SARS

SARS, or Severe Acute Respiratory Syndrome, is a viral illness caused by the coronavirus SARS-CoV. It emerged in late 2002 in Guangdong Province, China, and triggered a global outbreak that peaked in early 2003. Transmission occurs mainly through respiratory droplets and close person-to-person contact, though airborne transmission could occur in hospital settings. The incubation period is typically 2 to 10 days. Early symptoms include fever, malaise, myalgia, and chills, followed by dry cough, dyspnea, and pneumonia. Some patients present with diarrhea. Laboratory testing, including RT-PCR for viral RNA and serology, supports diagnosis. Chest imaging often shows bilateral infiltrates.

There were more than 8,000 reported cases in 26 countries, with 774 deaths, yielding an overall case fatality rate around 9 to 10 percent, higher in older patients. There is no specific licensed treatment; care is supportive, including oxygen therapy and ventilation as needed. Trials of antivirals such as ribavirin and corticosteroids were used but with limited demonstrated benefit.

Public health response curbed transmission through rapid case finding, isolation, contact tracing, infection control in healthcare facilities, and international cooperation led by the World Health Organization. Travel advisories and airport screening were implemented in many places. By mid-2003 most outbreaks were controlled, and transmission ceased by 2004, with only sporadic exported cases thereafter.

Zoonotic origin evidence links SARS-CoV to animals sold in live markets in southern China, with bats implicated as the natural reservoir and civet cats as an intermediate host.

SARS is distinct from later coronaviruses such as MERS and SARS-CoV-2. See also SARS-CoV-2, coronavirus.