Chapter 29: Rest of the RNA Viruses

The Arboviruses represent a critical group transmitted through arthropod vectors, particularly mosquitoes, encompassing the Togaviridae and Flaviviridae families that produce serious neurological complications including encephalitis syndromes. The Bunyaviridae family includes hantaviruses, which cause severe pulmonary disease through inhalation of contaminated rodent excreta. The Picornaviridae family comprises two major groups: enteroviruses including poliovirus, coxsackievirus, and echovirus, which have shaped vaccine development strategies and public health policy, and rhinoviruses, the predominant causative agents of upper respiratory tract infections. Coronaviruses have emerged as major human pathogens, with recent pandemic strains demonstrating rapid global transmission and variable clinical severity. The chapter addresses viral causes of gastroenteritis, particularly norovirus and other caliciviruses, which produce outbreaks in institutional settings. The Rhabdoviridae family, exemplified by rabies virus, displays distinctive structural features and produces a uniformly fatal infection following symptomatic presentation, with diagnostic pathological findings in neural tissue. The final section covers hemorrhagic fever viruses including filoviruses and arenaviruses, which cause systemic infections with high case fatality rates and substantial tissue damage. Throughout the chapter, emphasis is placed on epidemiological patterns, modes of human-to-human transmission, pathogenic mechanisms that determine disease severity, and strategies for prevention and clinical management of these diverse viral threats.