Through up-to-date visuals, track how testing volume, positivity, and proportion give a sense of whether the occurrence of new cases is slowing or growing.
|District of Columbia||2.6%||2.2%||0.4%|
This page was last updated on Thursday, December 3, 2020 at 08:15 AM EST.
This graph answers two questions for each state:
The states are ordered by average percentage of positive tests for this week, but growth in the green bar is an important indicator that a state is moving in the right direction.
This initiative relies upon publicly available data from multiple sources. States are not consistent in how and when they release and update their data, and some may even retroactively change the numbers they report. This can affect the percentages you see presented in these data visualizations. We are taking steps to account for these irregularities in how we present the information, but it is important to understand the full context behind these data.
Weekly averages are calculated using weeks that run from Monday to Sunday.
Testing data from The COVID Tracking Project;
cases data from JHU CSSE;
and population from ACS 1-year data (2018).;
It is important to track the testing that states are doing to diagnose people with COVID-19 infection in order to gauge the spread of COVID-19 in the U.S. and to know whether enough testing is occurring. When states report the number of COVID-19 tests performed, this should include the number of viral tests performed and the number of patients for which these tests were performed. Currently, states may not be distinguishing overall tests administered from the number of individuals who have been tested. This is an important limitation to the data that is available to track testing in the U.S., and states should work to address it.
When states report testing numbers for COVID-19 infection, they should not include serology or antibody tests. Antibody tests are not used to diagnose active COVID-19 infection and they do not provide insights into the number of cases of COVID-19 diagnosed or whether viral testing is sufficient to find infections that are occurring within each state. States that include serology tests within their overall COVID-19 testing numbers are misrepresenting their testing capacity and the extent to which they are working to identify COVID-19 infections within their communities. States that wish to track the number of serology tests being performed should report those numbers separately from viral tests performed to diagnose COVID-19.
Our data provider, The Covid Tracking Project, is in the process of changing how it maps states’ data to the categories we use for our positivity calculations. These changes mean the category of data we use in our denominator (Total tests) may now include tests previously not included in our calculations, which in turn may result in a test positivity calculation that is lower than what we would have calculated for the state prior to the change.
With this significant change, we will once again review our data inputs and calculations to ensure that our numbers reflect the most responsible public health calculation of test positivity.