Ultrastructural Characterization of SARS Coronavirus

Severe acute respiratory syndrome (SARS) was first described during a 2002–2003 global outbreak of severe pneumonia associated with human deaths and person-to-person disease transmission. The etiologic agent was initially identified as a coronavirus by thin-section electron microscopic examination of a virus isolate. Virions were spherical, 78 nm in mean diameter, and composed of a helical nucleocapsid within an envelope with surface projections. Herein, we show that infection with the SARS-associated coronavirus resulted in distinct ultrastructural features: double-membrane vesicles, nucleocapsid inclusions, and large granular areas of cytoplasm. These three structures and the coronavirus particles were shown to be positive for viral proteins and RNA by using ultrastructural immunogold and in situ hybridization assays. In addition, ultrastructural examination of a bronchiolar lavage specimen from a SARS patient showed numerous coronavirus-infected cells with features similar to those in infected culture cells. Electron microscopic studies were critical in identifying the etiologic agent of the SARS outbreak and in guiding subsequent laboratory and epidemiologic investigations

Dear President Clinton : voices from Asia and the Pacific

For more about the East-West Center, see http://www.eastwestcenter.org/On the eve of President Clinton's trip to Tokyo to attend the July summit of industrial nations, the East-West Center asked 14 leading Asian and Pacific journalists-all of whom have been associated with the Center-for their assessments and expectations of America's new leadership. Addressed directly to the president, the resulting "letters" reveal the complex issues America faces in the region. There is often agreement on issues: "The tough U.S. position on trade comes at a time when your government has not shown any real commitment to regional security in Asia," says a Thai journalist, summing up the feelings of many. But sharp disagreements also emerge: Some writers applaud the president's emphasis on human rights, while others feel America's view cannot easily be accepted in Asia. One message comes through clearly: While America has a large reservoir of goodwill throughout the region, dissatisfactions are mounting. As the writer from Australia states: "The warning signs are there for Americans to see, if only they will pay attention.