Oct 7 |
Sunlight for COVID-19: real-time meta analysis of 5 studies | |
Statistically significant lower risk is seen for mortality, hospitalization, recovery, and cases. 5 studies from 5 independent teams in 4 countries show significant improvements. Meta analysis using the most serious outcome reported shows.. | ||
Aug 13 |
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.. | ||
Jul 18 |
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 |
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 |
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 |
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 |
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 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.. | ||
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. |
Please send us corrections, updates, or comments.
c19early involves the extraction of 100,000+ datapoints from
thousands of papers. Community updates
help ensure high accuracy.
Treatments and other interventions are complementary.
All practical, effective, and safe
means should be used based on risk/benefit analysis.
No treatment or intervention is 100% available and effective for all current
and future variants.
We do not provide medical advice. Before taking any medication,
consult a qualified physician who can provide personalized advice and details
of risks and benefits based on your medical history and situation. FLCCC and WCH
provide treatment protocols.
Thanks for your feedback! Please search before submitting papers and note
that studies are listed under the date they were first available, which may be
the date of an earlier preprint.