Table 1. First regression: Rate of rise of confirmed cases of COVID-19 in 50 countries, and the associated local meteorological and demographic variables.
| Country | CT Conf Cases | CT-1 Conf Cases | R2 | Tmin Median | DP Median | Land Area Per Capita | Median age | Conf Cases Days |
|---|---|---|---|---|---|---|---|---|
| Algeria | 0.081 | 12.42 | 0.969 | 56.3 | 25.2 | 0.05431 | 28.9 | 42.0 |
| Armenia | 0.103 | 9.74 | 0.909 | 26.6 | 25.2 | 0.00961 | 36.6 | 37.0 |
| Austria | 0.097 | 10.26 | 0.941 | 29.1 | 31.2 | 0.00915 | 44.5 | 42.0 |
| Belgium | 0.090 | 11.17 | 0.913 | 38.7 | 37.4 | 0.00261 | 41.6 | 63.0 |
| Bosnia and Herzegovina | 0.086 | 11.68 | 0.967 | 20.3 | 23.8 | 0.01554 | 43.3 | 33.0 |
| Croatia | 0.074 | 13.59 | 0.977 | 32.9 | 32.8 | 0.01363 | 43.9 | 42.0 |
| Czechia | 0.091 | 10.93 | 0.942 | 33.0 | 30.2 | 0.00721 | 43.3 | 37.0 |
| Egypt | 0.076 | 13.21 | 0.928 | 48.3 | 38.7 | 0.00973 | 24.1 | 53.0 |
| Estonia | 0.088 | 11.36 | 0.908 | 31.5 | 32.5 | 0.03196 | 43.7 | 40.0 |
| Finland | 0.062 | 16.13 | 0.899 | 19.3 | 22.3 | 0.05485 | 42.8 | 69.0 |
| France | 0.071 | 14.03 | 0.940 | 34.6 | 38.2 | 0.00839 | 41.7 | 74.0 |
| Germany | 0.074 | 13.49 | 0.940 | 34.7 | 33.4 | 0.00416 | 47.8 | 71.0 |
| Greece | 0.074 | 13.52 | 0.904 | 40.1 | 42.2 | 0.01237 | 45.3 | 41.0 |
| Hungary | 0.081 | 12.29 | 0.965 | 32.0 | 31.3 | 0.00937 | 43.6 | 34.0 |
| Iceland | 0.072 | 13.81 | 0.881 | 15.5 | 17.4 | 0.29378 | 37.1 | 39.0 |
| India | 0.055 | 18.32 | 0.903 | 64.0 | 56.6 | 0.00215 | 28.7 | 68.0 |
| Iran | 0.076 | 13.18 | 0.820 | 34.8 | 18.5 | 0.01939 | 31.7 | 48.0 |
| Iraq | 0.058 | 17.13 | 0.913 | 49.3 | 45.5 | 0.01080 | 21.2 | 43.0 |
| Ireland | 0.104 | 9.66 | 0.947 | 35.8 | 37.4 | 0.01395 | 37.8 | 38.0 |
| Israel | 0.096 | 10.45 | 0.986 | 46.0 | 42.3 | 0.00250 | 30.4 | 46.0 |
| Japan | 0.041 | 24.67 | 0.967 | 44.6 | 38.2 | 0.00288 | 48.6 | 76.0 |
| Kuwait | 0.035 | 28.56 | 0.792 | 56.9 | 46.9 | 0.00417 | 43.2 | 43.0 |
| Lebanon | 0.067 | 15.02 | 0.929 | 41.8 | 40.4 | 0.00150 | 29.7 | 46.0 |
| Malaysia | 0.044 | 22.77 | 0.932 | 74.8 | 75.8 | 0.01015 | 33.7 | 73.0 |
| Mexico | 0.089 | 11.23 | 0.967 | 46.4 | 36.7 | 0.01508 | 29.2 | 39.0 |
| Moldova | 0.098 | 10.23 | 0.947 | 31.6 | 29.3 | 0.00814 | 29.3 | 30.0 |
| Morocco | 0.098 | 10.19 | 0.974 | 44.2 | 18.5 | 0.01209 | 37.7 | 36.0 |
| Netherlands | 0.097 | 10.34 | 0.894 | 36.8 | 37.5 | 0.00197 | 29.1 | 40.0 |
| Norway | 0.080 | 12.50 | 0.840 | 21.1 | 21.5 | 0.06738 | 42.8 | 41.0 |
| Oman | 0.049 | 20.28 | 0.972 | 57.9 | 52.9 | 0.06061 | 39.5 | 43.0 |
| Pakistan | 0.095 | 10.51 | 0.952 | 49.6 | 36.5 | 0.00349 | 26.2 | 41.0 |
| Philippines | 0.055 | 18.09 | 0.863 | 74.2 | 76.1 | 0.00272 | 30.1 | 68.0 |
| Poland | 0.102 | 9.80 | 0.923 | 31.1 | 30.9 | 0.00809 | 24.1 | 34.0 |
| Portugal | 0.109 | 9.16 | 0.957 | 47.9 | 48.6 | 0.00898 | 41.9 | 36.0 |
| Qatar | 0.056 | 17.82 | 0.798 | 57.9 | 49.5 | 0.00403 | 33.7 | 38.0 |
| Romania | 0.095 | 10.50 | 0.977 | 28.4 | 30.3 | 0.01196 | 44.6 | 41.0 |
| Saudi Arabia | 0.098 | 10.22 | 0.927 | 59.0 | 29.0 | 0.06175 | 42.5 | 36.0 |
| Serbia | 0.105 | 9.53 | 0.916 | 34.2 | 32.9 | 0.01001 | 30.8 | 32.0 |
| Singapore | 0.031 | 32.04 | 0.932 | 77.4 | 74.7 | 0.00012 | 43.4 | 75.0 |
| Slovakia | 0.079 | 12.65 | 0.841 | 26.5 | 27.4 | 0.00881 | 35.6 | 32.0 |
| Slovenia | 0.067 | 14.83 | 0.803 | 32.3 | 33.3 | 0.00969 | 44.9 | 33.0 |
| South Korea | 0.058 | 17.10 | 0.882 | 29.4 | 23.6 | 0.00190 | 44.9 | 76.0 |
| Spain | 0.100 | 10.01 | 0.949 | 42.2 | 43.0 | 0.01067 | 43.9 | 66.0 |
| Sweden | 0.076 | 13.14 | 0.915 | 18.9 | 22.8 | 0.04063 | 41.1 | 67.0 |
| Switzerland | 0.096 | 10.43 | 0.899 | 30.7 | 33.6 | 0.00457 | 42.7 | 42.0 |
| Thailand | 0.032 | 31.33 | 0.869 | 73.4 | 71.3 | 0.00732 | 39.0 | 76.0 |
| Turkey | 0.177 | 5.65 | 0.924 | 27.4 | 31.1 | 0.00913 | 32.2 | 27.0 |
| United Arab Emirates | 0.039 | 25.87 | 0.950 | 64.8 | 56.9 | 0.00845 | 38.4 | 69.0 |
| United Kingdom | 0.075 | 13.33 | 0.964 | 36.1 | 36.3 | 0.00356 | 40.6 | 67.0 |
| Vietnam | 0.027 | 36.94 | 0.924 | 73.2 | 71.4 | 0.00319 | 31.9 | 75.0 |
Fifty representative countries meeting specific criteria (e.g. all Northern Hemisphere, because seasons in Southern Hemisphere are opposite) are shown. Meteorological data (daily minimum and average temperatures, daily dewpoint) were obtained from NOAA stations closest to the latitude and longitude listed in the JHU COVID-19 database (https://github.com/CSSEGISandData/COVID-19) as the location from which cases in each country were associated. Median minimum temperature (Tmin MEDIAN) and dewpoint (DP MEDIAN) were ascertained for each country over the timeframe that cases were increasing between 1/22/20 (when data began to be collected) and 4/6/20. Median average temperature is included as a reference to provide the reader with additional climate information about each country. Linear regression of the log of the daily cumulative COVID-19 confirmed cases versus time (sequential days) was conducted, starting with the date of the first case for each country, and the resulting regression coefficients (which were termed coefficients of time (CT)) for each country was thereby obtained. R2 are shown for this linear regression in each country. The reciprocal of CT (CT-1) was used in a second regression analysis of CT-1 vs Tmin MEDIAN, to explore the correlation between temperature and rates of increase in the log of confirmed cases. The second regression included with temperature or dewpoint the additional independent variables of Land Area per capita, Median Age, and Days of Cases for each country, because of the potential influence of these variables on interactions and behavior that could influence rates of transmission. Land area for each country was obtained from Worldometer (https://www.worldometers.info/coronavirus/#countries) and median age from CIA World Factbook (https://www.cia.gov/library/publications/the-world-factbook/fields/343rank.html).