Clinical Course of 11 Cases of SARS-CoV-2 Infection Occurred in A Large Cruise Ship： Factors Associated with Severity and Prolonged Hospitalization

The number of the patients with coronavirus disease 2019 (COVID-19) is increasing, and shortage of hospital beds for these patients is a cause for serious concern Here, we report the clinical course of 11 patients who were admitted to our hospital with COVID-19 that developed during their quarantine period in a large cruise ship, and discuss the factors associated with the disease severity and length of hospitalization The median age of the 11 patients was 62 years, and 36% were men The disease severity was mild in 7 patients, moderate in 4 patients, and severe in none of the patients The median time from symptom onset to disease remission was 13 days for patients with moderately severe disease, and 7 days for patients with mild disease The median interval from symptom onset to confirmation of the first negative result of PCR was 16 days for patients with moderately severe disease, and 14 days for patients with mild disease The median time from symptom onset to discharge was 22 5 days for patients with moderately severe disease cases, and 16 days for patients with mild disease Some patients needed prolonged hospitalization because of persistently positive results of PCR even after remission of symptoms Comparison between the patient groups with moderately severe disease and mild disease showed that the patients with moderately severe disease were older and had higher serum ferritin and serum amyloid protein (SAA) levels than the patients with mild disease Even in patients with mild to moderate COVID-19, two to three weeks were required from symptom onset to confirmation of the first negative result of PCR, and this was one of the major factors for prolonged hospitalization The serum ferritin levels and SAA levels might be predictors of the disease severity