Acute Respiratory Virus Infections

Abstract

Most of the acute respiratory disease seen in general practice every winter is caused by viruses. The main aim of research over the last 20 years has been to find out if one particular type of virus could be incriminated as the commonest cause of all the varied clinical manifestations of acute respiratory disease (A.R.D.) and the main cause of death, so that efficient methods of control could be developed. It is now obvious that this simple hope will never be realized and that no vaccine will ever abolish A.R.D. at a stroke. Over 150 different viruses have been isolated from outbreaks of acute respiratory disease, and antibody acquired against one virus rarely gives any cross-protection against any of the others. Furthermore, almost all the clinical pictures of A.R.D. can be caused by most viruses. This is not surprising since the respiratory tract can respond in only a limited number of ways to any noxious stimulus: over-stimulation of mucous secretion and the cough reflex may be followed by loss of ciliary activity, shedding of mucosa, spasm or paralysis of bronchial smooth muscle and ultimately by retention of secretions, alveolar collapse or consolidation. Nevertheless, only a few of the possible interactions of virus and host involve a risk to life and merit exceptional effort. For example, acute bronchial infections of infants caused by respiratory syncytial (R.S.) virus are far more sinister than infection of this age group by any other respiratory virus; yet in older children and adults R.S. infections are more common but so trivial as to deserve no special attention. © 1973, British Medical Journal Publishing Group. All rights reserved.