Top 10 Disinfectants for COVID-19

Jarod M. Hanson, DVM, PhD, DACVPM, DABT, University of Maryland

ArticleApril 20204 min read
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Published April 3, 2020, at 6:49 AM CST. Updated April 7, 2020, at 7:51 AM CST.

SARS-CoV-2 is an enveloped RNA virus. The relative fragility of the lipid membranes in the viral envelope renders it susceptible to most soaps, disinfectants, drying, and UV light.

Cleaning and disinfection should focus on those surfaces most likely to be contaminated, including common contact surfaces and items such as door knobs, computers and keyboards, stethoscopes, otoscopes, ophthalmoscopes, thermometers, pleximeters, drawer pulls, refrigerator handles, and restrooms. Examination room tables and floors should be routinely disinfected, and immediately after any use by staff or clients.

Regardless of the disinfectant used, cleaning and disinfecting involve the following steps:

  1. Removal of visible organic matter from the surface,

  2. Cleaning with an appropriate detergent and drying time, and

  3. Application of disinfectant (following the manufacturer’s directions regarding appropriate dilution, application method, contact time, expiration after mixing, and storage conditions).

Different disinfectant types should never be mixed. Selection should be based on surface type and conditions including temperature, as some disinfectants require increased contact time at lower ambient temperatures. As disinfectant supplies are strained during the COVID-19 pandemic, availability may vary, and having alternate options is key.

The following active ingredients can be used as the basis of an effective disinfection routine for SARS-CoV-2:

1. Detergents

Although detergents are not disinfectants, prepublication research showed that soap (which contains detergents) at 1:49 dilution kills SARS-CoV-2 in 15 minutes or less.1 This is extremely important, given the general shortage of disinfectants at this time, and reinforces the benefits of hand-washing beyond gross removal of contaminants. If available, it is still highly recommended to apply a true disinfectant after cleaning with soap to enhance the killing of any remaining microorganisms.

2. Bleach/sodium hypochlorite

Household bleach applied at 1:49 or 1:99 dilutions killed SARS-CoV-2 in 5 minutes.1 Bleach can damage many surfaces and should be used with caution.

3. Accelerated hydrogen peroxide

The product label indicates it is virucidal for common viruses including canine coronavirus and influenza when diluted 1:64 and applied for a contact time of 5 minutes on solid, non-porous surfaces.2

4. Potassium peroxymonosulfate

Potassium peroxymonosulfate should be used as a 1% solution (1:100 dilution) and applied for a contact time of 10 minutes.3

5. Ethanol, 60% or greater

Ethanol at 70% was demonstrated to kill SARS-CoV-2 in 5 minutes or less. Ethanol at 60% is the lowest recommended concentration for use against SARS-CoV-2, and is expected to have a kill time similar to 70% ethanol.7

6. Chlorhexidine, 0.05%

SARS-CoV-2 was undetectable after 5 minutes of contact time.1

7. Isopropyl alcohol, 70%

Solutions of 70% isopropyl alcohol have demonstrated efficacy against multiple viruses. Suggested contact time varies from 1-3 minutes, or until dry. Alcohol wipes are commonly recommended for surfaces that could be damaged by bleach (eg, phones, computer keyboards).

8. Hydrogen peroxide, 3%

Hydrogen peroxide at 3% killed rhinovirus in 6-8 minutes. Because rhinovirus is not enveloped and inherently much more resistant to disinfectants than SARS-CoV-2, this suggests 3% hydrogen peroxide should also kill SARS-CoV-2.5

9. Povidone-iodine, 7.5%

Povidone-iodine at 7.5% killed SARS-CoV-2 virus in 5 minutes or less of contact time.1

The U.S. Environmental Protection Agency maintains a list of disinfectants believed to be effective against SARS-CoV-2; this list is based on existing label claims to kill other viruses believed to be equal to or more resistant than SARS-CoV-2 to disinfection.

10. Quaternary ammonium compounds, acids & phenolic products

Other options to consider include quaternary ammonium compounds, acids (eg, citric, L-lactic, glycolic), and phenolic products. Formulations vary substantially for all of these products, with many occurring as mixtures with other disinfectants, predominantly alcohols. Manufacturer's directions regarding contact time and dilution should be followed. If SARS-CoV-2 or another coronavirus is not specifically listed, products labeled to kill emerging viral pathogens and/or influenza A should be selected.

Ethanol less than 60% (120 proof), methanol, distilled white vinegar, and tea tree oil should be avoided; these have a demonstrated lack of, or unknown, efficacy against SARS-CoV-2.5,6

Thymol, an oil extracted from thyme, is found in some natural disinfectant products. The ASPCA considers thymol to be nontoxic to dogs and cats, but the labels of any thymol products should be reviewed before use to ensure the product does not contain other essential oils that could be toxic, especially to cats.8