symptoms were rhinitis and conjunctivitis (15%), atopic dermatitis (15%), chronic urticaria (14.3%), bronchial asthma (2.4%), and facial and disseminated dermatitis (1.3%). Elevated specific IgE concentrations were detected in the sera of 10.1% of patients. CONCLUSIONS: Artemisia species pollen is an important cause of pollinosis in western Poland. Pollen season intensity is highly influenced by rainfall in the previous weeks. Trends towards earlier season starts and longer duration, possibly caused by climate change, may have an impact on the allergic population.

History of allergy in antiquity.

Allergic diseases are not new. They have been described in the early medical literature in various cultures like Egypt, China, indigenous America and in the Greco-Roman tradition. The terms 'idiosyncrasy', 'asthma' and 'eczema' are still in use today. The most famous allergic individual of antiquity with the whole triad of atopic diseases and a positive family history of atopy probably was Emperor Octavianus Augustus.

Landmarks in Allergy during the 19th Century.

There were remarkable achievements in the 19th century in our understanding of the cells of the allergic response, the clear descriptions of hay fever and asthma, as well as the role of pollen in seasonal rhinitis. Although allergy as a concept was not developed until well into the 20th century, the foundations of our present understanding of these diseases were laid in the 1800s. The outstanding physicians and scientists of this time included Paul Ehrlich (who described mast cells, eosinophils and basophils), John Bostock (who provided the first detailed account of hay fever), Charles Blackley (who showed that pollen was the cause of hay fever), Morrill Wyman (who demonstrated that autumnal catarrh was due to ragweed pollen), Henry Hide Salter (who made the first classic description of asthma) and Henri Laënnec (the inventor of the stethoscope).

Milestones in the 20th century.

From its very beginning, the 20th century represented the period of the main breakthrough for allergology as a clinical and scientific entity. The first years of this period were extraordinarily exciting because of the discovery of the anaphylactic reaction in 1902 and its clinical diagnosis as 'local anaphylaxis', 'serum sickness' (1903) or even as 'anaphylactic shock' (1907). The term 'allergy' was coined in 1906 and led to the recognition of allergic diseases as a pathogenetic entity. The first patient organization of hay fever sufferers was founded in Germany in 1900, the same year in which the very first report on immunotherapy was published in New York. In 1911 the era of actual immunotherapy started in London, becoming scientific with the first double-blind study in 1956, and still today being regarded as the backbone of allergology. In 1919 it was shown that allergy could be transferred by blood, in 1921 by serum (Prausnitz-Küstner test) and in 1966 the mystic 'reagins' were recognized as immunoglobulin (Ig) E. The development of the radioallergosorbent test for quantifying specific IgE antibody was a diagnostic landmark for allergists all over the world. The history of allergy diagnosis started with the introduction of a 'functional skin test', named the patch test in 1894. The scratch test was described in 1912 and the patch test in 1931. From 1908 the skin was tested by intracutaneous injections, and from 1930 by a 'puncture test' (a precursor of the prick test) which has been in worldwide use in modified variations since 1959. The rub test ('friction test') was added in 1961. Systematically applied provocation tests started with conjunctival provocation (1907), followed by nasal and bronchial provocation with allergens (1914 and 1925).

Pollen and pollinosis.

Pollen grains only represent a small fraction of the total amount of the viable biological particles present in the air, but pollen are the most important aeroallergens in the outdoor environment. The analysis of pollen has traditionally been carried out by microscopy, which can be traced back to the 17th century. Modern advances in molecular analysis could improve information for allergy sufferers and health care professionals. Pollen allergy (pollinosis) was first described in the 19th century. The prevalence of respiratory diseases increased dramatically during the latter part of the 20th century and millions of individuals are now affected. A number of scientists devised equipment to examine airborne biological particles during the 19th century, but aerobiological monitoring only became standardized during the 20th century. Airborne pollen are routinely monitored in many parts of the world, such as North America and Europe, and the first limited network has also been created for monitoring airborne allergen concentrations. Monitoring of the environment is often based on a combination of measurements and model results. Source-based models can increase our knowledge of airborne pollen because they can explain situations and processes that are almost impossible to understand using observations alone.

New insights into an old story: pollen ROS also play a role in hay fever.

Reactive oxygen species (ROS) can exhibit negative and benign traits. In plants, ROS levels increase markedly during periods of environmental stress, and defense against pathogen attack. ROS form naturally as a by-product of normal oxygen metabolism, and evenly play an essential role in cell growth. The short ROS lifespan makes them ideal molecules to act in cell signaling, a role they share in both plants and animals. A particular plant organism, the pollen grain, may closely interact with human mucosa and an allergic inflammatory response often results. Pollen grain ROS represent a first, crucial signal which primes and magnifies a cascade of events in the allergic response.

The evolution of understanding inhalant allergy.

This article summarizes the developments that led to the current approach to immunotherapy. These developments were characterized in the early years by empirically derived successive approximations to arrive at effective injection regimens, in the middle years by a sorting through of the wide variations in practice with placebo-controlled clinical trials, and more recently by a closer association of clinical and laboratory measures to better define evidence-based practices. The pace of investigation along with the scientific quality continues to increase.