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Background Non-therapeutic interventions such as practicing good hand hygiene continue to be the mainstay of protection from SARS-CoV-2 and other emerging respiratory viruses. Methods We have evaluated a range of commercially available personal care products including soaps, handwash liquids and alcohol-based hand sanitizers for antiviral efficacy against a clinical isolate of SARS-CoV-2 using internationally accepted standardized protocols at user-relevant contact time-points and product dilutions. Results All the tested products resulted in 3 to 4 log reduction of SARS-CoV-2 titer. Conclusion Our data re-affirms recommendations by global public health authorities that proper hand hygiene can reduce SARS-CoV-2 viral load significantly which should likely limit spread of the contagion.

Objectives: Early in the COVID-19 pandemic, global health authorities identified and emphasized the importance of practicing proper hand hygiene to reduce the transmission of SARS-CoV-2 and to diminish the chances of becoming infected. It is well established in the scientific literature that surfactants and alcohols are capable of inactivating enveloped viruses such as SARS-CoV-2. However, given the novel nature of the virus, Unilever adopted an evidence-based approach to demonstrate virucidal efficacy of marketed bar soaps, liquid handwashes, and alcohol-based hand sanitizers against the original and selected variants of SARS-CoV-2. Methods: High titers of clinically isolated and laboratory-propagated SARS-CoV-2 strains were subjected to a range of selected proprietary formulations from Unilever at end-user–relevant dilutions, temperature, and contact duration, and were tested according to the internationally recognized ASTM E-1052 test protocol. Results: All tested personal-care formulations were effective against the parental SARS-CoV-2 strain as well as the β (beta) and δ (delta) variants of concern. More specifically, bar soaps with a varying concentration of total fatty matter content and liquid handwashes with varying levels of total surfactants reduced the viral titer by >99.9% within 20 seconds. Alcohol-based hand sanitizers demonstrated >99.99% reduction of input viral load within 15 seconds of contact with the viral inoculum. Conclusions: In conclusion, we have provided empirical proof that well-designed personal-care formulations that act through generic physicochemical mechanism against the basic structure of the virus particle have high virucidal efficacy against the original and evolved SARS-CoV-2 variants. Furthermore, we argue that due to the broad-spectrum mode of action of these tested formulations, the continued practice of good hand hygiene practices with everyday products holds significant promise as an easily accessible, economic, and effective nontherapeutic public health intervention toward reducing the transmission of present and future variants of SARS-CoV-2 across communities and populations.

The second and third waves of COVID-19 pandemic have largely been driven by the surge of successive SARS-CoV-2 variants of concern (VOC). These VOC have rapidly spread through multiple geographies being enabled by high transmission rates and/or high viral load compared to the original parent strain. Consequently, the altered phenotypes of these VOC have posed greater challenges to diagnostic and clinical management of COVID-19. Despite considerable progress being made on vaccine roll out, practicing proper hand hygiene has been advocated as a consistent precautionary intervention as more virulent VOC continue to emerge and spread across geographies.Two variants of concern, namely beta and delta, have recently been shown to escape antibody-mediated neutralization by virtue of acquired mutations in the receptor-binding domain of the viral spike protein which binds to the human ACE2 receptor for cellular entry. In this report we have empirically determined the efficacy of a range of personal care formulations in inactivating the beta and delta variants of SARS-CoV-2. High titres of these variants were exposed to marketed personal care formulations from Unilever under standard in-vitro suspension test-based conditions relevant to end-user habits. All the formulations demonstrated greater than 99.9% reduction in viral infective titres. The rate of inactivation by these products were comparable to that of the original strain of SARS-CoV-2 virus tested under the same conditions. Therefore, it can be concluded that well-designed personal care formulations when tested under consumer-centric conditions, and with proven efficacy against the parent strain of SARS-CoV-2 will continue to be effective against extant and emerging variants of SARS-CoV-2. This is through their broad-spectrum mode of action (disruption of lipid bilayer of the host-derived viral envelope, denaturation of envelop and nucleocapsid proteins, and disruption of genome) which is independent of the escape mutations that facilitate immune evasion or enhanced transmissibility.