On January 27, a 46-year-old woman had been dining (at the same table) for several consecutive days with a patient who was definitively diagnosed with the new coronavirus infection. During the period of isolation, the nucleic acid test of her throat swab was found to be positive, and she was admitted to the hospital on February 8, 2020 (Fig.
1b). She had a fever on the first day of admission but no cough, chest tightness or other symptoms. She did not have cardiovascular disease, diabetes or other underlying diseases. Chest CT examination showed scattered thin patchy shadows and inflammatory manifestations in both lungs. Laboratory tests excluded
Mycoplasma pneumoniae and other causes of viral pneumonia, such as influenza A virus H1N1, H1N1 (2009), H3N2, H5N1, H7N9, influenza B virus (BV and BY types), human coronavirus (229E/HKU1/OC43/NL63/SARS/MERS), parainfluenza virus (1–3), and rhinovirus A/B/C. Routine blood tests showed a WBC count of 6.70 × 10
9/L, lymphocyte ratio of 24.9%, and CRP level of 0.5 mg/L. Blood gas tests showed a PaO
2 of 99 mmHg and PaO
2/FiO
2 of 0.99. Blood chemistry results were as follows: ALT level of 24 U/L, AST28, urea level of 3.0 mmol/L, creatinine level of 46 μmol/L, D2 level of 0.27 μg/L, and CK-MB level of 12 U/L (Figure S
3E-H). The diagnosis was COVID-19 (moderate type). After admission, the patient was treated with interferon atomization inhalation (5 million units each time, twice a day) and lopinavir tablets [2 capsules each time (50 mg each capsule), twice a day], in addition to traditional Chinese medicine (Qingfei Paidu Decoction) as an auxiliary treatment. The patient tested negative for nucleic acid by swabs of the nose, pharynx and anus three times on February 17th, 18th, and 19th; imaging of the two lungs revealed a scattered thin film, which was more absorbed than before. The patient was discharged from the hospital on the 23rd and then sent to the local area for continued isolation. One week later, nucleic acid re-examination using nose and (rectal) swabs showed positive results, though the throat swab was negative; the patient was immediately admitted to the hospital. Imaging examination showed the scattered thin film in the two lungs, with little change compared with the previous imaging results (Figure S
4). Serum antibody detection indicated weak positivity for IgM antibodies and positivity for IgG antibodies. Routine blood tests showed a WBC count of 3.30 × 10
9/L, lymphocyte ratio of 32.8%, and CRP level of 8.04 mg/L. The patient did not receive another treatment after readmission except for continuous atomizing with recombinant interferon. Nucleic acid testing of three consecutive swabs of the nose, pharynx and anus were all negative on March 11th, 12th, and 13th. Imaging revealed basic absorption of both lung lesions. The serum antibody test was negative for IgM antibodies and positive for IgG antibodies, and routine blood and blood chemistry tests were normal. The patient was discharged from the hospital and sent to the local Community Health Service Center for continued isolation. After 2 weeks and 4 weeks, all re-examination tests were normal, and the patient was released from isolation after recovery.