Note: This dashboard contains the results of a predictive model. The author has tried to make it as accurate as possible. But the COVID-19 situation is changing quickly, and these models inevitably include some level of speculation.

## Estimated Infected Population By Country

with respect to days since outbreak

Tip: Click (Shift+ for multiple) on countries in the legend to filter the visualization.

Latest Country Estimates

Date Estimated Infected Lower Bound Estimates Upper Bound Estimates
Country
Brazil 2020-04-04 31,390 24,146 44,843
China 2020-04-04 83,073 82,543 118,676
France 2020-04-04 251,153 193,195 358,790
Germany 2020-04-04 168,627 129,713 240,895
Iran 2020-04-04 86,020 66,170 122,886
Italy 2020-04-04 171,848 132,191 245,497
Japan 2020-04-04 7,697 5,920 10,995
Portugal 2020-04-04 20,452 15,732 29,216
Singapore 2020-04-04 1,931 1,485 2,759
South Korea 2020-04-04 10,935 10,156 15,621
Spain 2020-04-04 214,388 164,914 306,269
United Kingdom 2020-04-04 111,142 85,494 158,775
United States 2020-04-04 786,124 604,711 1,123,034

## Infected vs. number of confirmed cases

Allows you to compare how countries have been tracking the true number of infected people. The smaller deviation from the dashed line (45 degree line) the better job at tracking the true number of infected people.

Tip: Click (Shift+ for multiple) on countries in the legend to filter the visualization.

Latest Observed vs. Estimate of Infected Cases

Date Observed Cases Estimated Infected
Country
Brazil 2020-04-04 10,360 31,390
China 2020-04-04 82,543 83,073
France 2020-04-04 90,848 251,153
Germany 2020-04-04 96,092 168,627
Iran 2020-04-04 55,743 86,020
Italy 2020-04-04 124,632 171,848
Japan 2020-04-04 3,139 7,697
Portugal 2020-04-04 10,524 20,452
Singapore 2020-04-04 1,189 1,931
South Korea 2020-04-04 10,156 10,935
Spain 2020-04-04 126,168 214,388
United Kingdom 2020-04-04 42,477 111,142
United States 2020-04-04 308,850 786,124

## Methodology

We argue that the number of infected in the past can be inferred using today's number of deaths and average fatality rate from confirmed cases in the following way:

$$I_{t-j} = \frac{D_t}{{CFR}_t}$$

where $I_t$ = number of infected, $D_t$ = number of deaths, and ${CFR}_t$ = case fatality rate = $\frac{D}{C}$. The $j$ depends on the average number of days that covid patients die after having the first symptoms.

Assumption 1: The case fatality rate is a good proxy for the fatality rate of the infected population

Then, in order to estimate the current number of infected $I_t$ we need to estimate its growth rate from $t-j$ to $t$.

$$I_t = (1+\hat{g})^j I_{t-j}$$

Assumption 2: The growth rate of infected $\hat{g}$ is an unbiased estimate of $g$ .

For now we estimate $g$ using the average growth rate since having the first infected person.

Assumption 3: It takes on average 8 days to die after having the first symptoms.

This analysis was conducted by Joao B. Duarte. Relevant sources are listed below: