2003 emergence of the severe acute respiratory disease coronavirus (SARS-CoV) demonstrated that CoVs are also capable of causing outbreaks of severe infections in humans. A second severe CoV, Middle East respiratory syndrome coronavirus (MERS-CoV), emerged in 2012 in Saudi Arabia. More recently, a novel coronavirus was identified in Wuhan, China, in December 2019
The only recognized SARS-CoV outbreak began in China in 2002 and spread internationally, most notably to Toronto, Canada. From November 2002 to July 2003, the World Health Organization (WHO) reported 8,437 SARS cases and 813 deaths.6 Like other coronaviruses, SARS-CoV is transmitted from person to person through respiratory droplets and close contact.
The incubation period is 4 days (range 1 to 13 days). The main symptoms of SARS are fever, headache, and discomfort. The case fatality risk is approximately 10%.
MERS-CoV was first identified in Saudi Arabia in 2012. To date, there have been more than 2,400 cases, mostly in the Middle East.7 Individual cases and small clusters continue to be reported in that region. Travel-related MERS cases have also been reported in South Korea, where it caused a significant hospital-based outbreak in 2015, and in the United States, where 2 very mild cases were diagnosed. MERS-CoV is transmitted from person to person via respiratory droplets and close contact.
The incubation period is 5 days (range 2 to 15 days). The main symptoms of MERS are fever, chills, generalized myalgia, cough, shortness of breath, nausea, vomiting, and diarrhea. The case fatality risk is approximately 35%.
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Zaki AM, van Boheemen S, Bestebroer TM, Osterhaus AD, Fouchier RA. Isolation of a novel coronavirus from a man with pneumonia in Saudi Arabia. N Engl J Med 2012;367(19):1814-1820.