Patient Demographics
From March 20 to May 30, 2022, a total of 485 SPP went to the fever clinic, of which 389 finally entered the study, and 22 SPP (5.66%) caused CSS in the separate isolation room. 219 SPP (56.30%) were male. The mean age of SPP was 4.34±3.92 years old and the mean CT value was 12.44±5.11. In total, sampling times with exposure history (SPP in fever clinic on that day or in that separate isolation room)were 9952, including 204 (2.05%) of CSS. (Table 1, Figure 2)
Uni-variate analysis model identifies the factors related to the CSS
The results of the analysis of variables associated with the CSS are presented in Table 4. The analysis confirmed that daily number of SPP was positively associated with CSS (r =0.358; 95% CI [0.050-0.692]), and having confirmed CT value of SPP was negatively associated with CSS (r =-0.38; 95% CI [-0.507-0.523]). However, all results were not statistically significant. (Table 2)
Comparison of different types of the CSS
According to different characteristics of object surfaces, they were divided into three categories, namely, flat surface (FS), hand high-frequency contact parts (HHF) and electronic products (EP). See appendix 1 for specific classification contents.
From March 20 to May 30, 2022, the number (rate) of CSS in the FS, HHF and EP were 40 (2.52%), 22 (1.89%) and 11 (1.73%) respectively in the PA while 87 (4.75%), 65 (3.00%) and 35 (1.82%) in the SIR. Among the three categories, the FS have a highest positive rate, and the EP the lowest. However, there is no significant difference among the three groups. (P>0.05) (Table 3)
Comparison of CSS in the public area and the separate isolation room
In the fever clinic, the patients need to have SARS-CoV-2 nucleic acid test first in the public area (PA), and the waiting time for the results is about 2.5 hours. If positive, they will enter a separate isolation room (SIR) with a parent for separate isolation and treatment, waiting for transfer. From March 20 to May 30, 2022, the number (rate) of CSS in the PA, SIR was 73 (2.15%), 131 (2%) respectively. There was no significant difference between the PA and the SIR. (P>0.05) (Table 3)
Comparison of the CSS with different disinfection methods
Before the statistics, the negative samples with no exposure history (No SARS-CoV-2 positive children in fever clinic on that day or in that SIR) were excluded. When using the chemical disinfection method, the number (rate) of CSS in the PA, SIR was 73 (4.56%), 114 (2.64%) respectively. After using the Ultraviolet radiation + Chemical, the number of CSS were 0(0%), 17 (0.76%), which both decreased significantly. (P<0.05) (Table 3, Figure 3)
Comparison of characteristics of the patients of ordinary SARS-CoV-2 patients and contamination of surfaces related SARS-CoV-2 patients
The patients who caused CSS is defined as contamination of surfaces related SARS-CoV-2 patients (CRP) while not as ordinary SARS-CoV-2 positive patients (OSPP). The male proportion, age, weight, height, CT value, wearing N95 mask rate and in room time were 55.31%, 4.23±3.89 year, 20.08±13.72kg, 101.85±30.64cm, 12.44±5.15, 7.63% and 16.46±4.65h respectively in OSPP while 72.73%, 6.04±4.04 year, 24.38±12.36kg, 115.14±27.67cm, 12.39±4.52, 9.09% and 14.52±9.38h in CRP. Compared with OSPP, CRP is older and the male proportion is higher, but all the differences are not significant. (Table 4)