×

All sources cited at the bottom of this page

 

Most websites you go to for data on COVID-19 will show you a dashboard of “active” cases, the number of people who have been tested and currently have COVID-19. But because of the median 5-day incubation period (the period between exposure to the infection and the appearance of the first symptoms), the number of active cases gives us a rough indication of how many people were infected 5 days ago. Due to this virus spreading so quickly, this number does a poor job of letting us know how many people could potentially be infected right now (and  could be spreading the virus before they show symptoms). This New York Times article explains how Columbia University researchers estimate that there are 11 times more cases than have been reported.

 

The Covid Near Me website aims to give an estimation at how many people are currently infected in your state based on 1) the incubation period and 2) what we know about how quickly the virus spreads. We can use this to project how many confirmed cases we’ll see in 5 days, indicating to us how many people actually have the virus right now.

 

Below are more details about how this estimated active cases value is calculated.

 

From this research paper from March 10th and this research paper from March 17th (from UMass Amherst), we see that the median incubation period is a little over 5 days. Since most hospitals in the US are not testing people who are not showing symptoms, it’s likely that most of the confirmed cases are from people who are past this 5 day period. So to calculate an estimate of active cases today, we will want to take the current active cases number for your state and come up with a projection for 5 days from now.

 

To calculate this number, we can look at how the virus has spread so far in the US. Using the daily active values in the US from this website (all sources cited at the bottom), we can find an exponential trendline that best fits the growth pattern so far

 

From this graph, we can see that the trendline with equation 2.61 * (e^(0.293 * x)) fits the actual growth with an R² of 99%. This isn’t exact, but it can be used to give us a rough indication at how quickly the virus spreads. This will undoubtedly differ drastically from state to state, so the estimated values should only be used as a rough indicator and are by no means confirmed or guaranteed to be accurate.

Sources

Sources for confirmed data (active cases, total cases, total deaths, and total recovered)

Sources for estimated projection

How many people have COVID-19 in your state right now?

*This number is an estimate. It’s calculated by applying the projected exponential spread of the virus in the US to your state, accounting for the median 5 day incubation period. Learn more.

1 in *

people in your state with COVID-19


Confirmed Active The number of people who currently have COVID-19 in your state. This number only represents people who have been tested.

Estimated Active*


Population

Click here for more info about your state (broken down by county).

Total Cases The total number of people who have ever had COVID-19 in your state (including deaths and recovered).

Total Deaths

Total Recovered