Human Metapneumovirus: Discovery, Characterisation and Associated Disease

Abstract

Acute respiratory tract infections are responsible for considerable morbidity and mortality and costs attributable to acute respiratory tract illnesses (ARI) are an important burden on national health care budgets. A variety of viruses, bacteria and fungi are associated with ARI. This thesis only focuses on viral causes of ARI Diagnosis of respiratory tract infections is important for adequate treatment of patients and community surveillance studying the spread of respiratory viruses forms the basis for preventive strategies. Despite the use of a variety of diagnostic assays, 15-50% of the samples obtained from persons suffering from ARI do not yield positive diagnoses, which is at least in part due to limitations of diagnostic procedures. However, a proportion of ARI may be caused by still unknown pathogens, providing an additional explanation for the relatively high proportion of negative laboratory diagnoses. This thesis describes the identification and characterisation of a hitherto unknown virus as the causative agent of ARI, which was subsequently found to be responsible for a high portion of the unexplained ARI. In this introduction background information on characteristics, diagnostics and epidemiology of known respiratory viruses will be provided.