Control
Sunlight was adopted
in 1 country.
Dec 9 |
Sunlight reduces COVID-19 risk: real-time meta analysis of 5 studies | |
| Significantly lower risk is seen for mortality, hospitalization, recovery, and cases. 5 studies from 5 independent teams in 4 countries show significant benefit. Meta analysis using the most serious outcome reported shows 37% [22R.. | ||
Jul 22 |
et al., ISPRS International Journal of Geo-Information, doi:10.3390/ijgi14080283 | Spatial and Temporal Correlations of COVID-19 Mortality in Europe with Atmospheric Cloudiness and Solar Radiation |
| Analysis of 37 European countries showing that COVID-19 mortality was significantly negatively correlated with solar radiation in the previous month and positively correlated with cloudiness in both the current month and previous month, a.. | ||
Dec 20 2024 |
et al., Frontiers in Cellular and Infection Microbiology, doi:10.3389/fcimb.2024.1476603 | Longitudinal ozone exposure and SARS-CoV-2 infection in late pregnancy: a retrospective cohort study |
| 40% fewer cases (p=0.23). Retrospective 600 pregnant women in an urban area of China showing a significantly lower risk of SARS-CoV-2 infection in late pregnancy with higher gestational ozone exposure levels. Ozone exposure, driven by photochemical reactions, is s.. | ||
Dec 1 2024 |
, R., PLOS Global Public Health, doi:10.1371/journal.pgph.0004074 (date from preprint) | Early Pandemic Associations of Latitude, Sunshine Duration, and Vitamin D Status with COVID-19 Incidence and Fatalities: A Global Analysis of 187 Countries |
| Analysis of 187 countries showing higher latitude and lower vitamin D levels associated with increased COVID-19 prevalence, mortality, and case fatality rates during the early months of the pandemic. | ||
Nov 29 2024 |
et al., medRxiv, doi:10.1101/2024.11.28.24318154 | Seasonal variation in SARS-CoV-2 transmission in the Netherlands, 2020-2022: statistical evidence for an inverse association with solar radiation and temperature |
| Retrospective ecological time-series study of 109 consecutive weekly SARS-CoV-2 Rt estimates in the Netherlands showing significantly lower transmission with higher solar radiation and temperature, corresponding to a 70-90% higher reprodu.. | ||
Aug 13 2024 |
et al., BMC Public Health, doi:10.1186/s12889-024-19749-3 | Natural and socio-environmental factors in the transmission of COVID-19: a comprehensive analysis of epidemiology and mechanisms |
| Review of natural and socio-environmental factors impacting the transmission of COVID-19. Authors summarized epidemiological and mechanistic evidence showing that high temperature, high humidity, low air pollution levels, and low populati.. | ||
Aug 1 2024 |
et al., Health & Place, doi:10.1016/j.healthplace.2024.103328 | Higher ultraviolet light exposure is associated with lower mortality: An analysis of data from the UK biobank cohort study |
| Non-COVID-19 retrospective analysis of 395,086 UK Biobank participants showing lower all-cause, cardiovascular disease, and cancer mortality associated with higher ultraviolet light exposure, as measured by solarium use and annual average.. | ||
Jul 18 2024 |
et al., Frontiers in Public Health, doi:10.3389/fpubh.2024.1183706 | Associations between meteorological factors and COVID-19: a global scoping review |
| Review of associations between meteorological factors and COVID-19. For sunlight/solar radiation authors found consistent evidence from experimental studies that higher solar radiation negatively affects SARS-CoV-2 viability. Several stud.. | ||
Jun 21 2024 |
et al., PLOS ONE, doi:10.1371/journal.pone.0305323 | Does behavior mediate the effect of weather on SARS-CoV-2 transmission? Evidence from cell-phone data |
| Mediation analysis of meteorological, cell-phone mobility, and building footprint data from five Colorado counties, showing that weather directly impacted COVID-19 hospitalizations, while the indirect effect via changes in time spent indo.. | ||
May 31 2024 |
et al., Heliyon, doi:10.1016/j.heliyon.2024.e31160 | Non-linear effects of meteorological factors on COVID-19: An analysis of 440 counties in the americas |
| Retrospective 440 counties/districts across 7 countries in the Americas, showing solar radiation exhibited an overall negative association with daily new COVID-19 cases. The study used generalized additive models (GAM) and distributed lag.. | ||
Mar 25 2024 |
et al., Tropical Biomedicine, doi:10.47665/tb.41.1.010 | Sunlight exposure might account for the relatively low COVID-19 morbidity and mortality in tropical countries |
| Retrospective analysis of tropical and non-tropical countries showing significantly lower COVID-19 cases and mortality in tropical countries. The study found that specific photovoltaic power output, global horizontal irradiation, diffuse .. | ||
Mar 25 2024 |
et al., Interactive Journal of Medical Research, doi:10.2196/43585 | Influence of the environmental factors and genome diversity on COVID-19 cumulative infection in highland region of China: Comparative correlational study (Preprint) |
| Retrospective 24,826 COVID-19 cases in China showing lower COVID-19 cases with increasing sunlight hours in high altitude regions. Higher sunlight hours was also associated with fewer mutations. | ||
Jun 2 2023 |
et al., Atmosphere, doi:10.3390/atmos14060973 | The Impact of Air Quality and Meteorology on COVID-19 Cases at Kuala Lumpur and Selangor, Malaysia and Prediction Using Machine Learning |
| Analysis of weather data, air quality, and COVID-19 in Malaysia, showing COVID-19 cases negatively correlated with solar radiation and positively correlated with air pollution. | ||
Apr 9 2023 |
et al., medRxiv, doi:10.1101/2023.04.07.23288300 | Association between PM2.5 air pollution, temperature, and sunlight during different infectious stages with the case fatality of COVID-19 in the United Kingdom: a modeling study |
| Modeling of COVID-19 cases in the UK predicting 69% lower mortality for one hour increased sunlight duration. The model predicts lower risk with increased sunlight exposure prior to about 7 days after infection, and increased risk after 7.. | ||
Jan 20 2023 |
et al., International Journal of Environmental Research and Public Health, doi:10.3390/ijerph20031973 | Correlation between UV Index, Temperature and Humidity with Respect to Incidence and Severity of COVID 19 in Spain |
| Analysis of COVID-19 in 5 provinces in Spain, showing UV exposure negatively correlated with COVID-19 cases and hospitalization. | ||
Jan 18 2023 |
et al., medRxiv, doi:10.1101/2023.01.16.23284634 | Prediction of Long COVID Based on Severity of Initial COVID-19 Infection: Differences in predictive feature sets between hospitalized versus non-hospitalized index infections |
| N3C retrospective identifying plant hardiness zone as a predictive variable for long COVID. Authors note that this may be due to sunlight/climate affecting the risk of long COVID, and plan more detailed analysis in future work. | ||
Dec 30 2022 |
, M., The Open COVID Journal, doi:10.2174/26669587-v2-e221209-2022-24 | Higher Scores of Ambient Temperature, Sunshine Hours and UV Index are Associated with Lower COVID-19 Mortality |
| Analysis of COVID-19 deaths in 39 countries, showing mortality negatively correlated with sunshine hours. | ||
Dec 5 2022 |
et al., Journal of Photochemistry and Photobiology B: Biology, doi:10.1016/j.jphotobiol.2022.112619 | Cardiopulmonary and hematological effects of infrared LED photobiomodulation in the treatment of SARS-COV2 |
| 32% shorter hospitalization (p=0.02) and 38% faster recovery (p=0.0006). RCT 30 hospitalized COVID-19 patients investigating the effectiveness of photobiomodulation (PBM) using a vest with near-infrared LEDs (simulating part of the sunlight spectrum). The treatment group showed shorter hospitalization, signifi.. | ||
Nov 24 2022 |
et al., Frontiers in Rehabilitation Sciences, doi:10.3389/fresc.2022.1037649 | Post-COVID-19 complications in home and hospital-based care: A study from Dhaka city, Bangladesh |
| Retrospective 925 COVID-19 patients in Bangladesh reporting that "physical activity and exposure to sunlight was positively associated with earlier recovery from COVID-19 both in home and hospital care". Details are not provided. | ||
Nov 16 2022 |
et al., Scientific Reports, doi:10.1038/s41598-022-24024-9 | Effects of climatic factors on COVID-19 transmission in Ethiopia |
| Analysis of climate and COVID-19 transmission in Ethiopia, showing no association between sunshine duration and COVID-19 risk during the study period. Authors analyze cases only and not outcomes. | ||
Jun 30 2022 |
et al., Journal of Photochemistry and Photobiology, doi:10.1016/j.jpap.2021.100107 | UV and violet light can Neutralize SARS-CoV-2 Infectivity |
| In vitro study showing that UV irradiation is effective for SARS-CoV-2 inhibition at multiple wavelengths including UV-A and violet light. | ||
May 31 2022 |
et al., Experimental Dermatology, doi:10.1111/exd.14617 | Pilot phase results of a prospective, randomized controlled trial of narrowband ultraviolet B phototherapy in hospitalized COVID-19 patients |
| 60% lower mortality (p=0.39), no change in ventilation (p=1), and 25% higher ICU admission (p=1). RCT 30 hospitalized COVID-19 patients showing a non-significant reduction in 28-day mortality with narrowband ultraviolet B (NB-UVB) phototherapy. This double-blind, placebo-controlled trial enrolled high-risk patients aged 50-95 with oxy.. | ||
May 2 2022 |
et al., Journal of Advances in Microbiology Research, 3:1 | The effect of time exposure to sunlight on patients with COVID-19 |
| Survey of 120 COVID-19 cases in Iraq, showing lower risk of severe cases with sunlight exposure. | ||
Apr 26 2022 |
et al., Southern African Journal of Infectious Diseases, doi:10.4102/sajid.v37i1.359 | Vitamin D status and COVID-19 severity |
| 58% fewer symptomatic cases (p=0.004). Prospective study of 100 COVID-19 patients in South Africa, 50 with COVID-19 pneumonia and 50 asymptomatic, showing higher risk of symptomatic COVID-19 with lower exposure to sunlight, and with vitamin D deficiency. Sunlight exposure may .. | ||
Jan 27 2022 |
, R., MedCram | The Case for Sunlight in COVID 19 Patients: Oxidative Stress |
| Review of potential benefits of sunlight for COVID-19 including improved vitamin D levels, the generation and regulation of melatonin, increased enery production in the mitochondria, and reduction in oxidative stress and Reactive Oxygen S.. | ||
Jan 21 2022 |
et al., Nutrients, doi:10.3390/nu14030471 | COVID-19 Mortality in Europe, by Latitude and Obesity Status: A Geo-Spatial Analysis in 40 Countries |
| Ecological study of 40 European countries showing higher COVID-19 incidence and mortality associated with higher latitude (as a proxy for lower sunlight exposure and vitamin D synthesis). The association was stronger for countries with.. | ||
Dec 31 2021 |
et al., Natural Volatiles & Essential Oils, 8:4 | Vitamin D Serum Levels and Its Association With COVID 19 Infection In Babylon Governorate, Iraq |
| 63% fewer cases (p=0.0002). Analysis of 120 COVID-19 and 120 control patients in Iraq, showing lower risk of cases with regular sunlight exposure (3 times/week). | ||
Dec 3 2021 |
et al., The American Journal of Clinical Nutrition, doi:10.1093/ajcn/nqab389 | Associations between predicted vitamin D status, vitamin D intake, and risk of SARS-CoV-2 infection and Coronavirus Disease 2019 severity |
| 23% fewer cases (p=0.0001). Analysis of 39,915 patients with 1,768 COVID+ cases based on surveys in the Nurses' Health Study II, showing higher UVA/UVB exposure associated with lower risk of COVID-19 cases. | ||
Oct 31 2021 |
et al., The Journal of Steroid Biochemistry and Molecular Biology, doi:10.1016/j.jsbmb.2021.105957 | Vitamin D-independent benefits of safe sunlight exposure |
| Review of the benefits of sunlight exposure independent of vitamin D. | ||
Oct 5 2021 |
et al., FEBS Open Bio, doi:10.1002/2211-5463.13309 | Seasonal UV exposure and vitamin D: Association with the dynamics of COVID-19 transmission in Europe |
| Analysis of UV exposure in 26 European countries, showing that cloud-free vitamin D UV dose levels were negatively correlated with COVID-19 prevalence. | ||
Sep 15 2021 |
et al., Communicative & Integrative Biology, doi:10.1080/19420889.2021.1965718 | Infrared light therapy relieves TLR-4 dependent hyper-inflammation of the type induced by COVID-19 |
| In vitro study of human cell cultures showing decreased inflammation and cytokine production with infrared light therapy. Cells were engineered to express components of the TLR4 inflammation pathway implicated in COVID-19 cytokine storms... | ||
Jul 7 2021 |
et al., International Journal of Environmental Research and Public Health, doi:10.3390/ijerph18147266 | Association of Food Intake Quality with Vitamin D in SARS-CoV-2 Positive Patients from Mexico: A Cross-Sectional Study |
| Retrospective 40 COVID+ patients in Mexico, showing vitamin D insufficiency associated with lower sun exposure. | ||
Jun 30 2021 |
et al., Annals of Medicine and Surgery, doi:10.1016/j.amsu.2021.102419 | COVID-19 and sunlight: Impact on SARS-CoV-2 transmissibility, morbidity, and mortality |
| Review of evidence for the benefits of sunlight exposure for COVID-19. | ||
Apr 8 2021 |
et al., British Journal of Dermatology, doi:10.1111/bjd.20093 | Ultraviolet A radiation and COVID-19 deaths in the USA with replication studies in England and Italy |
| 32% lower mortality (p=0.004). Analysis of UVA exposure and COVID-19 mortality in the USA, England, and Italy, showing increased UVA exposure associated with lower mortality. | ||
Feb 28 2021 |
et al., Science of The Total Environment, doi:10.1016/j.scitotenv.2020.143757 | Does solar ultraviolet radiation play a role in COVID-19 infection and deaths? An environmental ecological study in Italy |
| Retrospective COVID-19 cases and solar UV exposure in Italy, showing mortality and cases negatively correlated with solar UV exposure. | ||
Feb 5 2021 |
et al., The Journal of Infectious Diseases, doi:10.1093/infdis/jiab070 | UVB Radiation Alone May Not Explain Sunlight Inactivation of SARS-CoV-2 |
| Experiments have shown that SARS-CoV-2 is inactivated by sunlight much faster than predicted by theory, suggesting that additional mechanisms of inactivation may be involved. Authors note that sensitivity to wavelengths other than UVB mea.. | ||
Jan 31 2021 |
et al., Economics & Human Biology, doi:10.1016/j.ehb.2020.100942 | Sunlight and Protection Against Influenza |
| Retrospective study using CDC data on 12,068 state-weeks showing that increased sunlight exposure is associated with reduced influenza rates during peak fall flu season. A 10% increase in relative sunlight exposure decreases the CDC influ.. | ||
Jan 21 2021 |
, S., Nature, doi:10.1038/s41598-021-81419-w | Autumn COVID-19 surge dates in Europe correlated to latitudes, not to temperature-humidity, pointing to vitamin D as contributing factor |
| Analysis of the increase in COVID-19 cases in European countries, showing no correlation with temperature, but a significant correlation with country latitude. Since UV radiation decreases earlier for higher latitudes, this supports the t.. | ||
Jan 9 2021 |
et al., Environmental Science and Pollution Research, doi:10.1007/s11356-020-12338-y | The effect of weather data on the spread of COVID-19 in Jordan |
| Analysis of COVID-19 and weather data in Jordan, showing solar radiation negatively correlated with COVID-19 cases. | ||
Dec 28 2020 |
et al., Proceedings of the National Academy of Sciences, doi:10.1073/pnas.2012370118 | Global evidence for ultraviolet radiation decreasing COVID-19 growth rates |
| Global analysis of UV radiation and COVID-19 cases, showing that higher UV radiation is associated with a lower daily growth rate of COVID-19 cases. | ||
Nov 30 2020 |
et al., medRxiv, doi:10.1101/2020.11.28.20240242 | On the anti-correlation between COVID-19 infection rate and natural UV light in the UK |
| Analysis of COVID-19 cases in the UK, showing a correlation between increased UV radiation and lower COVID-19 cases. | ||
Nov 2 2020 |
et al., Aerosol Science and Technology, doi:10.1080/02786826.2020.1829536 | The influence of temperature, humidity, and simulated sunlight on the infectivity of SARS-CoV-2 in aerosols |
| Analysis of the effects of temperature, humidity, and simulated sunlight on the decay rate and infectivity of aerosolized SARS-CoV-2 virus particles. The results showed that higher temperature, lower humidity, and higher simulated sunligh.. | ||
Oct 31 2020 |
et al., American Journal of Infection Control, doi:10.1016/j.ajic.2020.07.031 | Susceptibility of SARS-CoV-2 to UV irradiation |
| In vitro study showing high infectious titer SARS-CoV-2 completely inactivated by UVC irradiation in 9 minutes. The UVC dose required for complete inactivation was 1,048 mJ/c. | ||
Oct 19 2020 |
et al., Scientific Reports, doi:10.1038/s41598-020-74825-z | Evidence of protective role of Ultraviolet-B (UVB) radiation in reducing COVID-19 deaths |
| Analysis of 152 countries suggesting that a permanent unit increase in UVI is associated with a 1.2 percentage points decline in daily growth rates of cumulative COVID-19 deaths. | ||
Oct 13 2020 |
et al., Proceedings of the National Academy of Sciences, doi:10.1073/pnas.2008590117 | Seasonality and uncertainty in global COVID-19 growth rates |
| Global analysis of COVID-19 cases and weather, showing increased UV light associated with a lower COVID-19 growth rate. | ||
Sep 28 2020 |
et al., Environmental Science and Pollution Research, doi:10.1007/s11356-020-10930-w | COVID-19 pandemic: environmental and social factors influencing the spread of SARS-CoV-2 in São Paulo, Brazil |
| Analysis of COVID-19 in Brazil, showing a negative correlation between cases and UV radiation. | ||
Aug 31 2020 |
et al., Science of The Total Environment, doi:10.1016/j.scitotenv.2020.139016 | Sunlight exposure increased Covid-19 recovery rates: A study in the central pandemic area of Indonesia |
| Analysis of COVID-19 cases in Indonesia, showing recovery significantly correlated with sunlight exposure. | ||
Jul 23 2020 |
et al., Spatial and Spatio-temporal Epidemiology, doi:10.1016/j.sste.2020.100362 | Covid-19 and vit-d: Disease mortality negatively correlates with sunlight exposure |
| Analysis of COVID-19 mortality and sunlight exposure in continental metropolitan France, showing that average annual sunlight hours were significantly correlated with COVID-19 mortality, with a Pearson coefficient of -0.636. Also see the .. | ||
Jun 26 2020 |
et al., American Journal of Infection Control, doi:10.1016/j.ajic.2020.06.193 | COVID-19 fatalities, latitude, sunlight, and vitamin D |
| Analysis of 88 countries, showing a significant correlation between death rates and latitude, suggesting that sunlight exposure and vitamin D levels influence mortality. | ||
Jun 2 2020 |
et al., Research Square, doi:10.21203/rs.3.rs-32499/v1 | Sunlight and vitamin D in the prevention of coronavirus disease (COVID-19) infection and mortality in the United States |
| Analysis of COVID-19 cases in the USA reporting a potential relationship between latitude and the number of COVID-19 cases (p = 0.08) and deaths (p=0.06). Authors note that sunlight and vitamin D may reduce risk for COVID-19 cases and dea.. | ||
May 20 2020 |
et al., The Journal of Infectious Diseases, doi:10.1093/infdis/jiaa274 | Simulated Sunlight Rapidly Inactivates SARS-CoV-2 on Surfaces |
| In vitro study showing that simulated sunlight rapidly inactivates SARS-CoV-2 on surfaces. | ||
May 19 2020 |
et al., Clinical Infectious Diseases, doi:10.1093/cid/ciaa575 | Higher Solar Irradiance Is Associated With a Lower Incidence of Coronavirus Disease 2019 |
| Analysis of 359 countries and regions showing COVID-19 cases associated with reduced solar irradiance. | ||
Apr 17 2020 |
et al., Science of The Total Environment, doi:10.1016/j.scitotenv.2020.138705 | Investigation of effective climatology parameters on COVID-19 outbreak in Iran |
| Analysis of COVID-19 in Iran, showing cases inversely related to solar radiation, without statistical significance. | ||
Nov 28 2019 |
et al., The Journal of Infectious Diseases, doi:10.1093/infdis/jiz582 | The Influence of Simulated Sunlight on the Inactivation of Influenza Virus in Aerosols |
| Experimental study using a rotating drum chamber exposing influenza virus (H1N1 A/PR/8/34) in aerosols to varied levels of simulated sunlight, showing significantly increased viral decay rates with increasing light intensity. In darkness,.. | ||
Jul 31 2009 |
et al., Dermato-Endocrinology, doi:10.4161/derm.1.4.9063 | The possible roles of solar ultraviolet-B radiation and vitamin D in reducing case-fatality rates from the 1918–1919 influenza pandemic in the United States |
| Analysis of the 1918-1919 influenza pandemic for 12 US states, showing estimated UVB dose correlated with case fatality rates (p = 0.009) and with pneumonia as a complication of influenza (p = 0.005). | ||
May 1 1919 |
, W. Life and Health, May 1919, 34:5 | Sanitarium Treatment of Influenza |
| Retrospective comparison of army hospital vs. sanitarium treatment of influenza, showing lower progression to pneumonia and lower mortality with sanitarium treatment. | ||