Highly contagious respiratory illness characterized by a persistent fever, headache, and bodily discomfort, followed by a dry cough that may progress to great difficulty in breathing. SARS appeared in November 2002 in Guangdong province, China, and was brought to Hong Kong in February 2003. As it spread from there to other countries of East Asia and the world, health authorities instituted an unprecedented series of control measures, including quarantines and prohibitions on travel, and in June 2003 the global outbreak was declared to be contained. By that time more than 8,000 cases had been reported, and some 800 people had died. SARS is believed to be caused by a mutant coronavirus, a type usually associated with pneumonia and the common cold. A specific vaccine has not been developed. Treatment is usually restricted to easing the patient's symptoms—providing mechanical ventilation if necessary—until the illness has run its course.
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Viral infection of the upper and sometimes the lower respiratory tract. Symptoms, which are relatively mild, include sneezing, fatigue, sore throat, and stuffy or runny nose (but not fever); they usually last only a few days. About 200 different strains of virus can produce colds; they are spread by direct or indirect contact. The cold is the most common of all illnesses; the average person gets several every year. Incidence peaks in the fall. Treatment involves rest, adequate fluid intake, and over-the-counter remedies for the symptoms. Antibiotics do not combat the virus but may be given if secondary infections develop.
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