The Korean Middle East Respiratory Syndrome Coronavirus Outbreak and Our Responsibility to the Global Scientific Community

Oh, Myoung-don

It is plausible that a higher infective dose of MERS-CoV can lead to a shorter incubation period and more severe pneumonia. A recent study showed that a shorter incubation period was associated with a higher risk of death [6] . The authors reported viral shedding kinetics of MERS-CoV in a separate journal [7] , showing that the peak titers of MERS-CoV in respi-Oh MD • MERS and our responsibility www.icjournal.org 146 ratory samples were similar among the moderate, severe and fatal groups. These results suggest that severe pneumonia is possibly a result of host immune response to MERS-CoV, rather than the virus infection per se, as in severe acute respiratory syndrome [8] . Indeed, a recent autopsy study showed that the pathologic basis for MERS-CoV pneumonia was pulmonary edema, type 2 pneumocytes hyperplasia, diffuse alveolar damage with hyaline membrane formation, and interstitial pneumonia with lymphocytic infiltration and syncytium formation [9] . Therefore, a patient with severe pneumonia does not necessarily shed a higher titer of MERS-CoV in the respiratory secretion, and is not necessarily more infectious .