Survival of Severe Acute Respiratory Syndrome Coronavirus (2005)

This research paper was published in 2005 and relates to SARS-CoV (responsible for the 2002/03 SARS outbreak), not SARS-CoV-2 (responsible for COVID-19). However, since these two viruses are closely related, it is insightful to observe what is known about the former, in order to consider what may be possible (or even likely) for the latter.

The journal “Clinical Infectious Diseases” appears to be a well-respected journal (ranked by InCites Journal Citation Reports in Quartile 1 for each of “Immunology”, “Infectious Diseases”, and “Microbiology”) [I checked this since the misspelling of the important word “fomites” in the very first sentence raised a red flag about authenticity/quality].

The paper reinforces up-front that the primary modes of transmission of SARS-CoV appear to be direct mucus membrane contact with infectious droplets and through exposure to contaminated surfaces (fomites). Due particularly to the latter, knowledge of the survival characteristics of the virus is essential for identifying appropriate infection-control measures.

This study reports the results of experiments designed to investigate the survival of SARS-CoV strain GVU6109 in faecal and respiratory specimens. The focus is on potential transmission in a clinical setting, which is clear by the nature of the surfaces in which the viral survival tests were conducted, including a laboratory request form, an impervious disposable gown, and a cotton nondisposable gown. The disinfection performances of sodium hypochlorite, household detergent, and a commercial peroxygen compound were also investigated.

The experiments described in this paper did not test faecal samples from SARS-infected patients. Instead, four uninfected faecal samples were used and a 10% suspension of each was prepared in phosphate-buffered saline solution. After centrifugation, the supernatant was collected and a total of 1.8 mL of each 10% stool suspension was spiked with 0.2 mL of virus stock. These samples were incubated in closed containers at room temperature (20°C) for periods of between 30 min and 7 days.

The SARS-CoV strain (GVU6109) used in this study had been isolated from a lung tissue specimen obtained from a patient during the SARS outbreak in 2003. To test “survival” in these experiments, the virus was inoculated into the Vero E6 cell line, which was grown in minimum essential medium (MEM) with 2% fetal calf serum at 37°C.

Surviving SARS-CoV was not recoverable within 1 day after incubation in normal adult faecal specimens or within 3 hours after incubation in a baby faecal specimen. However, it survived for 4 days in a diarrheal faecal specimen. The duration of survival for SARS-CoV in this faecal suspension was retested in another 2 diarrheal specimens, with the same results.

SARS-CoV was also reported to survive in respiratory specimens, such as a nasopharyngeal aspirate specimen, as well as throat and nasal swab specimens, for >7 days at room temperature and for >20 days at 4°C.

Even at a relatively high concentration, the virus could not be recovered after drying of a paper request form, and its infectivity was shown to last longer on the disposable gown than on the cotton gown. All disinfectants tested were shown to achieve >3 Log10 inactivation within 5 min.

The authors concluded that faecal and respiratory samples can remain infectious for numerous days at room temperature. They also surmised that the risk of infection via contact with droplet-contaminated paper is small; and that and that absorbent material, such as cotton, is preferred to nonabsorptive material for PPE in some circumstances.

REFERENCE:

Lai MYY, Cheng PKC and Lim WWL (2005) Survival of Severe Acute Respiratory Syndrome Coronavirus. Clinical Infectious Diseases, 41(7), e67-e71.

https://doi.org/10.1086/433186

Published by Stuart Khan

Professor of Civil & Environmental Engineering, University of New South Wales

2 thoughts on “Survival of Severe Acute Respiratory Syndrome Coronavirus (2005)

  1. Does SARS -Cov-2 survival is similar to SARS -Cov?

    There were some reports to say even after the passengers left the cruise ship (Japan) they found the virus on the surface after 14 days?

    What’s the chances of COVID -19 finding its way in water supply systems? Faecal route?

    Looks like it could survive for number of days> 20 days in cold waters.

    Disinfectants are effective for waters of low turbidities and DOC in the final waters.

    Once in the water network they could survive within the biofilms.

    All indications are that the risk is low to drinking water!

    Any thoughts ?

    Liked by 1 person

    1. Thanks for asking these questions Dharma.

      They’re exactly the questions that we are working to accumulate the evidence to answer on this blog! I think you’ll find some good information here already, for example:

      Yes, based on studies with surrogate viruses, we expect long survival in very clean (sterile) cold (4 deg C) water. But survival appears to be shorter in natural surface waters, especially at warmer (25 deg C) temperatures. You can find this paper (“Survival of surrogate coronaviruses in water”) by selecting “lake water” or “temperature” from the word cloud on the blog front page.

      And yes, we expect chlorine disinfection to be very effective and risks in drinking water to be low. These questions are discussed in two papers by Dr Krista Wigginton. You can also find them both by selecting “Disinfection” or “Drinking Water” from the word cloud on the blog front page.

      I don’t think we currently have evidence to support an answer to your question regarding biofilms. But if you find something please send it over and we’ll be keen to include it.

      SK.

      Like

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