ABSTRACT

This chapter aims to summarize knowledge on mixed viral infections regarding epidemiological studies and to describe the potential impact of coinfection on disease outcomes. Mixed respiratory viral infections in adults have scarcely been studied, and therefore their clinical relevance remains unknown. The occurrence of viral codetections has received scarce attention, probably because the previously available detection methods lacked sensitivity. In children, according to several epidemiological studies, it may be assumed that the simultaneous presence of more than one viral pathogen would be associated with epidemiological and clinical features that differ from single infections, especially with respect to disease type and severity. The incidence of dual respiratory viral infections varies from 10% to 30% in hospitalized infants with bronchiolitis and may have an impact on the severity of the disease. The diagnosis of viral infections pursues several objectives. Most often, in a clinical setting, it is to prove the viral etiology of a suspected disease.