Background: As a new infectious disease, coronavirus disease 2019 (COVID-19) is not fully understood. During January - July 2020, there were two clusters infections in Beijing, China. This study was to analyze the features of the two COVID-19 infections in Beijing.
Methods: In this retrospective single-center study, 89 cases with the positive novel coronavirus nucleic acid test were collected from January to July 2020 in Beijing. They were divided into January-March group and June-July group. Two groups of data were compared.
Results: The eighty-nine cases, 47 males and 42 females, mean age (41±14 years), were used for our study. The most common symptoms were fever (46/89, 52%) and cough (34/89, 38%). The clinical classification were moderate type (56/89,63%), mild type (24/89, 27%), severe type (4/89, 4%), critical type (0), respectively. Ground glass opacity (GGO) (47%) was the majority CT pattern. The frequency of involvement of lower lobe was higher than that of upper lobe (P＜0.01). In January - March group, there were 5 patients (18%) exposure to Wuhan, 15 patients (54%) family clusters, 5 patients (18%) colleague clusters, 3 patients (11%) imported cases. In June-July group, 41 patients (68%) had an exposure to Xinfadi market of Beijing, 6 patients (10%) family clusters, and 14 patients (23%) colleague clusters. The number of patients with fever, cough, chest CT severity score and the number of lesion lung lobes in January-March group was higher than that in June-July group (P＜0.05).
Conclusions: Two COVID-19 clusters were dominated moderate and mild type, but few severe types. Patients in June-July group had less symptoms, imaging and family clusters than that in January-March group. This suggested that closely monitoring, early quarantined, nucleic acid test of COVID-19 and chest CT were important measures to prevent epidemic.