key: cord-0929545-o3pkqwpr authors: Alipio, Mark Marcos title: Do latitude and ozone concentration predict Covid-2019 cases in 34 countries? date: 2020-04-14 journal: nan DOI: 10.1101/2020.04.09.20060202 sha: e468cf4efcd042944b0846620ac1c79ae293af80 doc_id: 929545 cord_uid: o3pkqwpr In this paper, I used multivariate linear regression analysis to determine if latitude and ozone concentration predict Covid-2019 cases in 34 countries worldwide. Data pertaining to Covid-2019 cases were extracted from Worldometer. Ozone concentration levels were taken from the open-access database of World Ozone and Ultraviolet Radiation Data Centre (WOUDC). Latitude of specific area where measurement took place was also provided in the database. Preliminary Kendall rank correlation test revealed that Covid-2019 incidence was positively and significantly related to ozone concentration; however, incidence was not significantly related to latitude. Using multivariate linear regression, a statistically significant link between ozone concentration and Covid-2019 incidence in 34 countries was established; however, I found no statistical association between latitude and Covid-2019 incidence refuting previous claims. Prompt health actions should be developed for areas with high ozone concentration in the present and possibly, future outbreaks; however, extensive laboratory analysis should be conducted to further confirm the findings of the study. Nevertheless, the results of this study could serve as a basis for further clinical and large-scale studies. It has come to my attention that Covid-2019 trajectory could be explained by temperature, humidity, and latitude. 1, 2, 3 However, prediction needs more sound empirical evidence to provide accurate planning strategies for the present and possibly, future outbreaks. Previous works also provided argument pertaining to the possible relationship between latitude dependence of Covid-2019 mortality and Vitamin D deficiency. 4, 5 Vitamin D is strongly affected by ozone variability, since ozone filters Ultraviolet B, an important factor for Vitamin D synthesis. 6 A possible link between ozone concentration and Covid-2019 incidence, therefore, should be established. In this paper, I used multivariate linear regression analysis to determine if latitude and ozone concentration predict Covid-2019 cases in 34 countries worldwide. Data pertaining to Covid-2019 cases were extracted from Worldometer. 7 Ozone concentration levels were taken from the open-access database of World Ozone and Ultraviolet Radiation Data Centre (WOUDC). 8 Ozone concentration was expressed as Dobson unit (DU), the number of molecules of ozone required to generate a 0.01-mm layer of pure ozone at a temperature of 0 ⁰C and a pressure of 1 atm. Unfortunately, data pertaining to ozone concentration were only available in 34 countries. Measurement was recorded by WOUDC on April 2019 and monthly ozone concentration was considered for the analysis. Latitude of specific area where measurement took place was also provided in the database. The complete data of 34 countries were provided in Table 4 . . CC-BY-NC-ND 4.0 International license It is made available under a author/funder, who has granted medRxiv a license to display the preprint in perpetuity. is the (which was not peer-reviewed) The copyright holder for this preprint Mean latitude of countries used in the analysis was 30.9 degrees, mean ozone concentration was 334.2 Dobson units, and mean Covid-2019 case was 277.4 cases ( Table 1) . Kendall rank correlation test revealed that Covid-2019 cases were positively and significantly related to ozone concentration (p<0.001); however, cases were not significantly related to latitude ( Table 2 ). This is indicative that the number of Covid-2019 cases in 34 countries increases with ozone concentration level, while latitude has nothing to do with the burgeoning cases. . CC-BY-NC-ND 4.0 International license It is made available under a author/funder, who has granted medRxiv a license to display the preprint in perpetuity. is the (which was not peer-reviewed) The copyright holder for this preprint Ozone concentration is inversely related to Ultraviolet transmission. 6 While other factors may play an important role in Vitamin D synthesis in the human body, it has been recommended that the most promising means of mitigating the burden of Vitamin D deficiency seems to be by increased Ultraviolet exposure (at optimal level). 6 This study noted several limitations. The sample size is small; hence, generalizability of the results is limited to the countries included in the analysis. Also, actual patients' information were not used to support the claim on the relationship between Vitamin D supplementation and Covid-2019 clinical outcome. Therefore, clinical trials and large sample studies should be conducted to further verify the causal link among these variables. . CC-BY-NC-ND 4.0 International license It is made available under a author/funder, who has granted medRxiv a license to display the preprint in perpetuity. is the (which was not peer-reviewed) The copyright holder for this preprint . https://doi.org/10.1101/2020.04.09.20060202 doi: medRxiv preprint In conclusion, a statistically significant link between ozone concentration and Covid-2019 cases in 34 countries was established in the study; however, I found no statistical association between latitude and The author declares no conflict of interest. None. No funding to declare. . CC-BY-NC-ND 4.0 International license It is made available under a author/funder, who has granted medRxiv a license to display the preprint in perpetuity. is the (which was not peer-reviewed) The copyright holder for this preprint . https://doi.org/10.1101/2020.04.09.20060202 doi: medRxiv preprint . CC-BY-NC-ND 4.0 International license It is made available under a author/funder, who has granted medRxiv a license to display the preprint in perpetuity. is the (which was not peer-reviewed) The copyright holder for this preprint . https://doi.org/10.1101/2020.04.09.20060202 doi: medRxiv preprint Transmission of SARS and MERS coronaviruses and influenza virus in healthcare settings: the possible role of dry surface contamination The effects of temperature and relative humidity on the viability of the SARS coronavirus Temperature and latitude analysis to predict potential spread and seasonality for COVID-19. Available at SSRN 3550308 Latitude Dependence of the COVID-19 Mortality Rate-A Possible Relationship to Vitamin D Deficiency? Vitamin D Supplementation Could Possibly Improve Clinical Outcomes of Patients Infected with Coronavirus-2019 (COVID-2019) Vitamin D Synthesis by UV Radiation: the Importance of Ozone Monitoring COVID-19 Coronavirus Pandemic Self-care for common colds: the pivotal role of vitamin D, vitamin C, zinc, and Echinacea in three main immune interactive clusters (physical barriers, innate and adaptive immunity) involved during an episode of common colds-Practical advice on dosages and on the time to take these nutrients/botanicals in order to prevent or treat common colds Evidence that Vitamin D Supplementation Could Reduce Risk of Influenza and COVID-19 Infections and Deaths