The characteristics of hDPP4 transgenic mice subjected to aerosol MERS coronavirus infection via an animal nose-only exposure device

Hao, Xin-yan; Lv, Qi; Li, Feng-di; Xu, Yan-feng; Gao, Hong

High levels on days 3 to 5 Middle East respiratory syndrome patients exhibit a median incubation period of 5-7 days, with a range of 2-14 days. 41 We discovered that instillation-inoculated mice exhibited clinical signs within 1 day but that the incubation period of aerosol-exposed mice was 5-7 days, which more closely resembled the period observed in humans. MERS-CoV binds to hDPP4 receptors that are primarily expressed in the lower respiratory tract and alveoli, resulting in a wide range of disease symptoms in patients, from no symptoms to mild respiratory illness or severe acute pneumonia, which rapidly progresses to acute lung damage, multiorgan failure and even death. 42, 43 Clinically, chest radiography and chest computed tomography (CT) show no lung lesions in patients in the early stages of illness, but pneumonia is identified during the course of the disease and includes patchy densities, extensive diffuse and focal alveolar space opacities, interstitial infiltrates, and consolidation. 44 pulmonary pathological changes in aerosol-infected mice were similar to those noted in patients with respiratory tract infection.