Disinfectant efficacy on Covid-19 mutations (emerging genetic variants of concern) – Delta variant update

Jul 12, 2021

Technical Bulletin

Executive Summary
All Callington Group disinfectant products have excellent efficacy against Covid-19 virus. This has been proven by testing against related approved surrogate viruses such as murine hepatitis virus and influenza virus.

These results remain valid for all mutated Covid-19 virus strains (Emerging Genetic Variants Of Concern) identified. Callington Group disinfectants can be used to rapidly and effectively disinfect all surfaces where Covid-19 is either suspected or known, regardless of the variant present. This advice is consistent with current advice from both the US EPA¹, the Australian TGA² ,the US CDC³, and the European CDC⁴.

Background

The Covid-19 pandemic is continuing to spread throughout the globe. In the 18 months since it has been formally identified, health authorities have detected many emerging genetic variants of the virus, leading to increased transmission and morbidity in some cases. For example, in December 2020, a new mutant of SARS-CoV-2 was detected in the UK which is suspected to be substantially more infectious. At the same time, another strain was detected in South Africa, also with a distinct infectivity profile. More recently a new viral lineage was reported in Brazil.

The most recent mutation is the so-called “Delta” variant (lineage B.1.617.2), which was first detected in India in late 2020 and in other countries in late February 2021. Since then it has become the dominant Variation Of Concern throughout most countries, due to its’ higher tranmissibility.

A short summary by the World Health Organisation of the current Variants Of Concern⁵ are as follows:

Scope and Regulatory Framework
This bulletin applies to all Callington Group disinfectants. No advice or guidance can be inferred or given for non-Callington approved disinfectants.

Explanation
The ability of a disinfectant to kill covid-19 virus is related to the chemical make-up of both the virus and the disinfectant. Disinfectants work by chemically inactivating viruses. The difficulty of killing a virus depends on its physical features, and the recent mutations to SARS-CoV-2 have not changed the basic physical properties. The lipid envelope that surrounds the Covid-19 virus and all other enveloped viruses is easily attacked by the disinfectant and this occurs regardless of the morphology (structure) of the proteins on the surface of the viruses. This means that the Emerging Covid-19 strains with variations in their surface structure do not have any additional protection against chemical attack. The general mode of action of how a disinfectant attacks an enveloped virus is shown here:

a) Disinfectant attaches the virus via strong adsorption to the lipid envelope surface.
b) Disorganization and severe damage of lipid envelope occurs due to the interaction between the disinfectant and viral particles.
c) This results in the leakage of the viral genome and consequent deactivation of the virus.

Recommendations
You can continue to recommend with full confidence all Callington Group disinfectants for use against all Covid-19 Emerging Genetic Variants Of Concern.

Written by,
Dr. Paul Wynn-Hatton
Group Technical Director
Callington Haven Pty Ltd
+61 2 9898 2753
pwh@callington.com

References:

1. https://www.epa.gov/coronavirus/do-disinfectants-kill-newer-strains-coronavirus
2. https://www.tga.gov.au/surrogate-viruses-use-disinfectant-efficacy-tests-justify-claims-against-covid-19
3. https://www.cdc.gov/coronavirus/2019-ncov/transmission/variant.html
4. https://www.ecdc.europa.eu/sites/default/files/documents/Infection-prevention-and-control-in-healthcare-settings-COVID-19_6th_update_9_Feb_2021.pdf
5. https://www.who.int/en/activities/tracking-SARS-CoV-2-variants/