Middle East respiratory syndrome (MERS-CoV).

Epidemiology on the ground identifies and tracks a new respiratory virus. L ast year, the infectious disease and public health communities learned of a new severe acute respiratory infection in Saudi Arabia. The stunningly rapid identification of the causative organism, the development of a diagnostic assay, online and ahead-of-print publishing, and heightened global surveillance efforts have made it possible to track the slow emergence of this new, often deadly infection. In September 2012, a post on ProMED-mail reported that a novel human coronavirus had been isolated from the sputum of a 60-year-old Saudi Ara-bian man with pneumonia. 1 (ProMED-mail, found at www.promedmail.org, is a free, Internet-based global reporting system from the International Society for Infectious Diseases that rapidly disseminates information on outbreaks of infectious disease and toxin exposures.) The man died from acute respiratory distress syndrome and renal failure in June 2012. 2 A pan-coronavirus assay of postmortem lung tissue was positive. (Coronaviruses, named for the crown-like projections on their surfaces, are among the viruses that cause the common cold.) The virus was forwarded to a research lab in Rotterdam, the Nether-lands, where it was further identified as a new human coronavirus closely related to two bat coronaviruses. 2 This disease would later be named Middle East respiratory syndrome (MERS), and the organism would be named MERS-CoV. Also in September 2012, a previously healthy 49-year-old man from Qatar (just east of Saudi Ara-bia) was hospitalized with severe respiratory symptoms and soon airlifted to a London ICU. With no diagnosis yet established, and because there were similarities between the Qatar case and the one described in ProMED-mail, the Qatari patient was tested for coronavirus. The pan-coronavirus assay was positive. The United Kingdom's Health Protection Agency then contacted the virologists in Rotterdam, who subsequently confirmed a 99.5% match between the viruses of the two patients. 3 Remarkably, within a month, two real-time reverse-transcription–polymerase chain reaction assays for the novel coronavirus were devised. 4 A test was essential not only for the confirmation of suspected cases, but to permit researchers to analyze the natural course of the infection—the body fluids into which the virus sheds, the duration and peak of viral shedding (indicating likely transmission periods), and the body's response to treatment. In addition, asymptomatic contacts could now be tested, possibly yielding epide-miologic clues about how these infections spread. When an emerging infection is first recognized, clinicians and epidemiologists focus on several key …