Verifying the Theory of Climate Affecting Lethality of COVID-19 by an Analysis in Two Climatic Zones of Chile

Introduction: The study of seasonal influences on the COVID-19 pandemic can take advantage of the unique position of Chile and its different climatic profiles in the north-south extension. The purpose is to verify the influence of seasonal climate changes on the COVID-19 in the temperate and sub-arctic areas of Chile. Methods: We monitored the evolution of CFR in temperate versus sub-boreal regions, reporting from the John Hopkins University COVID-19 Center on the CFR in each province in midwinter, spring, and early summer. Results: CFR worsened from mid-winter to mid-spring in the temperate zone of Chile, while in the sub-boreal area the CFR improves in the same period, (Kruskal Wallis Test, p=0.004). In the temperate zone after the increase in late winter-early spring, CRF tends to stabilize;on the contrary in the sub-boreal zone, there is a more marked tendency to worsen the CFR at the same time (Kruskal Wallis Test, p=0.010). The temperate zone of Chile shows a CFR increasing until spring-like temperate Europe, unlike Europe CFR does not decrease in summer, but the mean minimum temperature in temperate Chile is lower in summer than in temperate Europe. In Patagonian, CFR remains stable or drops from winter to spring but increases in early summer. Conclusion: The temperate and sub-boreal zones of Chile have a markedly different CFR variation profile during the COVID-19 pandemic.

COVID-19 case fatality ratio of Latino America countries with temperate climate partially follows european and oceania trends according to seasonal change

The objective of our study is, therefore, to verify whether the trend of the pandemic regarding the lethality of the virus is similar in Argentina and Chile to that which emerged in the temperate countries of Europe and Oceania. The CFRs were derived from the John Hopkins University database. To check the trend of the Case Fatality Ratio and Argentina, Chile we calculated this index on the same dates in which it was calculated for comparison in European countries and in Australia and New Zealand: i.e., May 6th and from May 6th to the September 21st. We continued comparing the other countries of the southern hemisphere, recalculating the CFR as of 11th November. For comparing a period of year homogeneous, late spring, we calculate the change if CFR from 20th March to 15th April in the North Hemisphere. Our study's results seem to confirm in Latin America a possible influence of the climate and the changing of the seasons in the lethality of the virus. For the same exceptions, it is evident that the study shows that this factor is not the only one nor probably the most important. The obvious exception concerns Argentina, which does not show any summer improvement of the CFR, unfortunately;for this, nation-specific data are not available to verify if the trend is homogeneous in the different climates that the vast territory presents. Other very important factors come into play, among which the diffusivity of the virus also seems to play a role. © 2020 by the authors.