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Asthma often starts before six years of age. However, there remains uncertainty as to when and how a preschool-age child with symptoms suggestive of asthma can be diagnosed with this condition. This delays treatment and contributes to both short- and long-term morbidity. Members of the Canadian Thoracic Society Asthma Clinical Assembly partnered with the Canadian Paediatric Society to develop a joint working group with the mandate to develop a position paper on the diagnosis and management of asthma in preschoolers. In the absence of lung function tests, the diagnosis of asthma should be considered in children one to five years of age with frequent (≥8 days/month) asthma-like symptoms or recurrent (≥2) exacerbations (episodes with asthma-like signs). The diagnosis requires the objective document of signs or convincing parent-reported symptoms of airflow obstruction (improvement in these signs or symptoms with asthma therapy), and no clinical suspicion of an alternative diagnosis. The characteristic feature of airflow obstruction is wheezing, commonly accompanied by difficulty breathing and cough. Reversibility with asthma medications is defined as direct observation of improvement with short-acting ß2-agonists (SABA) (with or without oral corticosteroids) by a trained health care practitioner during an acute exacerbation (preferred method). However, in children with no wheezing (or other signs of airflow obstruction) on presentation, reversibility may be determined by convincing parental report of a symptomatic response to a three-month therapeutic trial of a medium dose of inhaled corticosteroids with as-needed SABA (alternative method), or as-needed SABA alone (weaker alternative method). The authors provide key messages regarding in whom to consider the diagnosis, terms to be abandoned, when to refer to an asthma specialist and the initial management strategy. Finally, dissemination plans and priority areas for research are identified.

Pneumococcal diseases are a major public-health problem all over the world. The etiological agent, Streptococcus pneumoniae (the pneumococcus) in surrounded by a polysaccharide capsule. Differences in the composition of this capsule permit the serological differentiation between about 90 capsular types, some of which are frequently associated with pneumococcal disease, others rarely. Invasive pneumococcal infections include pneumonia, meningitis, and febrile bacteremia; among the common non-invasive manifestations are otitis media, sinusitis, and bronchitis. At least one million children die of pneumococcal disease every year, most of these being young children in developing countries. In the developed world, elderly persons carry the major disease burden. Conditions associated with increased risk of serious pneumococcal disease include HIV infection, sickle-cell anaemia, and a variety of chronic organ failures. Vaccination is the only available tool to prevent pneumococcal disease. The recent development of widespread microbial resistance to essential antibiotics underlines the urgent need for more efficient pneumococcal vaccines. Immunity following pneumococcal disease is directed primarily against the capsular serotype involved. The currently licensed pneumococcal vaccine is based on the 23 most common serotypes, against which the vaccine has an overall protective efficacy of about 60% to 70%. Children aged < 2 years, and persons suffering from various states of immunodeficiency, for example HIV infection, do not consistently develop immunity following vaccination, thus reducing the protective value of the vaccine in some major target groups for pneumococcal disease. However, in the healthy elderly population, the polysaccharide vaccine provides relatively efficient protection against invasive pneumococcal disease. Extensive clinical trials are now under way with a new generation of pneumococcal vaccines. These protein-polysaccharide combinations, known as conjugate vaccines, contain 7-11 selected polysaccharides bound to a protein carrier, and induce a T-cell dependent immune response. These vaccines are likely to be protective even in children < 2 years of age, and may reduce pneumococcal transmission through a herd effect.

Pneumococcal diseases are a major public health problem all over the world. The etiological agent, Streptococcus pneumoniae (the pneumococcus) is surrounded by a polysaccharide capsule. Differences in the composition of this capsule permit the serological differentiation between about 90 capsular types, some of which are frequently associated with pneumococcal disease, others rarely. Invasive pneumococcal infections include pneumonia, meningitis and febrile bacteremia; among the common noninvasive manifestations are otitis media, sinusitis and bronchitis. At least 1 million children die of pneumococcal disease every year, most of these being young children in developing countries. In the developed world, elderly persons carry the major disease burden. Conditions associated with increased risk of serious pneumococcal disease include HIV infection, sickle-cell anaemia and a variety of chronic organ failures. Vaccination is the only available tool to prevent pneumococcal disease. The recent development of widespread microbial resistance to essential antibiotics underlines the urgent need for more efficient pneumococcal vaccines. Immunity following pneumococcal disease is directed primarily against the capsular serotype involved. The currently licensed pneumococcal vaccine is based on the 23 most common serotypes, against which the vaccine has an overall protective efficacy of about 60%-70%. Children aged < 2 years, and persons suffering from various states of immunodeficiency, for example HIV infection, do not consistently develop immunity following vaccination, thus reducing the protective value of the vaccine in some major target groups for pneumococcal disease. However, in the healthy elderly population the polysaccharide vaccine provides relatively efficient protection against invasive pneumococcal disease. Extensive clinical trials are now under way with a new generation of pneumococcal vaccines. These protein-polysaccharide combinations, known as conjugate vaccines, contain 7-11 selected polysaccharides bound to a protein carrier, and induce a T-cell dependent immune response. These vaccines are likely to be protective even in children aged < 2 years, and may reduce pneumococcal transmission through a herd effect.