Results

Air samples
Of the 44 air samples collected in medical areas, none of all was positive for SARS-CoV-2 as assessed by RT- PCR (Table 1 ).
Table 1 Positive rate of air samples from different departments in medical areas
Areas NO.of tests NO.of Positive Positive rate (%)
General isolation wards 13 0 0.00
Ward 1 3 0 0.00
Ward 2 3 0 0.00
Ward 3 1 0 0.00
Ward 4 2 0 0.00
Ward 5 3 0 0.00
Ward 6 1 0 0.00
Intensive care units 13 0 0.00
Fever clinic 18 0 0.00
Emergency room 3 0 0.00
Observation room 1 0 0.00
Treatment room 1 0 0.00
Infusion room 1 0 0.00
Diagnosis room 1 2 0 0.00
Diagnosis room 2 2 0 0.00
Throat swab sampling room 2 0 0.00
Public area 6 0 0.00
Total 44 0 0.00

Environmental surface samples
The positive rates of samples from environmental surfaces in different areas are shown in Table 2 . Of the 200 swab samples taken from environmental surfaces, 38 were positive for SARS-CoV-2 RNA. Thirty-six (24.83%) of the 145 samples collected in medical areas and 2 (3.64%) of the 55 collected in living quarters were positive for the virus. The positive rate in medical areas was significantly higher than that in living quarters (P = .001). The positive rates were 25.00% and 37.50% for the general isolation ward and ICU, respectively, and no significant difference was observed between these regions (P = .238). Two positive samples were detected in the office area, one was detected on the surface of a keyboard, and another was on the surface of a telephone.
Table 2 Positive rate of samples from environmental surface in different areas
Areas No. of tests No. of positive Positive rate (%)
Medical areas 145 36 24.83
General isolation ward 72 18 25.00
Ward 1 12 6 50.00
Ward 2 12 0 0.00
Ward 3 12 4 33.33
Ward 4 12 3 25.00
Ward 5 12 1 8.33
Ward 6 12 4 33.33
Intensive care units 24 9 37.50
Clinical laboratory 7 0 0.00
Fever clinic 42 9 21.43
Emergency room 12 6 50.00
Observation room 4 1 25.00
Treatment room 4 0 0.00
Infusion room 4 0 0.00
Diagnosis room 1 4 1 25.00
Diagnosis room 2 4 0 0.00
Throat swab sampling room 8 0 0.00
Public area 2 1 50.00
Living quarters 55 2 3.64
Office area 22 2 9.09
Rest room 33 0 0.00
Total 200 38 19.00
The positive rates of samples from environmental surfaces of specific sites in medical areas are presented in Table 3 . In medical areas, the PCR-positive samples were obtained from the surface of keyboards, computer mice, beepers, bedside tables, bedrails, and medical equipment including ventilators and monitors. In living quarters, the PCR-positive samples were obtained from the surface of telephones and desktop. Samples taken from the surface of beepers (50.00%), water machine buttons (50.00%), elevator buttons (42.86%), computer mouses (40.00%), telephones (40.00%), and keyboards (33.33%) were positive for SARS-CoV-2 RNA.
Table 3 Positive rate of samples from environmental surface of specific sites in medical areas
Sampling site No. of tests No. of positivity Positive rate (%)
Beepers 6 3 50.00
Water machine buttons 8 4 50.00
Elevator buttons 7 3 42.86
Computer mouses 10 4 40.00
Telephones 10 4 40.00
Keyboards 15 5 33.33
Medical equipment 13 4 30.77
Oxygen cylinder valve 8 2 25.00
Desktops 18 3 16.67
Bedrails 7 1 14.29
Bedside tables 7 1 14.29
Gloves 7 1 14.29
Door handles 15 0 0.00
Others 14 1 7.14
Total 145 36 24.83