Viruses as precipitants of asthma symptoms III. Rhinoviruses: molecular biology and prospects for future intervention

In the first twoarticlesin this series [1,2], we examined the epidemiological evidence for an association between respiratory viral infections and asthma exacerbations, and the physiological and experimental evidence for the proposed cellular and biochemical mechanisms involved in this association. As mentioned in Part I, most previous studies have indicated that rhinoviruses are the most common viruses associated with wheezing illness (except in infancy), and are also among the viruses with the greatest propensity to trigger wheezing or asthma attacks. Our own studies among children with recurrent wheeze and/or cough suggested that rhinoviruses may be found in as many as half of all such episodes of respiratory illness—six times as common as the next most common virus [3]. This last article in the series will review recent developments in the molecular biology of rhinoviruses and their receptors, and will examine the potential for preventing or ameliorating attacks precipitated by viral infections.