SARS coronavirus infection: pathology and pathogenesis of an emerging virus disease

Abstract

Severe acute respiratory syndrome (SARS) was first recognized during a global outbreak of severe pneumonia that first occurred in late 2002 in Guangdong Province, China, and then erupted in February 2003 with cases in more than two dozen countries in Asia, Europe, North America, and South America. The disease causes an influenza-like illness with fever, cough, dyspnea, and headache, and in severe cases, it can cause human death. Person-to-person transmission, combined with international travel of infected persons, accelerated the worldwide spread of the illness, and by the time the outbreak was contained, 8,098 probable cases resulting in 774 deaths were reported [1–4]. During the outbreak, a global network of 11 laboratories was established by the World Health Organization (WHO) to identify the causal agent. Early in the investigation, the clinical, pathologic, and laboratory studies focused on previously known agents of respiratory illness. Subsequently, however, a previously unknown virus was isolated from the oropharynx of a SARS patient and identified by ultrastructural characteristics as belonging to the family Coronaviridae [5–7]. These findings shifted the focus of the investigation toward verification of the role played by this newly recognized coronavirus. A vast array of laboratory approaches was utilized in this investigation, including pathologic, serologic, and molecular assays [6–10]. Within weeks, infection of non-human primates was achieved, thus establishing an animal model for SARS coronavirus (SARS-CoV) [11]. This chapter presents the morphologic characteristics of SARS-CoV grown in tissue culture and the histopathologic changes, electron microscopic findings, and cellular localization of the virus in tissues from human patients and experimentally infected animals. In addition, the pathophysiology of this newly emergent virus will be discussed. SARS coronavirus infection: pathology and pathogenesis of an emerging virus disease