First data on stability and resistance of SARS coronavirus compiled by members of WHO laboratory network

The below table provides the first compilation of data on resistance of the SARS Coronavirus against environmental factors and disinfectants. This information has been provided by Members of the WHO multi-center collaborative network on SARS diagnosis. More detailed information on methods utilized and material used is being compiled and will be available shortly. The major conclusions from these studies are:

Virus survival in stool and urine

Virus is stable in faeces(and urine) at room temperature for at least 1-2 days.

Virus is more stable (up to 4 days) in stool from diarrhea patients (which has higher pH than normal stool).

Disinfectants

Virus loses infectivity after exposure to different commonly used disinfectants and fixatives.

Virus survival in cell-culture supernatant

Only minimal reduction in virus concentration after 21 days at 4°C and -80°C.

Reduction in virus concentration by one log only at stable room temperature for 2 days. This would indicate that the virus is more stable than the known human coronaviruses under these conditions.

Heat at 56°C kills the SARS coronavirus at around 10000 units per 15 min (quick reduction).

Fixatives (for use in laboratories only)



SARS virus fixation (killing) on glass slides for immunofluorescence assays in room temperature does not kill virus efficiently unless the acetone is cooled down to -20oC.

Lab* Substrate Initial viral count log 10PFU Condition Survival time Method of testing viability GVU virus spiked in baby stool 1.00E+03 pH 6-7 3 hr Virus isolation in cell culture virus spiked in normal stool 7.50E+03 pH 8 6hr Virus isolation in cell culture virus in diarrheal stool 7.50E+03 pH 9 4days Virus isolation in cell culture QMH stool 1.00E+03 Room Temperature at least 2 days Virus isolation in cell culture urine 1.00E+03 Room Temperature at least 24 hr Virus isolation in cell culture Virus culture medium+ 1% bovine serum 1.00E+03 on plastic surface in room temperature at least 2 days Virus isolation in cell culture Virus culture medium+ 1% bovine serum 1.00E+04 30-37°C at least 1hr Virus isolation in cell culture Virus culture medium+ 1% fetal calf serum 1.00E+04 56°C degration of titre over time (10 000 infectious virus units in 15 min) Virus isolation in cell culture virus in Acetone, 10% Formaldehyde and Paraformaldehyde, 10% Clorox, 75%ethanol, 2% phenol 1.00E+06 Room Temperature less than 5 min Virus isolation in cell culture NIID Virus culture+ 2% bovine serum 1.00E+06 minus 80°C at least 4 days Virus isolation and RT-PCR Virus culture+ 2% fetal calf serum 1.00E+06 4°C at least 4 days Virus isolation and RT-PCR Virus culture+ 2% fetal calf serum 1.00E+06 37°C less than 4 days Virus isolation and RT-PCR Virus culture+ 2% fetal calf serum 1.00E+05 56°C less than 30min UniM Virus culture 1.00E+06 4°C at least 21 days Virus isolation Virus culture 1.00E+06 minus 80°C at least 21 days Virus isolation CUHK Virus in phosphate buffered saline (PBS)

Virus in sterilized stool 9.00E+04 Room Temperature on PBS Stool Virus isolation in cell culture plastered wall 24h 36h plastic surface 36h 72h formica surface 36h 36h stainless steel 36h 72h wood 12h 24h cotton cloth 12h 24h pig skin ≥24h ≥24h glass slide 72h 96h paper file cover 24h 36h

CUHK Chinese University Hong Kong

GVU: Government Virus Unit, Dept. of Health, Hong Kong, SAR China

QMH: Queen Mary Hospital, The University of Hong Kong, Hong Kong, SAR China

NIID: National Institute of infectious Diseases, Tokyo, Japan

UnivM: University Marburg, Germany

