Clinical and Epidemiologic Characteristics of Spreaders of Middle East Respiratory Syndrome Coronavirus during the 2015 Outbreak in Korea

Kang, Chang Kyung; Song, Kyoung-Ho; Choe, Pyoeng Gyun; Park, Wan Beom; Bang, Ji Hwan; Kim, Eu Suk; Park, Sang Won; Kim, Hong Bin; Kim, Nam Joong; Cho, Sung-il; Lee, Jong-koo; Oh, Myoung-don

Spreaders transmitted MERS-CoV between days 1 and 11 of their illness. Of note, even a 1-or 2-day delay in isolating patients led secondary infections, with a peak of cumulative number on the seventh day of illness. These findings imply that MERS-CoV could be transmitted frequently during the early course of the disease. A recent virus shedding study showed that MERS-CoV titers in sputum samples were around 108 copies per milliliter as early as 3 days after symptom onset, while the viral shedding kinetics of the SARS-CoV infection was an inverted V shape, with its sharp peak around day 10 (13). These findings suggest that control of a MERS-CoV outbreak would be more difficult than that of a SARS-CoV outbreak. Considering that the shortest incubation period of MERS-CoV infection is 2 days and that patients may transmit the disease with a high viral load even in the early course of their illness, early detection and isolation of patients is imperative to control an outbreak of MERS-CoV.