The Influence of Simulated Sunlight on the Inactivation of Influenza Virus in Aerosols
The Journal of Infectious Diseases, DOI: 10.1093/infdis/jiz582
Michael Schuit, Sierra Gardner, Stewart Wood, Kristin Bower, Greg Williams, Denise Freeburger, and Paul Dabisch
National Biodefense Analysis and Countermeasures Center, Operated by BNBI for the US Department of Homeland Security Science and Technology Directorate, Frederick, MD, USA
UV-C air purifiers have been in use in some homes, hospitals, and businesses for decades
Room-sized UV-C purifiers cost as little as $40
Air purifiers for an entire home cost <$150 (to be installed in existing heating system)
- Make your own UVB Vitamin D lamp for 40 dollars - Jan 2019
- Note UV-C is better than UV-B which is better than sunlight at killing viruses
- Some people compromise by having UVB which generates Vitamin D in skin and kill virus somewhat
- Make your own UVB Vitamin D lamp for 40 dollars - Jan 2019
- More UV and vitamin D, less infectious disease – Jan 2017
900: Items in both categories Virus and UV:
- More UVB, less Coronavirus – including SARS-CoV-2 – Aug 2020
- Less COVID-19 at high altitude due to more Vitamin D or other possible reasons – July 2020
- Far fewer COVID-19 deaths in the summer (Europe, Canada)
- High-altitude Cusco, Peru has far lower rate of COVID-19 than others (high UVB and Vitamin D) - June 2020
- Influenza Virus aerosols killed by 10 minutes of sunlight (far faster if use UV-C) – Nov 2019
- Influenza Virus aerosols killed by 10 minutes of sunlight (faster if use UVB, UVCC– Nov 2019
- Ultraviolet light kills cold and flu viruses, and generates Vitamin D in the skin
Note: All coronaviruses have envelopes, Influenza is an enveloped virus which lacks a crown
Download the PDF from Vitamin D Life
Background. Environmental parameters, including sunlight levels, are known to affect the survival of many microorganisms in aerosols. However, the impact of sunlight on the survival of influenza virus in aerosols has not been previously quantified.
Methods. The present study examined the influence of simulated sunlight on the survival of influenza virus in aerosols at both 20% and 70% relative humidity using an environmentally controlled rotating drum aerosol chamber.
Results. Measured decay rates were dependent on the level of simulated sunlight, but they were not significantly different between the 2 relative humidity levels tested. In darkness, the average decay constant was 0.02 ± 0.06 min-\ equivalent to a half-life of 31.6 minutes. However, at full intensity simulated sunlight, the mean decay constant was 0.29 ± 0.09 min-、equivalent to a half-life of approximately 2.4 minutes.
Conclusions. Short-range aerosol transmission of the virus may be possible in full intensity sunlight, but the virus would be unlikely to survive in an infectious state over long distances. These results are consistent with epidemiological findings that sunlight levels are inversely correlated with influenza transmission, and they can be used to better understand the potential for the virus to spread under varied environmental conditions.