Page 74 - JSOM Summer 2023

The Effect of Laundering with Tap Water, High Heat, particles. They are composed of a lipid envelope that sur-
and No Detergent on the Stability of SARS-CoV2 on the rounds a protein capsid. The highly unstable RNA genome is
Army Combat Uniform maintained within the capsid. Washing with detergent lyses the
Since military personnel in the deployed environment may lipid envelope and releases the viral capsid. Detergents, how-
have hot water by boiling or exposure to heat in the environ- ever, typically have no effect on the capsid itself. It is, therefore,
ment but may not have access to detergent, an experiment was reasonable to assume that components of the lipid envelope
conducted to determine if a wash step using high-temperature are responsible for holding the viral particle to the ACU mate-
water without added detergent would remove detectable vi- rial. Once this envelope is lysed with detergent, the remaining
ral RNA from ACU material. As described previously, ACU capsid can be washed away during the rinse. It is therefore sug-
pieces were inoculated with SARS-CoV-2 and incubated for 24 gested that military personnel wash their uniforms with water,
hours. After the 24-hour incubation period, VTM was added a detergent, and a rinse step as soon as possible after potential
to the falcon tube containing the patch and allowed to be set SARS-CoV-2 exposure. This is especially important for med-
for another 24 hours. Following the 24-hour incubation pe- ics, physicians, physician assistants, and nurses who may have
riod, the inoculated patch was placed in a clean falcon tube, close physical contact with several potential exposures during
40mL of tap water was added to each sample, and they were the day. This practice may serve to reduce the rate of transmis-
vortexed for 20 minutes. The tubes were heated to 65°C and sion and autoinoculation.
70°C for 24 hours. After the 24-hour incubation period, the
uniform pieces were removed from the heated tap water and Disclosure
placed in clean tubes. The tubes were incubated for 24 hours None.
to release the remaining viral particles. After the 24-hour in-
cubation period, initial VTM samples, wastewater samples, Disclaimer
and final VTM elution samples were evaluated by PCR. It was The views expressed herein are those of the author and do not
found that viral RNA was detectable in all three models for reflect the position of The Dwight D. Eisenhower Army Med-
both temperature conditions indicating that a high-tempera- ical Center, the Department of the Army, or the Department
ture wash alone is not sufficient to remove viral RNA from the of Defense.
ACU material (Table 3).
Funding
TABLE 3 A High Temperature Wash Without Detergent Is Not None.
Effective in Removing SARS-CoV-2 Viral RNA From ACU Material
PCR Cycle Threshold References
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ACU = Army Combat Uniform, VTM = viral transport medium, PCR = 5. van Doremalen N, Bushmaker T, Morris DH, et al. Aerosol and
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To our knowledge, this is the first study designed to evaluate 2021;114:163–166.
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Conversely, high temperature without detergent was ineffec- PMID: 37224388; DOI: 10.55460/KR80-X5HF
tive at removing viral RNA from the material. These results
can be explained by reviewing the structure of coronavirus

72 | JSOM Volume 23, Edition 2 / Summer 2023