COVID-19: A Comparative Study of Population Aggregation Patterns in the Central Urban Area of Tianjin, China.

When a public health emergency occurs, a potential sanitation threat will directly change local residents' behavior patterns, especially in high-density urban areas. Their behavior pattern is typically transformed from demand-oriented to security-oriented. This is directly manifested as a differentiation in the population distribution. This study based on a typical area of high-density urban area in central Tianjin, China. We used Baidu heat map (BHM) data to calculate full-day and daytime/nighttime state population aggregation and employed a geographically weighted regression (GWR) model and Moran's I to analyze pre-epidemic/epidemic population aggregation patterns and pre-epidemic/epidemic population flow features. We found that during the COVID-19 epidemic, the population distribution of the study area tended to be homogenous clearly and the density decreased obviously. Compared with the pre-epidemic period: residents' demand for indoor activities increased (average correlation coefficient of the floor area ratio increased by 40.060%); traffic demand decreased (average correlation coefficient of the distance to a main road decreased by 272%); the intensity of the day-and-night population flow declined significantly (its extreme difference decreased by 53.608%); and the large-living-circle pattern of population distribution transformed to multiple small-living circles. This study identified different space utilization mechanisms during the pre-epidemic and epidemic periods. It conducted the minimum living security state of an epidemic-affected city to maintain the operation of a healthy city in the future.

Changes in Characteristics, Treatment and Outcome in Patients with Hemorrhagic Stroke During COVID-19.

BACKGROUND AND PURPOSE: The coronavirus disease 2019 (COVID-19) pandemic has had a comprehensive impact on healthcare services worldwide. We sought to determine whether COVID-19 affected the treatment and prognosis of hemorrhagic stroke in a regional medical center in mainland China. METHODS: Patients with hemorrhagic stroke admitted in the Neurosurgery Department of West China Hospital from January 24, 2020, to March 25, 2020 (COVID-19 period), and from January 24, 2019, to March 25, 2019 (pre-COVID-19 period), were identified. Clinical characteristics, hospital arrival to neurosurgery department arrival time (door-to-department time), reporting rate of pneumonia and 3-month mRS (outcome) were compared. RESULTS: A total of 224 patients in the pre-COVID-19 period were compared with 126 patients in the COVID-19 period. Milder stroke severity was observed in the COVID-19 period (NIHSS 6 [2-20] vs. 3 [2-15], p = 0.005). The median door-to-department time in the COVID-19 period was approximately 50 minutes longer than that in the pre-COVID-19 period (96.5 [70.3-193.3] vs. 144.5 [93.8-504.5], p = 0.000). A higher rate of pneumonia complications was reported in the COVID-19 period (40.6% vs. 60.7%, p = 0.000). In patients with moderate hemorrhagic stroke, the percentage of good outcomes (mRS < 3) in the pre-COVID-19 period was much higher than that in the COVID-19 period (53.1% vs. 26.3%, p = 0.047). CONCLUSIONS: COVID-19 may have several impacts on the treatment of hemorrhagic stroke and may influence the clinical outcomes of specific patients. Improvements in the treatment process for patients with moderate stroke may help to improve the overall outcome of hemorrhagic stroke during COVID-19.