THE CATARRHAL CHILD 51 are just as exposed to the spread of virus infection. Young children attend nursery schools in greater numbers and from an earlier age and are thus doubly exposed to infection. There are two main types of respiratory viruses. The first type enter the cells of the respiratory tract where they multiply to cause respiratory infections, and among these are the influenzal and para- influenzal viruses, the adenovirus, the respiratory syncytial virus and the rhinovirus. The second type enter the respiratory cells where they cause no local trouble but spread by the blood stream to give rise to the exanthemata such as measles, rubella, varicella, etc. Allergy. Allergy is frequently hereditary in origin, and the child of two atopic parents stands a 75 per cent chance of producing symptoms of nasal allergy. In many cases this is a food allergy, where the allergen is often milk, or an infantile eczema which may lead to nasal catarrh, and often ultimately to hay fever or bronchospasm. Antibiotics. The ready prescription of antibiotics for minor illnesses which normally would recover without such therapy prevents the development of the normal resistance of the child against such infections as the common cold or sore throat. In this respect they create the very conditions that they might be expected to prevent, the susceptibility of the child to upper respiratory tract infections. CLINICAL FEATURES. The complaints include nasal catarrh, frequent upper respiratory tract infections which may proceed to lower respiratory tract infections, sore throats, sore ears, lack of appetite, pallor, insomnia often with spasms of non-productive coughing, and lack of normal growth and development. There are many problems to be resolved in this history. Is the undernourishment and poor appetite due to catarrh, or is the catarrh due to poor appetite? Does the catarrh lead to sinusitis and bronchitis and even bronchiectasis, or is the bronchitis the primary disease and the nasal catarrh secondary to it? Is the insomnia due to nasal catarrh or to poor home condi- tions with overcrowding in which the younger children get no peace to get to sleep ? Is the pallor due to the catarrh or to the lack of fresh air in the house or the lack of playing facilities in high-rise flats ? Is the allergy a true allergy or is it a vasomotor condition engendered by parental anxiety or tensions being communicated to the child? From a more clinical aspect one must consider other factors which may uncommonly predispose to nasal catarrh. Hypothyroidisrn may occasionally play a part. Hypogammaglobulinaemia may rarely predispose to a susceptib- ility to upper respiratory tract infections, giving rise to a condition known as the antibody deficiency syndrome in which the child cannot produce a sufficient natural resistance to infection. Mucoviscidosis may underlie a frequency of upper and lower respiratory tract infections and should always be suspected in intractable cases. The catarrhal child should be thoroughly investigated by the family doctor and the paediatrician to exclude these factors before treatment is undertaken, or before he is examined by the laryngologist. If referral is made in the first instance to an ear, nose and throat clinic the specialist should endeavour to establish in taking the history that there is no general medical problem requiring attention before recommending treatment, and especially before he recommends surgery. The best results are achieved by a collaboration between the two specialists.