Serologic responses of 42 MERS-coronavirus-infected patients according to the disease severity

Ko, Jae-Hoon; Müller, Marcel A.; Seok, Hyeri; Park, Ga Eun; Lee, Ji Yeon; Cho, Sun Young; Ha, Young Eun; Baek, Jin Yang; Kim, So Hyun; Kang, Ji-Man; Kim, Yae-Jean; Jo, Ik Joon; Chung, Chi Ryang; Hahn, Myong-Joon; Drosten, Christian; Kang, Cheol-In; Chung, Doo Ryeon; Song, Jae-Hoon; Kang, Eun-Suk; Peck, Kyong Ran

We evaluated serologic response of 42 Middle East respiratory syndrome coronavirus (MERS-CoV)-infected patients according to 4 severity groups: asymptomatic infection (Group 0), symptomatic infection without pneumonia (Group 1), pneumonia without respiratory failure (Group 2), and pneumonia progressing to respiratory failure (Group 3). None of the Group 0 patients showed seroconversion, while the seroconversion rate gradually increased with increasing disease severity (0.0%, 60.0%, 93.8%, and 100% in Group 0, 1, 2, 3, respectively; P = 0.001). Group 3 patients showed delayed increment of antibody titers during the fourth week, while Group 2 patients showed robust increment of antibody titer during the third week. Among patients having pneumonia, 75% of deceased patients did not show seroconversion by the third week, while 100% of the survived patients were seroconverted (P = 0.003).