Introduction

This chapter describes infections which affect the upper respiratory tract from its origin in the nasal passages as far as the trachea. It covers the common cold, nasopharyngotonsillitis syndrome, epiglottitis, laryngitis, tracheitis, sinusitis, and otitis media. Particular emphasis is given to adults. Chapter 23 details respiratory tract infections in the paediatric group.

The common cold

The common cold (actually a collection of symptoms) is probably the most frequently encountered acute disabling illness (Table 25.1). Although self-limiting, tens of millions of school or working days in developed countries are sacrificed annually, self-medication with costly over-the-counter drugs is widespread despite lack of marked efficacy in many, physician visit time is enormous and abuse of antibiotic prescriptions common. It is estimated that most individuals have between two and ten colds per year, the frequency being twofold higher in children compared to adults, in women and in crowded environments.

Aetiology/pathology

The common cold is caused by a number of agents. The aetiological agents are, in 40% of cases rhinoviruses (>100 serotypes), coronaviruses (>three types) 15%, adenovirus (>30 serotypes), parainfluenza (four types), RSV (two types), influenza A, B and C and enterovirus/rubeola/rubella/varicella in up to 5% each. Presumptive but unknown viruses may be responsible for approximately one-quarter of cases of the common cold, whilst some bacteria, notably group A β-haemolytic Streptococcus may present with common cold symptomatology.