Pulsed-Xenon Ultraviolet Light Highly Inactivates Human Coronaviruses on Solid Surfaces, Particularly SARS-CoV-2

Area of Science:

• Microbiology
• Infectious Diseases
• Public Health

Background:

• Non-pharmaceutical interventions are crucial for managing viral pandemics and preventing the emergence of new variants.
• Efficient disinfection methods are essential in healthcare settings to control the spread of human coronaviruses (CoVs).

Purpose of the Study:

• To evaluate the efficacy of pulsed-xenon ultraviolet (PX-UV) light in disinfecting surfaces contaminated with three different human coronaviruses (HCoV-229E, MERS-CoV, and SARS-CoV-2).
• To compare the effectiveness of PX-UV light with conventional low-pressure mercury UVC lamps for SARS-CoV-2 inactivation.

Main Methods:

• Testing the disinfection capabilities of a characterized PX-UV light source on dried human coronaviruses on surfaces.
• Comparing PX-UV inactivation of SARS-CoV-2 with UVC inactivation using equivalent irradiances.

Main Results:

• PX-UV light completely inactivated all tested CoVs on solid surfaces, reducing infectivity by up to 4 orders of magnitude.
• A cumulative dose of 21.162 mJ/cm² (5.402 mJ/cm² UVC) with PX-UV light achieved complete inactivation.
• PX-UV light demonstrated superior inactivation of SARS-CoV-2 compared to continuous UVC irradiation at equivalent irradiances.

Conclusions:

• PX-UV light is a highly effective and rapid method for disinfecting surfaces contaminated with human coronaviruses.
• PX-UV technology shows significant potential as a decontamination strategy against current and future CoV outbreaks in healthcare environments.